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HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
19 Feb 2014 02:09 - 19 Feb 2014 02:15 #220550
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-12 ft snow Feb6-21,2014!
Update #11: 300 hours after initial post, 2-10 ft of snow has already fallen in southwest BC, Washington, Oregon, and California,
including 2-4 ft in the past 48 hours, with an additional 2-4 ft predicted the rest of this week for WA, OR, and southwest BC!
The climax of this storm cycle has been going off in the Pacific Northwest the past 2 days, the most intense period of snowfall thus far in the 2013-14 season! The heavy snowfall for Washington and Oregon is expected to continue through Thursday, with several more feet of new powder at further lowering snow levels. Epic!
A late-night update this time! Another day-and-half later, and 3 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict heavy snowfall through Thursday with additional snowfall of 2-4 ft over the rest of this week for Washington, Oregon, and southwest BC. This is all on top of 2-10 ft of snow which has already fallen over the past 12+ days since this storm cycle began on February 6 at most mountain measurement sites along the Pacific coast from Alyeska near Anchorage, Alaska, all the way south to Mammoth Mountain, a span of about 2100 miles as the crow flies (and over 3100 miles by car ). The snowfall over this vast distance is all due to low-pressure systems spawned from the same upper-level parent low in the Gulf of Alaska which has been associated with this entire storm cycle.
This one is now solidly in the HUGE storm cycle category with snowfall amounts reaching 10 ft at several measurement sites already as of Tuesday evening (see the extensive table in the previous post), and 16-day snowfall totals through the end of this week certain to exceed 10-12 ft at many sites especially above 4000-5000 ft in the Washington and northern Oregon Cascades plus southwestern BC. Overall, this storm cycle has been another big win for the predictive capabilities of the weather models especially the UW model, with almost everything throughout the past 2 weeks proceeding reasonably similar to model predictions made 4-7 days ahead (the range of accurate numerical weather prediction), and no major errors or unexpected surprises yet.
The NWS's GFS model and their Quantitative Precipitation Forecasts still show up to 2-4" more precip over the rest of this week for the mountains of Washington and northern Oregon, with 1-2" in southwestern BC , and much smaller amounts of only a fraction of an inch extending south into the California Cascades and northern Sierra. Here is total precipitation in inches predicted over the next 7 days through Tuesday afternoon, February 25, with most of that shown in the Pacific Northwest falling in the next 4 days though Saturday:
Another strong system arrived on Tuesday morning, once again aimed at southwestern BC and Washington, then shifted southward to Oregon by the afternoon and eventually into northernmost California overnight. This system produced another 1-2 ft of snowfall in less than 16 hours at many sites in southwestern BC, Washington, and northern Oregon, on top of 2-3 ft that had fallen the previous day. The next weaker wave of snowfall will come ashore on Wednesday morning, then the next strong system is projected to arrive late Wednesday into southwestern BC and Washington again, lasting through the day Thursday with snowfall again shifting into Oregon, with some light snowfall lingering into Friday.
Snowfall during the next 3 days through 4pm Friday is predicted to be 2-4 ft over the west slopes and volcanic peaks of the Washington and northern Oregon Cascades, the Olympics, and south-central BC coast, with 1-2 ft in southwestern BC and the southern Oregon Cascades, and perhaps up to 6" extending into the California Cascades and Trinity Alps tonight:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 4 ft (marked by white inside yellow) are shown only high up on Mounts Hood, Jefferson, and the Three Sisters in Oregon, with 3-4 ft along the west slopes and volcanic peaks of the Washington Cascades and other areas of the Oregon Cascades plus the Olympics.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Friday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with snowfall amounts decreasing a bit in later runs, but no major changes other than a significant reduction in snowfall for northern California:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022200///+-st
Friday is predicted to be a lull between systems, but then an additional system is expected to come ashore from the northwest early Saturday. Additional snowfall during the subsequent 3 days ending 4pm next Monday is predicted to be another 1-2 ft over the Washington Cascades and southwestern BC, with perhaps several inches extending into northern Oregon:
This represents an extension of this storm cycle from earlier model runs several days ago (but similar to predictions over the last 2 days), by roughly 24-48 hours and mainly in the Washington Cascades and southwestern BC, where the northwesterly jet stream shifting eastward onto the Pacific coast is predicted produce an additional moderate system on Saturday. This storm cycle just doesn't seem to want to fade away quietly! Looking at the jet stream predictions (see Days 1-5 Jet Stream Analysis & Forecasts ), it appears that this final storm's development is predicted to occur in the favorable right entrance region of the eastward-departing jet:
The predictions for this period have been changing significantly on subsequent model runs, which often happens during the period following a major storm or storm cycle, as the details of the evolution of those storms has a large effect on predicted and actual weather for the next few days afterward. So it's best not to give too much weight to the predictions for that additional final system on this weekend, until at least another day or so has passed and the models become more consistent in their predictions.
including 2-4 ft in the past 48 hours, with an additional 2-4 ft predicted the rest of this week for WA, OR, and southwest BC!
The climax of this storm cycle has been going off in the Pacific Northwest the past 2 days, the most intense period of snowfall thus far in the 2013-14 season! The heavy snowfall for Washington and Oregon is expected to continue through Thursday, with several more feet of new powder at further lowering snow levels. Epic!
A late-night update this time! Another day-and-half later, and 3 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict heavy snowfall through Thursday with additional snowfall of 2-4 ft over the rest of this week for Washington, Oregon, and southwest BC. This is all on top of 2-10 ft of snow which has already fallen over the past 12+ days since this storm cycle began on February 6 at most mountain measurement sites along the Pacific coast from Alyeska near Anchorage, Alaska, all the way south to Mammoth Mountain, a span of about 2100 miles as the crow flies (and over 3100 miles by car ). The snowfall over this vast distance is all due to low-pressure systems spawned from the same upper-level parent low in the Gulf of Alaska which has been associated with this entire storm cycle.
This one is now solidly in the HUGE storm cycle category with snowfall amounts reaching 10 ft at several measurement sites already as of Tuesday evening (see the extensive table in the previous post), and 16-day snowfall totals through the end of this week certain to exceed 10-12 ft at many sites especially above 4000-5000 ft in the Washington and northern Oregon Cascades plus southwestern BC. Overall, this storm cycle has been another big win for the predictive capabilities of the weather models especially the UW model, with almost everything throughout the past 2 weeks proceeding reasonably similar to model predictions made 4-7 days ahead (the range of accurate numerical weather prediction), and no major errors or unexpected surprises yet.
The NWS's GFS model and their Quantitative Precipitation Forecasts still show up to 2-4" more precip over the rest of this week for the mountains of Washington and northern Oregon, with 1-2" in southwestern BC , and much smaller amounts of only a fraction of an inch extending south into the California Cascades and northern Sierra. Here is total precipitation in inches predicted over the next 7 days through Tuesday afternoon, February 25, with most of that shown in the Pacific Northwest falling in the next 4 days though Saturday:
Another strong system arrived on Tuesday morning, once again aimed at southwestern BC and Washington, then shifted southward to Oregon by the afternoon and eventually into northernmost California overnight. This system produced another 1-2 ft of snowfall in less than 16 hours at many sites in southwestern BC, Washington, and northern Oregon, on top of 2-3 ft that had fallen the previous day. The next weaker wave of snowfall will come ashore on Wednesday morning, then the next strong system is projected to arrive late Wednesday into southwestern BC and Washington again, lasting through the day Thursday with snowfall again shifting into Oregon, with some light snowfall lingering into Friday.
Snowfall during the next 3 days through 4pm Friday is predicted to be 2-4 ft over the west slopes and volcanic peaks of the Washington and northern Oregon Cascades, the Olympics, and south-central BC coast, with 1-2 ft in southwestern BC and the southern Oregon Cascades, and perhaps up to 6" extending into the California Cascades and Trinity Alps tonight:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 4 ft (marked by white inside yellow) are shown only high up on Mounts Hood, Jefferson, and the Three Sisters in Oregon, with 3-4 ft along the west slopes and volcanic peaks of the Washington Cascades and other areas of the Oregon Cascades plus the Olympics.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Friday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with snowfall amounts decreasing a bit in later runs, but no major changes other than a significant reduction in snowfall for northern California:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022200///+-st
Friday is predicted to be a lull between systems, but then an additional system is expected to come ashore from the northwest early Saturday. Additional snowfall during the subsequent 3 days ending 4pm next Monday is predicted to be another 1-2 ft over the Washington Cascades and southwestern BC, with perhaps several inches extending into northern Oregon:
This represents an extension of this storm cycle from earlier model runs several days ago (but similar to predictions over the last 2 days), by roughly 24-48 hours and mainly in the Washington Cascades and southwestern BC, where the northwesterly jet stream shifting eastward onto the Pacific coast is predicted produce an additional moderate system on Saturday. This storm cycle just doesn't seem to want to fade away quietly! Looking at the jet stream predictions (see Days 1-5 Jet Stream Analysis & Forecasts ), it appears that this final storm's development is predicted to occur in the favorable right entrance region of the eastward-departing jet:
The predictions for this period have been changing significantly on subsequent model runs, which often happens during the period following a major storm or storm cycle, as the details of the evolution of those storms has a large effect on predicted and actual weather for the next few days afterward. So it's best not to give too much weight to the predictions for that additional final system on this weekend, until at least another day or so has passed and the models become more consistent in their predictions.
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20 Feb 2014 17:04 - 08 Mar 2014 09:39 #220634
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-12 ft snow Feb6-21,2014!
Update #12: 336 hours (2 weeks) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
including 4-8 ft in the past 5 days for WA, OR, and southwest BC, with an additional 1-2 ft predicted through Monday!
[size=small]Enjoyed an outstanding powder day at Crystal Mountain yesterday, yo-yoing over 50,000 vert in 30 deep powder laps off Rainier Express and the gondola, with at least some untracked powder on every run right through day's end. About 12-24" of new snow (very cold and dry, almost true blower pow, but medium-low density due to winds aloft during the snowfall) sitting atop about 4 ft of recent snow, and another 3-4" new falling throughout the day. Shockingly there were no crowds or lines at all after 9:30am following the morning rush, and the whole place was basically empty after 11am (maybe most people were waiting in line at High Campbell! I stayed away from that). It felt like a throwback to the halcyon seasons of yore (roughly pre-2009) when midweek powder days at Crystal were actually enjoyable and uncrowded and hassle-free, not the crazy overcrowded zoo that it often is nowadays given the increase in job-flexibility for so many people. Easily my best lift-served day of the last couple seasons, and nicely making up for Monday's nightmare with 6 hours of driving in heavy traffic and no skiing at all due to Crystal's power outage closure. Anyway, on to the update:[/size]
[size=small]Crystal Mountain powder day, snowing hard at noon, February 19.[/size]
[size=small]Crystal Mountain powder day, still semi-untracked in the right places on the last lap at 3:45pm, February 19.[/size]
The final days of this lengthy storm cycle have arrived, following the most intense period of snowfall thus far in the 2013-14 season in the Pacific Northwest over the past 5 days, with several feet of new powder at lowering snow levels! The heavy snowfall for Washington and Oregon is expected to continue through Thursday into early Friday, with a final burst of snowfall over the weekend into Monday.
Another day-and-half later, and 3 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict heavy snowfall through Thursday, a lull on Friday afternoon into Saturday, and then the final system of this storm cycle over the weekend, with additional snowfall of 1-2 ft through Monday for Washington, Oregon, and southwest BC. This is on top of 2-12 ft of snow which has already fallen over the past 14 days since this storm cycle began on February 6 at most mountain measurement sites along the Pacific coast from Alyeska near Anchorage, Alaska, all the way south to Mammoth Mountain, a span of about 2100 miles as the crow flies (and over 3100 miles by car ). The snowfall over this vast distance is all due to low-pressure systems spawned from the same upper-level parent low in the Gulf of Alaska which has been associated with this entire storm cycle.
This one is now solidly in the HUGE storm cycle category with 14-day total snowfall amounts reaching 10-12 ft at several measurement sites already as of Thursday, and final snowfall totals through Monday certain to reach that mark at many other sites especially above 4000-5000 ft in the Washington and northern Oregon Cascades plus southwestern BC. Overall, this storm cycle has been another big win for the predictive capabilities of the weather models especially the UW model, with almost everything throughout the past 2 weeks proceeding reasonably similar to model predictions made 4-7 days ahead (the range of accurate numerical weather prediction), and no major errors or unexpected surprises yet. Perhaps the biggest surprise has been the predicted continuation of this storm cycle through the weekend, with a final moderate system now looking very likely to develop in northwesterly flow on Saturday and last through Monday.
Over the last 2 days, another strong system arrived on Tuesday morning, once again aimed at southwestern BC and Washington, then shifted southward to Oregon by the afternoon and eventually into northernmost California overnight. This system produced another 1-2 ft of snowfall in 24 hours at many sites in southwestern BC, Washington, and northern Oregon, on top of 2-3 ft that had fallen the previous day. A weaker wave of snowfall came ashore on Wednesday morning, then the final strong system arrived late Wednesday into southwestern BC and Washington again, lasting through the day Thursday with snowfall again shifting into Oregon, with some light snowfall expected to linger into Friday. New snowfall amounts have once again topped 1-2 ft in 36 hours from early Wednesday through Thursday afternoon at many sites from Stevens Pass south to Mount Hood, with up to 1 ft in southwestern BC, the North Cascades, and farther south in Oregon, with a few inches extending down to Crater Lake. Beyond that in northern California, this storm cycle had effectively ended long ago with only a few inches of snow overnight Tuesday-Wednesday and skies mostly sunny again for the fifth day in a row since Sunday:
[size=small]Mount Shasta capped by an awesome complex of lenticular clouds on Thursday morning, as seen on the SnowCrest webcam .[/size]
[size=small]Lassen Peak with a lenticular of its own on Thursday afternoon, both reflected in the Manzanita Lake webcam .[/size]
Snowfall during the next 3 days through 4pm Sunday (which catches the end of Thursday's system and the first part of the weekend system) is predicted to be 1-2 ft over Vancouver Island, the Olympics, and northern Washington Cascades, with several inches for much of southwestern BC and only a few inches extending south into the Oregon Cascades tonight:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington:
The most unusual thing about this image is the large area of lowland snowfall predicted from roughly Seattle northward throughout the northern Puget Sound, San Juan Islands, Bellingham area, Vancouver, and the Strait of Georgia, with amounts ranging up to several inches for late Saturday. This is due to the cold air brought in by the strong northwesterly flow over the region (see jet stream graphic at end of the previous post, Update #11 above). It will be interesting to see if this prediction verifies, since lowland snowfall is notoriously difficult to predict accurately in this region.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Sunday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Unlike most of these loops shown previously in this thread, this one has varied wildly in its predictions, especially several days ago, but has become a bit more consistent in the most recent runs. That reflects the uncertainty over how this storm cycle would end, and the unexpected final system now predicted over the weekend:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022400///+-st
Additional snowfall during the subsequent 3 days ending 4pm next Wednesday is predicted to be another 2-8" over the Olympics, Washington Cascades (except the North Cascades), and northern Oregon Cascades. This catches the latter part of the weekend system, and snowfall is expected to end by late Monday or early Tuesday:
Details beyond that point (after the end of this storm cycle) remain murky, with little agreement between models or run-to-run consistency in a single model. A new system may perhaps develop farther south and head into California in the latter half of next week.
Snowpack summary:
Table of snowpack percent of normal at selected sites as of Thursday, February 20. The normal values have been interpolated between the February 15 and March 1 values for those sites for which daily normal values are not available from WRCC . Normal snowdepth values are not available at all for most SNOTEL, BCRFC, and CCSS telemetry sites, since snowdepth sensors were only installed on most of those sites within the past decade. Approximate normal values can be estimated for some of these telemetry sites if they are co-located with a manual snow course which has several decades of snowdepth records near the first of each month. And obviously, the percent of normal will decrease over the next several days as snowfall lessens and the huge amounts of new snow begin to settle and compact. At least until the next big storm cycle!
Feb 20
Current Normal Percent of
Measurement Site Elevation Snowdepth Snowdepth Normal
==== British Columbia ====
Tenquille Lake BCRFC 5480 ft 95" 102" 93% (normals estimated)
Whistler Mountain 5400 ft 91" 91" 100%
Whistler Village 2200 ft 28" 21" 133%
Chilliwack River BCRFC 5320 ft 152" 122" 125%
======= Washington =======
Hurricane Ridge 5250 ft 90" 88" 102%
Mt Baker Ski Area 4200 ft 144" 143" 101%
Rainy Pass SNOTEL 4890 ft 110" 96" 115% (normals estimated)
Mazama 2170 ft 41" 29" 140%
Holden Village 3220 ft 72" 60" 120% ***
Lyman Lake SNOTEL 5980 ft 145" 134" 108% (normals estimated)
Stevens Pass NWAC 3950 ft 126" 96" 131%
Mission Ridge 5160 ft 54" 44" 123%
Snoqualmie Pass 3000 ft 99" 87" 114%
Stampede Pass SNOTEL 3850 ft 103" 94" 110%
Crystal Mtn, Green Valley 6230 ft 133" 97" 137% (only 10 years data)
Crystal Mtn Base 4570 ft 82" 63" 130%
Mt Rainier, Paradise 5400 ft 178" 148" 120%
Mt Rainier, Longmire 2700 ft 29" 32" 91%
White Pass 4440 ft 77" 56" 138%
========= Oregon =========
Mt Hood, Red Hill SNOTEL 4410 ft 88" 82" 107% (normals estimated)
Mt Hood, Timberline Lodge 5880 ft 142" 134" 106%
Mt Hood, Meadows Ski Area 5380 ft 124" 112" 111%
McKenzie SNOTEL 4770 ft 77" 86" 90% (normals estimated)
Three Creeks Meadow SNOTEL 5690 ft 41" 43" 95% (normals estimated)
Mt Bachelor, West Village 6300 ft 117" 94" 125% (normals estimated)
Cascade Summit SNOTEL 5100 ft 55" 66" 83% (normals estimated)
Diamond Peak, Summit Lake 5610 ft 60" 92" 65% (normals estimated)
Crater Lake, Park HQ 6470 ft 57" 107" 53%
Crater Lake, Annie Springs 6000 ft 45" 93" 48% (normals estimated)
Pelican Butte, Cold Springs 5940 ft 32" 74" 43% (normals estimated)
Mt McLoughlin, Fourmile Lake 5970 ft 27" 56" 48% (normals estimated)
======= California =======
Medicine Lake 6700 ft 11" 60" 18% (normals estimated)
Mt Shasta, Old Ski Bowl 7600 ft 28" 103" 27% (normals estimated)
Mt Shasta, Sand Flat 6750 ft 14" 88" 16% (normals estimated)
[size=small]*** I was shocked to discover right now while compiling this table that February 20 happens to be the date of maximum average snowdepth at Holden Village -- most mountain sites above 3000 ft in the WA Cascades have their maximum average snowdepth in mid-March or later, typically around April 1 and as late as mid-April at some high elevation sites. February 20 seems almost freakishly early in comparison, although the maximum average snowdepth does tend to occur in February at lower elevation sites like Mazama.[/size]
As I expected several days ago (see Update #9 above), snowdepths in southwestern BC, the Olympics, Washington Cascades, and northern Oregon Cascades are now at or above normal at sites above about 2000 ft in BC, 3000 ft in WA, and 5000 ft in northern OR. Snowdepths in the southern Oregon Cascades remain far below normal, while those in the California Cascades are still catastrophically below normal even at the highest elevation measurement sites.
The 178" at Mount Rainier Paradise is apparently now the largest snowdepth of any telemetry site in North America (as far as I know, unless I missed something), a familiar position for Paradise in many a season. Other telemetry sites in the same ballpark (over 140") not listed in the table above include the Brown Top SNOTEL (5800 ft near Mount Redoubt in the North Cascades) at 153", Stevens Pass with at Grace Lakes (4800 ft) at 164" and top of Skyline (5250 ft) at 145", Paradise SNOTEL (5120 ft) at 165", and the top of White Pass Ski Area (5800 ft) with the NWAC site at 163" and the adjacent Pigtail Peak SNOTEL at 160". Manually measured sites in that range include 163" atop Pan Dome (5000 ft) at Mount Baker Ski Area, 168" atop Alpental (5470 ft), and 150" at Mount Bachelor mid-mountain (7300 ft).
including 4-8 ft in the past 5 days for WA, OR, and southwest BC, with an additional 1-2 ft predicted through Monday!
[size=small]Enjoyed an outstanding powder day at Crystal Mountain yesterday, yo-yoing over 50,000 vert in 30 deep powder laps off Rainier Express and the gondola, with at least some untracked powder on every run right through day's end. About 12-24" of new snow (very cold and dry, almost true blower pow, but medium-low density due to winds aloft during the snowfall) sitting atop about 4 ft of recent snow, and another 3-4" new falling throughout the day. Shockingly there were no crowds or lines at all after 9:30am following the morning rush, and the whole place was basically empty after 11am (maybe most people were waiting in line at High Campbell! I stayed away from that). It felt like a throwback to the halcyon seasons of yore (roughly pre-2009) when midweek powder days at Crystal were actually enjoyable and uncrowded and hassle-free, not the crazy overcrowded zoo that it often is nowadays given the increase in job-flexibility for so many people. Easily my best lift-served day of the last couple seasons, and nicely making up for Monday's nightmare with 6 hours of driving in heavy traffic and no skiing at all due to Crystal's power outage closure. Anyway, on to the update:[/size]
[size=small]Crystal Mountain powder day, snowing hard at noon, February 19.[/size]
[size=small]Crystal Mountain powder day, still semi-untracked in the right places on the last lap at 3:45pm, February 19.[/size]
The final days of this lengthy storm cycle have arrived, following the most intense period of snowfall thus far in the 2013-14 season in the Pacific Northwest over the past 5 days, with several feet of new powder at lowering snow levels! The heavy snowfall for Washington and Oregon is expected to continue through Thursday into early Friday, with a final burst of snowfall over the weekend into Monday.
Another day-and-half later, and 3 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict heavy snowfall through Thursday, a lull on Friday afternoon into Saturday, and then the final system of this storm cycle over the weekend, with additional snowfall of 1-2 ft through Monday for Washington, Oregon, and southwest BC. This is on top of 2-12 ft of snow which has already fallen over the past 14 days since this storm cycle began on February 6 at most mountain measurement sites along the Pacific coast from Alyeska near Anchorage, Alaska, all the way south to Mammoth Mountain, a span of about 2100 miles as the crow flies (and over 3100 miles by car ). The snowfall over this vast distance is all due to low-pressure systems spawned from the same upper-level parent low in the Gulf of Alaska which has been associated with this entire storm cycle.
This one is now solidly in the HUGE storm cycle category with 14-day total snowfall amounts reaching 10-12 ft at several measurement sites already as of Thursday, and final snowfall totals through Monday certain to reach that mark at many other sites especially above 4000-5000 ft in the Washington and northern Oregon Cascades plus southwestern BC. Overall, this storm cycle has been another big win for the predictive capabilities of the weather models especially the UW model, with almost everything throughout the past 2 weeks proceeding reasonably similar to model predictions made 4-7 days ahead (the range of accurate numerical weather prediction), and no major errors or unexpected surprises yet. Perhaps the biggest surprise has been the predicted continuation of this storm cycle through the weekend, with a final moderate system now looking very likely to develop in northwesterly flow on Saturday and last through Monday.
Over the last 2 days, another strong system arrived on Tuesday morning, once again aimed at southwestern BC and Washington, then shifted southward to Oregon by the afternoon and eventually into northernmost California overnight. This system produced another 1-2 ft of snowfall in 24 hours at many sites in southwestern BC, Washington, and northern Oregon, on top of 2-3 ft that had fallen the previous day. A weaker wave of snowfall came ashore on Wednesday morning, then the final strong system arrived late Wednesday into southwestern BC and Washington again, lasting through the day Thursday with snowfall again shifting into Oregon, with some light snowfall expected to linger into Friday. New snowfall amounts have once again topped 1-2 ft in 36 hours from early Wednesday through Thursday afternoon at many sites from Stevens Pass south to Mount Hood, with up to 1 ft in southwestern BC, the North Cascades, and farther south in Oregon, with a few inches extending down to Crater Lake. Beyond that in northern California, this storm cycle had effectively ended long ago with only a few inches of snow overnight Tuesday-Wednesday and skies mostly sunny again for the fifth day in a row since Sunday:
[size=small]Mount Shasta capped by an awesome complex of lenticular clouds on Thursday morning, as seen on the SnowCrest webcam .[/size]
[size=small]Lassen Peak with a lenticular of its own on Thursday afternoon, both reflected in the Manzanita Lake webcam .[/size]
Snowfall during the next 3 days through 4pm Sunday (which catches the end of Thursday's system and the first part of the weekend system) is predicted to be 1-2 ft over Vancouver Island, the Olympics, and northern Washington Cascades, with several inches for much of southwestern BC and only a few inches extending south into the Oregon Cascades tonight:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington:
The most unusual thing about this image is the large area of lowland snowfall predicted from roughly Seattle northward throughout the northern Puget Sound, San Juan Islands, Bellingham area, Vancouver, and the Strait of Georgia, with amounts ranging up to several inches for late Saturday. This is due to the cold air brought in by the strong northwesterly flow over the region (see jet stream graphic at end of the previous post, Update #11 above). It will be interesting to see if this prediction verifies, since lowland snowfall is notoriously difficult to predict accurately in this region.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Sunday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Unlike most of these loops shown previously in this thread, this one has varied wildly in its predictions, especially several days ago, but has become a bit more consistent in the most recent runs. That reflects the uncertainty over how this storm cycle would end, and the unexpected final system now predicted over the weekend:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022400///+-st
Additional snowfall during the subsequent 3 days ending 4pm next Wednesday is predicted to be another 2-8" over the Olympics, Washington Cascades (except the North Cascades), and northern Oregon Cascades. This catches the latter part of the weekend system, and snowfall is expected to end by late Monday or early Tuesday:
Details beyond that point (after the end of this storm cycle) remain murky, with little agreement between models or run-to-run consistency in a single model. A new system may perhaps develop farther south and head into California in the latter half of next week.
Snowpack summary:
Table of snowpack percent of normal at selected sites as of Thursday, February 20. The normal values have been interpolated between the February 15 and March 1 values for those sites for which daily normal values are not available from WRCC . Normal snowdepth values are not available at all for most SNOTEL, BCRFC, and CCSS telemetry sites, since snowdepth sensors were only installed on most of those sites within the past decade. Approximate normal values can be estimated for some of these telemetry sites if they are co-located with a manual snow course which has several decades of snowdepth records near the first of each month. And obviously, the percent of normal will decrease over the next several days as snowfall lessens and the huge amounts of new snow begin to settle and compact. At least until the next big storm cycle!
Feb 20
Current Normal Percent of
Measurement Site Elevation Snowdepth Snowdepth Normal
==== British Columbia ====
Tenquille Lake BCRFC 5480 ft 95" 102" 93% (normals estimated)
Whistler Mountain 5400 ft 91" 91" 100%
Whistler Village 2200 ft 28" 21" 133%
Chilliwack River BCRFC 5320 ft 152" 122" 125%
======= Washington =======
Hurricane Ridge 5250 ft 90" 88" 102%
Mt Baker Ski Area 4200 ft 144" 143" 101%
Rainy Pass SNOTEL 4890 ft 110" 96" 115% (normals estimated)
Mazama 2170 ft 41" 29" 140%
Holden Village 3220 ft 72" 60" 120% ***
Lyman Lake SNOTEL 5980 ft 145" 134" 108% (normals estimated)
Stevens Pass NWAC 3950 ft 126" 96" 131%
Mission Ridge 5160 ft 54" 44" 123%
Snoqualmie Pass 3000 ft 99" 87" 114%
Stampede Pass SNOTEL 3850 ft 103" 94" 110%
Crystal Mtn, Green Valley 6230 ft 133" 97" 137% (only 10 years data)
Crystal Mtn Base 4570 ft 82" 63" 130%
Mt Rainier, Paradise 5400 ft 178" 148" 120%
Mt Rainier, Longmire 2700 ft 29" 32" 91%
White Pass 4440 ft 77" 56" 138%
========= Oregon =========
Mt Hood, Red Hill SNOTEL 4410 ft 88" 82" 107% (normals estimated)
Mt Hood, Timberline Lodge 5880 ft 142" 134" 106%
Mt Hood, Meadows Ski Area 5380 ft 124" 112" 111%
McKenzie SNOTEL 4770 ft 77" 86" 90% (normals estimated)
Three Creeks Meadow SNOTEL 5690 ft 41" 43" 95% (normals estimated)
Mt Bachelor, West Village 6300 ft 117" 94" 125% (normals estimated)
Cascade Summit SNOTEL 5100 ft 55" 66" 83% (normals estimated)
Diamond Peak, Summit Lake 5610 ft 60" 92" 65% (normals estimated)
Crater Lake, Park HQ 6470 ft 57" 107" 53%
Crater Lake, Annie Springs 6000 ft 45" 93" 48% (normals estimated)
Pelican Butte, Cold Springs 5940 ft 32" 74" 43% (normals estimated)
Mt McLoughlin, Fourmile Lake 5970 ft 27" 56" 48% (normals estimated)
======= California =======
Medicine Lake 6700 ft 11" 60" 18% (normals estimated)
Mt Shasta, Old Ski Bowl 7600 ft 28" 103" 27% (normals estimated)
Mt Shasta, Sand Flat 6750 ft 14" 88" 16% (normals estimated)
[size=small]*** I was shocked to discover right now while compiling this table that February 20 happens to be the date of maximum average snowdepth at Holden Village -- most mountain sites above 3000 ft in the WA Cascades have their maximum average snowdepth in mid-March or later, typically around April 1 and as late as mid-April at some high elevation sites. February 20 seems almost freakishly early in comparison, although the maximum average snowdepth does tend to occur in February at lower elevation sites like Mazama.[/size]
As I expected several days ago (see Update #9 above), snowdepths in southwestern BC, the Olympics, Washington Cascades, and northern Oregon Cascades are now at or above normal at sites above about 2000 ft in BC, 3000 ft in WA, and 5000 ft in northern OR. Snowdepths in the southern Oregon Cascades remain far below normal, while those in the California Cascades are still catastrophically below normal even at the highest elevation measurement sites.
The 178" at Mount Rainier Paradise is apparently now the largest snowdepth of any telemetry site in North America (as far as I know, unless I missed something), a familiar position for Paradise in many a season. Other telemetry sites in the same ballpark (over 140") not listed in the table above include the Brown Top SNOTEL (5800 ft near Mount Redoubt in the North Cascades) at 153", Stevens Pass with at Grace Lakes (4800 ft) at 164" and top of Skyline (5250 ft) at 145", Paradise SNOTEL (5120 ft) at 165", and the top of White Pass Ski Area (5800 ft) with the NWAC site at 163" and the adjacent Pigtail Peak SNOTEL at 160". Manually measured sites in that range include 163" atop Pan Dome (5000 ft) at Mount Baker Ski Area, 168" atop Alpental (5470 ft), and 150" at Mount Bachelor mid-mountain (7300 ft).
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21 Feb 2014 12:36 #220660
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-12 ft snow Feb6-21,2014!
Sunrise after the storm:
With a decent lull between storms on Friday before the final system(s) of this storm cycle arrive over the weekend, skies cleared by sunrise at many mountain locations in southwestern BC, Washington, and Oregon (and remained clear in California), although light to moderate snowfall continued occasionally at other sites, and some of these clear sites soon reverted to snowfall too:
[size=small]Sunrise atop Whistler Mountain, with the volcanic spires of Mount Cayley and the broad icefield domes of Powder Mountain glowing white at center,
as seen on a hidden image formerly linked from the Whistler Peak webcam (2014-02-21 7:23am).[/size]
[size=small]Sunrise from atop 7th Heaven on Blackcomb , with the volcanic peaks of Mount Garibaldi (center) and Black Tusk (right) in the distance.[/size]
[size=small]Sunrise from Hurricane Ridge , with Mount Olympus shining in the sun at center.[/size]
[size=small]Sunrise and cool clouds at Hurricane Ridge , with snow plowing operations in progress -- the road would open by 9:30am
despite several feet of snowfall during the week (road is closed Monday-Thursday in winter).[/size]
[size=small]Sunrise on the peaks of Crystal Mountain .[/size]
[size=small]Sunrise on Mount Rainier from atop Crystal Mountain , with some interesting thin stacked lenticular clouds above the summit.[/size]
[size=small]Just a brief glimpse of the Mountain from the other side at Paradise .[/size]
[size=small]Rising run, setting moon, snow-drifted parking lot at Paradise .[/size]
[size=small]Sunrise on Mount Hood from the Columbia River Gorge .[/size]
[size=small]Clouds parting after sunrise to reveal North Sister and Middle Sister, as seen on the Cascade Flyers webcam between Bend and Sisters (2014-02-21 8:58am).[/size]
[size=small]Clouds parting by late-morning to reveal South Sister, Middle Sister, North Sister, and Broken Top (left to right) as seen from Mount Bachelor .[/size]
[size=small]The Crater Lake webcam finally defrosted enough by noon to reveal Wizard Island.[/size]
[size=small]Distant view of sunrise on Mount Shasta from 60 miles NE in Klamath Falls .[/size]
[size=small]Sunrise from the southwest entrance of Lassen Volcanic National Park .[/size]
With a decent lull between storms on Friday before the final system(s) of this storm cycle arrive over the weekend, skies cleared by sunrise at many mountain locations in southwestern BC, Washington, and Oregon (and remained clear in California), although light to moderate snowfall continued occasionally at other sites, and some of these clear sites soon reverted to snowfall too:
[size=small]Sunrise atop Whistler Mountain, with the volcanic spires of Mount Cayley and the broad icefield domes of Powder Mountain glowing white at center,
as seen on a hidden image formerly linked from the Whistler Peak webcam (2014-02-21 7:23am).[/size]
[size=small]Sunrise from atop 7th Heaven on Blackcomb , with the volcanic peaks of Mount Garibaldi (center) and Black Tusk (right) in the distance.[/size]
[size=small]Sunrise from Hurricane Ridge , with Mount Olympus shining in the sun at center.[/size]
[size=small]Sunrise and cool clouds at Hurricane Ridge , with snow plowing operations in progress -- the road would open by 9:30am
despite several feet of snowfall during the week (road is closed Monday-Thursday in winter).[/size]
[size=small]Sunrise on the peaks of Crystal Mountain .[/size]
[size=small]Sunrise on Mount Rainier from atop Crystal Mountain , with some interesting thin stacked lenticular clouds above the summit.[/size]
[size=small]Just a brief glimpse of the Mountain from the other side at Paradise .[/size]
[size=small]Rising run, setting moon, snow-drifted parking lot at Paradise .[/size]
[size=small]Sunrise on Mount Hood from the Columbia River Gorge .[/size]
[size=small]Clouds parting after sunrise to reveal North Sister and Middle Sister, as seen on the Cascade Flyers webcam between Bend and Sisters (2014-02-21 8:58am).[/size]
[size=small]Clouds parting by late-morning to reveal South Sister, Middle Sister, North Sister, and Broken Top (left to right) as seen from Mount Bachelor .[/size]
[size=small]The Crater Lake webcam finally defrosted enough by noon to reveal Wizard Island.[/size]
[size=small]Distant view of sunrise on Mount Shasta from 60 miles NE in Klamath Falls .[/size]
[size=small]Sunrise from the southwest entrance of Lassen Volcanic National Park .[/size]
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21 Feb 2014 15:06 #220665
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
Update #13: 360 hours (15 days) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
with an additional 1-3 ft predicted through Tuesday including the possibility of lowland snowfall in western Washington!
The final stage of this lengthy storm cycle has arrived, following the most intense period of snowfall thus far in the 2013-14 season in the Pacific Northwest over the past 6 days, with several feet of new powder at lowering snow levels! The last systems of this storm cycle are expected to come over the weekend and into the start of next week, providing a final burst of snowfall for Washington and northern Oregon over the weekend into Tuesday.
Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict a surprising conclusion to this storm cycle: TWO MORE shots of snow over the weekend into next week, including a significant chance of lowland snowfall in western Washington both times. The TV news has quickly latched onto this possibility, and panic may be about to set in once again in this region.
The jet stream (see Days 1-5 Jet Stream Analysis & Forecasts ) is still the key to what is likely to happen. By Saturday, the tail end of the strong jet stream which brought so much snowfall this week will have shifted eastward over the BC coast and be coming in from the north-northwest directly over Washington state, bringing the first shot of snow down from that direction (compare with the same image in Update #11 above, this image is almost identical to the prediction 3 days earlier):
By late Sunday and into Monday, the jet stream pattern will have evolved and shifted south and east over the central part of the continent, with only the entrance region of the jet over the Northwest, allowing another system to develop in that region and entrain some moisture from the southwest, providing a second shot at snow at that time:
By Wednesday, that jet has departed, this storm cycle is long over, and a new jet is about to land in California, where jets bearing large quantities of moisture are currently most welcome to land:
This large animated GIF image (47 frames like the image above, 2.6 MB) shows the entire evolution of the jet stream during this storm cycle at 12-hour intervals, from February 3 a few days before it started through today, plus predictions for the next 5 days through Wednesday, February 26. I think it's a fascinating way to watch how this entire complicated storm cycle originated and then played out:
www.skimountaineer.com/TR/Images2014/jetstream_pac-Feb2014.gif
The NWS's GFS model and their Quantitative Precipitation Forecasts are now showing up to 4-5" of precip in California from that new storm cycle next week, which is great news for that severely drought-stricken region. Here is total precipitation in inches predicted over the next 7 days through Friday afternoon, February 28, with almost all of that shown in the Pacific Northwest falling in the next 3+ days though Monday in Washington and early Tuesday in Oregon, and all of that in California during the 5-7 day period from Wednesday onward:
Snowfall during the next 3 days through 4pm Monday (which catches all but the tail end of the weekend systems) is predicted to be about 1 ft over most of the Washington Cascades and Olympics (more like 1-3 ft in the central Cascades and Mount Rainier), with several inches over southwestern BC and the northern Oregon Cascades:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 2-3 ft are shown on Mount Rainier, with large areas of 1-2 ft in the central WA Cascades and also high up on Mount Jefferson and the Three Sisters in Oregon.
The most unusual thing about the Washington image is the large area of lowland snowfall predicted over most of western Washington. This snowfall is expected in two shots, on Saturday from roughly Seattle northward throughout the northern Puget Sound, San Juan Islands, Bellingham area, Vancouver, and the Strait of Georgia, with amounts ranging up to several inches, and then a second shot farther south on Sunday night into Monday for the Seattle area and southwest Washington. It will be interesting to see if these predictions verify, since lowland snowfall is notoriously difficult to predict accurately in this region. Forecasts for lowland snow can go haywire at any time here.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Monday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Unlike most of these loops shown previously in this thread (but similar to yesterday's), this one has varied wildly in its predictions, especially several days ago, but has become much more consistent in the most recent runs. That reflects the uncertainty over how this storm cycle would end, and the unexpected final systems now predicted over the weekend and into week:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022500///+-st
The next storm cycle is predicted to begin on Wednesday, with systems arriving from the southwest into northern California and southern Oregon over the rest of next week. It's another Pineapple Express type of atmospheric river event, although perhaps not as intense as the one which kicked off this storm cycle. Snowfall from that new storm cycle during the 3-day period ending 4pm next Friday is predicted to be up to 3-4 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, with lesser amounts in Oregon and very little extending north into Washington over that time period:
But that's a story for another storm cycle thread (maybe, maybe not -- I'm not sure if I'll actually bother writing about that one). And it's still 5-7 days out, near the limit of accurate numerical weather prediction, so that storm cycle is no sure thing quite yet.
with an additional 1-3 ft predicted through Tuesday including the possibility of lowland snowfall in western Washington!
The final stage of this lengthy storm cycle has arrived, following the most intense period of snowfall thus far in the 2013-14 season in the Pacific Northwest over the past 6 days, with several feet of new powder at lowering snow levels! The last systems of this storm cycle are expected to come over the weekend and into the start of next week, providing a final burst of snowfall for Washington and northern Oregon over the weekend into Tuesday.
Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict a surprising conclusion to this storm cycle: TWO MORE shots of snow over the weekend into next week, including a significant chance of lowland snowfall in western Washington both times. The TV news has quickly latched onto this possibility, and panic may be about to set in once again in this region.
The jet stream (see Days 1-5 Jet Stream Analysis & Forecasts ) is still the key to what is likely to happen. By Saturday, the tail end of the strong jet stream which brought so much snowfall this week will have shifted eastward over the BC coast and be coming in from the north-northwest directly over Washington state, bringing the first shot of snow down from that direction (compare with the same image in Update #11 above, this image is almost identical to the prediction 3 days earlier):
By late Sunday and into Monday, the jet stream pattern will have evolved and shifted south and east over the central part of the continent, with only the entrance region of the jet over the Northwest, allowing another system to develop in that region and entrain some moisture from the southwest, providing a second shot at snow at that time:
By Wednesday, that jet has departed, this storm cycle is long over, and a new jet is about to land in California, where jets bearing large quantities of moisture are currently most welcome to land:
This large animated GIF image (47 frames like the image above, 2.6 MB) shows the entire evolution of the jet stream during this storm cycle at 12-hour intervals, from February 3 a few days before it started through today, plus predictions for the next 5 days through Wednesday, February 26. I think it's a fascinating way to watch how this entire complicated storm cycle originated and then played out:
www.skimountaineer.com/TR/Images2014/jetstream_pac-Feb2014.gif
The NWS's GFS model and their Quantitative Precipitation Forecasts are now showing up to 4-5" of precip in California from that new storm cycle next week, which is great news for that severely drought-stricken region. Here is total precipitation in inches predicted over the next 7 days through Friday afternoon, February 28, with almost all of that shown in the Pacific Northwest falling in the next 3+ days though Monday in Washington and early Tuesday in Oregon, and all of that in California during the 5-7 day period from Wednesday onward:
Snowfall during the next 3 days through 4pm Monday (which catches all but the tail end of the weekend systems) is predicted to be about 1 ft over most of the Washington Cascades and Olympics (more like 1-3 ft in the central Cascades and Mount Rainier), with several inches over southwestern BC and the northern Oregon Cascades:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 2-3 ft are shown on Mount Rainier, with large areas of 1-2 ft in the central WA Cascades and also high up on Mount Jefferson and the Three Sisters in Oregon.
The most unusual thing about the Washington image is the large area of lowland snowfall predicted over most of western Washington. This snowfall is expected in two shots, on Saturday from roughly Seattle northward throughout the northern Puget Sound, San Juan Islands, Bellingham area, Vancouver, and the Strait of Georgia, with amounts ranging up to several inches, and then a second shot farther south on Sunday night into Monday for the Seattle area and southwest Washington. It will be interesting to see if these predictions verify, since lowland snowfall is notoriously difficult to predict accurately in this region. Forecasts for lowland snow can go haywire at any time here.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Monday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Unlike most of these loops shown previously in this thread (but similar to yesterday's), this one has varied wildly in its predictions, especially several days ago, but has become much more consistent in the most recent runs. That reflects the uncertainty over how this storm cycle would end, and the unexpected final systems now predicted over the weekend and into week:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022500///+-st
The next storm cycle is predicted to begin on Wednesday, with systems arriving from the southwest into northern California and southern Oregon over the rest of next week. It's another Pineapple Express type of atmospheric river event, although perhaps not as intense as the one which kicked off this storm cycle. Snowfall from that new storm cycle during the 3-day period ending 4pm next Friday is predicted to be up to 3-4 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, with lesser amounts in Oregon and very little extending north into Washington over that time period:
But that's a story for another storm cycle thread (maybe, maybe not -- I'm not sure if I'll actually bother writing about that one). And it's still 5-7 days out, near the limit of accurate numerical weather prediction, so that storm cycle is no sure thing quite yet.
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22 Feb 2014 13:23 - 22 Feb 2014 16:12 #220687
by Amar Andalkar
As expected, the road did open to the public on Saturday just after 10am . If the weather had been nicer, I probably would have gone up there for a look-see, but the thick clouds and whiteout nixed that idea.
As of Friday morning, the Paradise parking lot had been partially plowed the day before, then refilled that evening and overnight due to additional snowfall and wind-drifitng:
The lot was re-plowed almost completely before noon on Friday, but then plowing operations stopped as apparently it had been decided not to open the road that day. It certainly appears that the road could have opened Friday afternoon (not counting law enforcement staffing and other concerns):
The final bits were plowed out early Saturday, and the road opened a few hours later:
It's nice to have access once again to what is now by far the deepest road-accessible snowpack in North America, probably in the world, with 168" (14 ft) as of this morning following some settlement from the maximum value of 178" on February 20. Unless someplace in the snow belt on the west side of the Japanese Alps or Hokkaido currently has more. This table of Japanese ski resort snow depths shows several areas reporting over 430 cm / 169" today, but it's unclear if the depths listed in this table are at their bases or a higher station. A quick check of the Geto Kogen website reveals that the 540 cm / 213" depth is actually at their summit, with only 405 cm / 159" at the base, and similarly for Charmant Hiuchi . Here are the largest snowdepths as of February 22 at any Japanese ski resorts:
Summit Summit Base Base
Elevation Snow Depth Elevation Snow Depth
Geto Kogen 3500 ft 540 cm / 213" 2100 ft 405 cm / 159"
Charmant Hiuchi 3300 ft 460 cm / 181" 1650 ft 363 cm / 143"
Kiroro Snow World 3850 ft 450 cm / 177" 1850 ft (only 1 depth listed)
Seki Onsen 3950 ft 450 cm / 177" 2950 ft (only 1 depth listed)
Sapporo Kokusai 3600 ft 430 cm / 169" 2050 ft (only 1 depth listed)
Tanigawadake 4900 ft 430 cm / 169" 2450 ft (only 1 depth listed)
I do not know if any Japanese national parks or highway passes currently have greater snow depths, this would be useful information to know where to find on the web.
Lots of lenticulars:
On another note, there were lots of interesting lenticular clouds out and visible during the lull between systems on Friday afternoon and Saturday morning, produced by the strong northwesterly winds aloft as the jet stream moved over the BC coast and aimed directly down into Washington and northern Oregon. February 21:
[size=small]Several complex lenticulars crown Mount Rainier on Friday afternoon, as seen from atop Crystal Mountain .[/size]
[size=small]Several complex lenticulars crown Mount Hood too on Friday afternoon, looking up from Timberline Lodge .[/size]
February 22:
[size=small]Lenticulars at dawn on Mount Adams, looking NW from a high plateau above the Klickitat River canyon near Lyle (2014-02-22 6:48am).[/size]
[size=small]Sunrise lenticulars on Mount Jefferson, looking south from Timberline Lodge on Mount Hood .[/size]
[size=small]Thin wispy lenticulars forming at sunrise on North Sister and Middle Sister, as seen on the Cascade Flyers webcam between Bend and Sisters (2014-02-22 7:09am).[/size]
[size=small]Thin wispy lenticulars forming at sunrise on South Sister, Middle Sister, North Sister, and maybe even Broken Top (left to right) as seen from Mount Bachelor .
Same time as previous image, looking from the SE instead of the NE.[/size]
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-12 ft snow Feb6-21,2014!
As usual, a nice, detailed report, Amar. The big question is: Will Mt. Rainier open the road to Paradise this month?
I really shouldn't speculate about the road opening, that is not something that any computer model can yet forecast! But here goes:
This month: the road will open for certain again in February, barring some type of catastrophe.
This week: not likely on any weekday given 1-3 ft of new snow expected each day through Thursday.
But the storm cycle fades out around Friday, so a weekend opening seems reasonable (and Friday is perhaps possible).
As expected, the road did open to the public on Saturday just after 10am . If the weather had been nicer, I probably would have gone up there for a look-see, but the thick clouds and whiteout nixed that idea.
As of Friday morning, the Paradise parking lot had been partially plowed the day before, then refilled that evening and overnight due to additional snowfall and wind-drifitng:
The lot was re-plowed almost completely before noon on Friday, but then plowing operations stopped as apparently it had been decided not to open the road that day. It certainly appears that the road could have opened Friday afternoon (not counting law enforcement staffing and other concerns):
The final bits were plowed out early Saturday, and the road opened a few hours later:
It's nice to have access once again to what is now by far the deepest road-accessible snowpack in North America, probably in the world, with 168" (14 ft) as of this morning following some settlement from the maximum value of 178" on February 20. Unless someplace in the snow belt on the west side of the Japanese Alps or Hokkaido currently has more. This table of Japanese ski resort snow depths shows several areas reporting over 430 cm / 169" today, but it's unclear if the depths listed in this table are at their bases or a higher station. A quick check of the Geto Kogen website reveals that the 540 cm / 213" depth is actually at their summit, with only 405 cm / 159" at the base, and similarly for Charmant Hiuchi . Here are the largest snowdepths as of February 22 at any Japanese ski resorts:
Summit Summit Base Base
Elevation Snow Depth Elevation Snow Depth
Geto Kogen 3500 ft 540 cm / 213" 2100 ft 405 cm / 159"
Charmant Hiuchi 3300 ft 460 cm / 181" 1650 ft 363 cm / 143"
Kiroro Snow World 3850 ft 450 cm / 177" 1850 ft (only 1 depth listed)
Seki Onsen 3950 ft 450 cm / 177" 2950 ft (only 1 depth listed)
Sapporo Kokusai 3600 ft 430 cm / 169" 2050 ft (only 1 depth listed)
Tanigawadake 4900 ft 430 cm / 169" 2450 ft (only 1 depth listed)
I do not know if any Japanese national parks or highway passes currently have greater snow depths, this would be useful information to know where to find on the web.
Lots of lenticulars:
On another note, there were lots of interesting lenticular clouds out and visible during the lull between systems on Friday afternoon and Saturday morning, produced by the strong northwesterly winds aloft as the jet stream moved over the BC coast and aimed directly down into Washington and northern Oregon. February 21:
[size=small]Several complex lenticulars crown Mount Rainier on Friday afternoon, as seen from atop Crystal Mountain .[/size]
[size=small]Several complex lenticulars crown Mount Hood too on Friday afternoon, looking up from Timberline Lodge .[/size]
February 22:
[size=small]Lenticulars at dawn on Mount Adams, looking NW from a high plateau above the Klickitat River canyon near Lyle (2014-02-22 6:48am).[/size]
[size=small]Sunrise lenticulars on Mount Jefferson, looking south from Timberline Lodge on Mount Hood .[/size]
[size=small]Thin wispy lenticulars forming at sunrise on North Sister and Middle Sister, as seen on the Cascade Flyers webcam between Bend and Sisters (2014-02-22 7:09am).[/size]
[size=small]Thin wispy lenticulars forming at sunrise on South Sister, Middle Sister, North Sister, and maybe even Broken Top (left to right) as seen from Mount Bachelor .
Same time as previous image, looking from the SE instead of the NE.[/size]
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22 Feb 2014 15:44 - 22 Feb 2014 15:51 #220690
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
Update #14: 384 hours (16 days) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
with an additional 1-3 ft predicted through Tuesday including the (diminishing) possibility of lowland snowfall in western Washington!
Just a brief update this time. Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals still continue to predict an additional 1-3 ft of snowfall over the Washington Cascades through Tuesday morning. However, the chance of any more lowland snow in western Washington either today or Monday has diminished to nearly zero in the recent runs, so a general panic may no longer be necessary in this region.
As predicted, following Friday's lull a system did arrive in northwesterly flow on Saturday morning, including a bit of lowland of snow in northwestern Washington. Amounts were minimal at generally less than 1", the areas that got snow were discontinuous, and scenes like this were typical, with snowy and bare areas interspersed over just a few miles of I-5 from MP 258 to 246 near Bellingham (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is expected to intensify later today and into Sunday morning, with the next system arriving almost immediately afterward on Sunday afternoon and continuing into Monday, while moving southward into northern Oregon. Snowfall during the next 3 days through 4pm Tuesday (which catches all the remaining parts of the weekend systems) is predicted to be about 1 ft over most of the Washington Cascades and Olympics (more like 1-3 ft in the central Cascades and Mount Rainier), with several inches over Vancouver Island and the northern Oregon Cascades, and very little over the mainland of southwestern BC:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 2-3 ft are shown on Mount Rainier, with large areas of 1-2 ft in the central WA Cascades and also high up in the Three Sisters in Oregon. The lowland snowfall has almost completely vanished from the Washington image compared to 24 hours earlier (see Update #13 above), not unexpectedly at all. The remaining areas of lowland snow are mainly limited to the San Juan Islands and along the Strait of Juan de Fuca. There's still a chance that later model runs might once again predict more widespread lowland snow for Sunday-Monday, or that it might snow anyway in other areas despite model predictions stating that it won't.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Tuesday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with minor variations, which shows that the model had locked on to the solution predicting additional storms this weekend by about 4-5 days ago:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022600///+-st
The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon that morning and then a stronger system on Friday into Saturday. Snowfall from that new storm cycle during the 3-day period ending 4am next Saturday is still predicted to be up to 3-4 ft at higher elevations of the California Cascades and Trinity Alps and 3-5 ft in the Sierra Nevada, with lesser amounts in Oregon and Washington:
Although that's still 4-7 days out and near the limit of accurate numerical weather prediction, the consistency between subsequent model runs indicates that this critically-needed major storm cycle for California is increasingly likely to actually occur.
with an additional 1-3 ft predicted through Tuesday including the (diminishing) possibility of lowland snowfall in western Washington!
Just a brief update this time. Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals still continue to predict an additional 1-3 ft of snowfall over the Washington Cascades through Tuesday morning. However, the chance of any more lowland snow in western Washington either today or Monday has diminished to nearly zero in the recent runs, so a general panic may no longer be necessary in this region.
As predicted, following Friday's lull a system did arrive in northwesterly flow on Saturday morning, including a bit of lowland of snow in northwestern Washington. Amounts were minimal at generally less than 1", the areas that got snow were discontinuous, and scenes like this were typical, with snowy and bare areas interspersed over just a few miles of I-5 from MP 258 to 246 near Bellingham (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is expected to intensify later today and into Sunday morning, with the next system arriving almost immediately afterward on Sunday afternoon and continuing into Monday, while moving southward into northern Oregon. Snowfall during the next 3 days through 4pm Tuesday (which catches all the remaining parts of the weekend systems) is predicted to be about 1 ft over most of the Washington Cascades and Olympics (more like 1-3 ft in the central Cascades and Mount Rainier), with several inches over Vancouver Island and the northern Oregon Cascades, and very little over the mainland of southwestern BC:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 2-3 ft are shown on Mount Rainier, with large areas of 1-2 ft in the central WA Cascades and also high up in the Three Sisters in Oregon. The lowland snowfall has almost completely vanished from the Washington image compared to 24 hours earlier (see Update #13 above), not unexpectedly at all. The remaining areas of lowland snow are mainly limited to the San Juan Islands and along the Strait of Juan de Fuca. There's still a chance that later model runs might once again predict more widespread lowland snow for Sunday-Monday, or that it might snow anyway in other areas despite model predictions stating that it won't.
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Tuesday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with minor variations, which shows that the model had locked on to the solution predicting additional storms this weekend by about 4-5 days ago:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022600///+-st
The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon that morning and then a stronger system on Friday into Saturday. Snowfall from that new storm cycle during the 3-day period ending 4am next Saturday is still predicted to be up to 3-4 ft at higher elevations of the California Cascades and Trinity Alps and 3-5 ft in the Sierra Nevada, with lesser amounts in Oregon and Washington:
Although that's still 4-7 days out and near the limit of accurate numerical weather prediction, the consistency between subsequent model runs indicates that this critically-needed major storm cycle for California is increasingly likely to actually occur.
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23 Feb 2014 11:49 - 24 Feb 2014 13:51 #220713
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
[size=small]Wasn't planning to write an update today as I was intending to ski. But feeling a bit sick for the last couple of days, with a sore throat and now a cough, the first time I've had a cold in a very long time. So unfortunately I'm choosing to miss out on the fine ski conditions. At least I can sit here and watch the snow continue to pile up, deeper and deeper, and keep writing about it too:[/size]
Update #15: 408 hours (17 days) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
with an additional 1-1.5 ft predicted through Tuesday including the (diminishing) possibility of lowland snowfall in western Washington!
Another brief update in the waning days of this storm cycle. Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals still continue to predict up to an additional 1-1.5 ft of snowfall over the Washington Cascades through Tuesday morning. However, the chance of any lowland snow in western Washington south of Bellingham on Sunday night into Monday has diminished to nearly zero over the last 2 days of model runs.
As of Sunday morning, about 3-15" of new snow has been received over the past 24 hours from about Whistler south to Mount Rainier, with only an inch or two farther south to Mount Hood, and clear skies beyond that on Mount Bachelor and into California. The largest new snowfalls were on the North Shore of Vancouver and in parts of the North Cascades with over 1 ft, topped by 15" at Mount Seymour, 13" at Cypress Mountain, 12" at Grouse Mountain, over 15" at the Chilliwack River BCRFC site (5300 ft in the BC Cascades just north of the US border near Mount Baker), 12" at Mount Baker Ski Area, and 14" at Holden Village. This area of maximum snowfall was definitely farther north than the model had predicted, as it had shown 1 ft amounts in the Central Cascades with only a few inches on Mount Baker or the North Shore of Vancouver.
There was a bigger dose of lowland of snow in northwestern Washington overnight and this morning than on Saturday morning, with amounts up to a few inches this time. Definitely more snow and much more continuous snow on these same 3 webcams than yesterday, along I-5 from MP 258 to 246 near Bellingham (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is again expected to intensify later Sunday afternoon and continue through Monday, while moving southward into northern Oregon. Snowfall during the next 3 days through 4am Wednesday (which catches all the remaining parts of the weekend systems) is predicted to be up to 1-1.5 ft over most of the Washington Cascades north of Mount Rainier, with several inches over Vancouver Island, parts of the mainland of southwestern BC, the Olympics, the southern Washington Cascades, and the parts of the northern Oregon Cascades:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 1-1.5 ft are shown on Mount Rainier and large areas of the central WA Cascades and also high up in the Three Sisters in Oregon. The lowland snowfall is still almost completely absent from the Washington image similar to 24 hours earlier (see Update #14 above), with the remaining areas of lowland snow still limited to northwest Washington, the San Juan Islands, and along the Strait of Juan de Fuca. There's still a small chance that it might snow anyway in other areas despite model predictions stating that it won't, but temperatures are likely to remain just too warm farther south than that area.
This loop shows how the model predictions for snowfall during the 3-day period through 4am Wednesday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with minor variations, which shows that the model had locked on to the solution predicting additional storms this weekend by about 5 days ago. The biggest change has been a sharp reduction in snowfall amounts for northern Oregon over the most recent runs, which is primarily due to greater warming down there rather than a large reduction in predicted precip amounts:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022612///+-st
The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon that morning and then another system on Friday into Saturday and Sunday. Snowfall from that new storm cycle during the 3-day period ending 4am next Saturday is now predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, a fairly significant reduction from 24 hours ago:
It still appears likely that this critically-needed major storm cycle for California will actually occur, but details and timing continue to change substantially on subsequent model runs, as do the total snowfall amounts as seen in the D(model)/D(t) for this period, including 4 runs over the last 2 days:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030112///+-st
Update #15: 408 hours (17 days) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
with an additional 1-1.5 ft predicted through Tuesday including the (diminishing) possibility of lowland snowfall in western Washington!
Another brief update in the waning days of this storm cycle. Another day later, and 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals still continue to predict up to an additional 1-1.5 ft of snowfall over the Washington Cascades through Tuesday morning. However, the chance of any lowland snow in western Washington south of Bellingham on Sunday night into Monday has diminished to nearly zero over the last 2 days of model runs.
As of Sunday morning, about 3-15" of new snow has been received over the past 24 hours from about Whistler south to Mount Rainier, with only an inch or two farther south to Mount Hood, and clear skies beyond that on Mount Bachelor and into California. The largest new snowfalls were on the North Shore of Vancouver and in parts of the North Cascades with over 1 ft, topped by 15" at Mount Seymour, 13" at Cypress Mountain, 12" at Grouse Mountain, over 15" at the Chilliwack River BCRFC site (5300 ft in the BC Cascades just north of the US border near Mount Baker), 12" at Mount Baker Ski Area, and 14" at Holden Village. This area of maximum snowfall was definitely farther north than the model had predicted, as it had shown 1 ft amounts in the Central Cascades with only a few inches on Mount Baker or the North Shore of Vancouver.
There was a bigger dose of lowland of snow in northwestern Washington overnight and this morning than on Saturday morning, with amounts up to a few inches this time. Definitely more snow and much more continuous snow on these same 3 webcams than yesterday, along I-5 from MP 258 to 246 near Bellingham (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is again expected to intensify later Sunday afternoon and continue through Monday, while moving southward into northern Oregon. Snowfall during the next 3 days through 4am Wednesday (which catches all the remaining parts of the weekend systems) is predicted to be up to 1-1.5 ft over most of the Washington Cascades north of Mount Rainier, with several inches over Vancouver Island, parts of the mainland of southwestern BC, the Olympics, the southern Washington Cascades, and the parts of the northern Oregon Cascades:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington and Oregon:
Maximum snowfall amounts of about 1-1.5 ft are shown on Mount Rainier and large areas of the central WA Cascades and also high up in the Three Sisters in Oregon. The lowland snowfall is still almost completely absent from the Washington image similar to 24 hours earlier (see Update #14 above), with the remaining areas of lowland snow still limited to northwest Washington, the San Juan Islands, and along the Strait of Juan de Fuca. There's still a small chance that it might snow anyway in other areas despite model predictions stating that it won't, but temperatures are likely to remain just too warm farther south than that area.
This loop shows how the model predictions for snowfall during the 3-day period through 4am Wednesday have evolved between 10 subsequent runs over the last 5 days, the D(model)/D(t). Very consistent in the overall picture throughout although with minor variations, which shows that the model had locked on to the solution predicting additional storms this weekend by about 5 days ago. The biggest change has been a sharp reduction in snowfall amounts for northern Oregon over the most recent runs, which is primarily due to greater warming down there rather than a large reduction in predicted precip amounts:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014022612///+-st
The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon that morning and then another system on Friday into Saturday and Sunday. Snowfall from that new storm cycle during the 3-day period ending 4am next Saturday is now predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, a fairly significant reduction from 24 hours ago:
It still appears likely that this critically-needed major storm cycle for California will actually occur, but details and timing continue to change substantially on subsequent model runs, as do the total snowfall amounts as seen in the D(model)/D(t) for this period, including 4 runs over the last 2 days:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030112///+-st
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24 Feb 2014 14:04 - 24 Feb 2014 14:14 #220761
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
Update #16: 432 hours (18 days) after initial post, 2-12 ft of snow has already fallen along the coast from Alaska to California,
perhaps up to 14-15 ft or more in spots, with an additional 0.5-1 ft predicted through Tuesday!
Another brief update on the last day of significant snowfall during this storm cycle, as 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict up to an additional 0.5-1 ft of snowfall over the Washington Cascades through Tuesday morning. The lowland snowfall in northwestern Washington over the past 2 days is expected to change over to all rain soon.
As of Monday morning, another 3-15" of new snow has fallen over the past 24 hours from about Whistler south to White Pass (bringing 2-day totals up to 1-2 ft at many sites), with only an inch or two farther south to Mount Hood and Bachelor followed by rain as the snow level rose to 7000 and even 8000 ft, and still sunny skies from southern Oregon into California. There is an amazing contrast and sharp north-south gradient in snow levels this morning, ranging from sea level near Bellingham, to 1000-2000 ft at Stevens and Snoqualmie Passes (assisted by easterly pass flow), to 6000 ft at Mount Rainier and 8000 ft on Mount Hood, due to a weird combo of cold Fraser River outflow, cold easterly pass flow, and warm air being pulled up from the southwest.
The largest new snowfalls were in parts of southwestern BC and the North Cascades with about 1 ft, topped by 15" at Whistler (surprisingly, its largest 24-hour snowfall of the entire storm cycle), 13" at Holden Village (on top of 14" yesterday, bringing its storm total snowfall up to 128", astounding given that it's several miles east of the Cascade Crest), and 10" at Mount Baker Ski Area and Stevens Pass. Large parts of the lowlands of northwest Washington and the San Juan Islands also got up to 6-12" of new snow, as cold air flowing out of the Fraser River valley kept temperatures cool enough for snow. This area of maximum snowfall was once again farther north than the model had predicted, as it had shown 1 ft amounts in the Central Cascades with only a few inches on Mount Baker or southwestern BC, and the large amounts in the lowlands exceeded model predictions too.
Here are the same 3 webcams shown the past 2 days in Updates #14 and #15 above, along I-5 from MP 258 to 246 near Bellingham, still showing snowfall but getting close to changing to rain (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is again expected to intensify midday Monday through the afternoon, and continue into early Tuesday. Snowfall during the next 2 days through 4am Wednesday (which catches all the last bits of this storm cycle) is predicted to be up to 0.5-1 ft over most of the Washington Cascades north of Mount Rainier and central Vancouver Island, with several inches over parts of the mainland of southwestern BC, the Olympics, southern Washington Cascades, and Columbia Gorge:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington:
Maximum snowfall amounts of over 1 ft are still shown on Mount Rainier, but this is looking increasingly doubtful at least at any measurement sites like Paradise since snow levels have risen to 6000 ft. Almost no more snow is expected in the Oregon Cascades due to very high snow levels, except along the Columbia Gorge where easterly flow will keep temps cold enough for snow.
The next storm cycle is still predicted to begin on Wednesday, although the timing has continued to look slightly later than it did a few days ago, with the first system arriving from the southwest into northern California and southern Oregon midday Wednesday through Thursday, with another system on Friday into Saturday and Sunday. Snowfall from that new storm cycle during the 3-day period ending 4pm next Saturday is still predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, similar to 24 hours ago with perhaps a slight increase:
It still appears likely that this critically-needed major storm cycle for California will actually occur, but details and timing continue to change substantially on subsequent model runs, as do the total snowfall amounts as seen in the D(model)/D(t) for this period, including 5 runs over the last 3 days:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030200///+-st
Now on to analyzing, calculating, and adding up the snowfall totals for the entire storm cycle at over 200 measurement sites from Alaska to the southern Sierra Nevada . . .
perhaps up to 14-15 ft or more in spots, with an additional 0.5-1 ft predicted through Tuesday!
Another brief update on the last day of significant snowfall during this storm cycle, as 2 more subsequent runs of the UW WRF-GFS model at 12-hour intervals continue to predict up to an additional 0.5-1 ft of snowfall over the Washington Cascades through Tuesday morning. The lowland snowfall in northwestern Washington over the past 2 days is expected to change over to all rain soon.
As of Monday morning, another 3-15" of new snow has fallen over the past 24 hours from about Whistler south to White Pass (bringing 2-day totals up to 1-2 ft at many sites), with only an inch or two farther south to Mount Hood and Bachelor followed by rain as the snow level rose to 7000 and even 8000 ft, and still sunny skies from southern Oregon into California. There is an amazing contrast and sharp north-south gradient in snow levels this morning, ranging from sea level near Bellingham, to 1000-2000 ft at Stevens and Snoqualmie Passes (assisted by easterly pass flow), to 6000 ft at Mount Rainier and 8000 ft on Mount Hood, due to a weird combo of cold Fraser River outflow, cold easterly pass flow, and warm air being pulled up from the southwest.
The largest new snowfalls were in parts of southwestern BC and the North Cascades with about 1 ft, topped by 15" at Whistler (surprisingly, its largest 24-hour snowfall of the entire storm cycle), 13" at Holden Village (on top of 14" yesterday, bringing its storm total snowfall up to 128", astounding given that it's several miles east of the Cascade Crest), and 10" at Mount Baker Ski Area and Stevens Pass. Large parts of the lowlands of northwest Washington and the San Juan Islands also got up to 6-12" of new snow, as cold air flowing out of the Fraser River valley kept temperatures cool enough for snow. This area of maximum snowfall was once again farther north than the model had predicted, as it had shown 1 ft amounts in the Central Cascades with only a few inches on Mount Baker or southwestern BC, and the large amounts in the lowlands exceeded model predictions too.
Here are the same 3 webcams shown the past 2 days in Updates #14 and #15 above, along I-5 from MP 258 to 246 near Bellingham, still showing snowfall but getting close to changing to rain (elevations of these webcams are about 200 ft, 200 ft, and 560 ft at I-5 at Lake Samish Park and Ride in the last image):
Snowfall in the Washington Cascades is again expected to intensify midday Monday through the afternoon, and continue into early Tuesday. Snowfall during the next 2 days through 4am Wednesday (which catches all the last bits of this storm cycle) is predicted to be up to 0.5-1 ft over most of the Washington Cascades north of Mount Rainier and central Vancouver Island, with several inches over parts of the mainland of southwestern BC, the Olympics, southern Washington Cascades, and Columbia Gorge:
Higher resolution version of that, showing the Pacific Northwest and also zoomed in on Washington:
Maximum snowfall amounts of over 1 ft are still shown on Mount Rainier, but this is looking increasingly doubtful at least at any measurement sites like Paradise since snow levels have risen to 6000 ft. Almost no more snow is expected in the Oregon Cascades due to very high snow levels, except along the Columbia Gorge where easterly flow will keep temps cold enough for snow.
The next storm cycle is still predicted to begin on Wednesday, although the timing has continued to look slightly later than it did a few days ago, with the first system arriving from the southwest into northern California and southern Oregon midday Wednesday through Thursday, with another system on Friday into Saturday and Sunday. Snowfall from that new storm cycle during the 3-day period ending 4pm next Saturday is still predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, similar to 24 hours ago with perhaps a slight increase:
It still appears likely that this critically-needed major storm cycle for California will actually occur, but details and timing continue to change substantially on subsequent model runs, as do the total snowfall amounts as seen in the D(model)/D(t) for this period, including 5 runs over the last 3 days:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030200///+-st
Now on to analyzing, calculating, and adding up the snowfall totals for the entire storm cycle at over 200 measurement sites from Alaska to the southern Sierra Nevada . . .
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25 Feb 2014 12:26 - 25 Feb 2014 13:35 #220807
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
Sunrise after the storm (again!):
Well, it's finally over. The storm cycle that kept going and going and going, is coming to an end at long last on Tuesday with the last remnants of the final storm system fading out along the Washington-Oregon border. As of Tuesday morning, another 2-7" of new snow has fallen over the past 24 hours from about Whistler south to White Pass, along with rain at many locations away from the passes without the benefit of easterly flow to keep temperatures down. There was rain up to 5000-6000 ft at Mount Baker, Hurricane Ridge, Crystal Mountain, Mount Rainier Paradise, etc., plus some freezing rain near the passes too. This is the Pacific Northwest after all!
Skies again cleared by sunrise at many mountain locations north and south of the Washington-Oregon border region in southwestern BC, northern Washington, and southern Oregon (and remained clear in California):
[size=small]Sunrise from atop Whistler Mountain on the volcanic peaks of Mount Garibaldi (left) and Black Tusk (center) plus Mount Tantalus (right).[/size]
[size=small]Sunrise on Mount Garibaldi seen from the opposite direction near Squamish .[/size]
[size=small]Sunrise glow behind Mount Baker and Twin Sisters Mountain, as seen on the visibility camera from Ferndale at 350 ft with snow on the rooftops.[/size]
[size=small]Cool clouds above and below in the valley from Hurricane Ridge .[/size]
[size=small]Clear skies on Glacier Peak, as seen from my deck in Seattle, 10:00am February 25.[/size]
[size=small]Mount Rainier producing a fallstreak hole in an altocumulus cloud deck advancing from the southwest, as seen from my deck in Seattle, 9:00am February 25.[/size]
This is the second time I can recall seeing Mount Rainier produce a fallstreak hole in an altocumulus cloud deck, see this thread from 2 years ago ( Unusual lenticular "hole" cloud above Mt Rainier ). This time it is a very obvious and classic-looking fallstreak hole , complete with the typical wispy cloud debris streaming downward from the hole. Here is a wider-angle view taken 15 minutes later, showing the hole having moved farther to the NE of Rainier:
[size=small]Mount Rainier producing a fallstreak hole in an altocumulus cloud deck advancing from the southwest, as seen from my deck in Seattle, 9:15am February 25.[/size]
One of the UW Atmospheric Sciences webcams has a view of Rainier, and this loop of images every 5 minutes from 8-10am on February 25 shows the formation and motion of the fallstreak hole from 8:45am over the next hour (ignore the times listed at top which are 8 hours off, the correct times are printed on the images). You can also view the same loop with a 1 minute interval, loop of images every minute from 8-10am on February 25 .
[size=small]The Mountain was only out for a short time early in the morning and again just after noon from the other side at Paradise .[/size]
[size=small]Sunrise glow just reaching the summits of South Sister, Middle Sister, and North Sister (left to right) as seen from Mount Bachelor .[/size]
[size=small]Sunrise at Crater Lake .[/size]
[size=small]Mount Shasta briefly capped by a short stack of thin lenticular clouds on Tuesday morning, as seen on the SnowCrest webcam .[/size]
Update on the next storm cycle:
Still on track and now nearly certain to occur! The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon midday Wednesday through Thursday, with another system on Friday into Saturday. Snowfall from that new storm cycle during the 3-day period ending 4pm Saturday is still predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, similar to 24 hours ago with perhaps a slight increase in amounts and also with some snowfall extending farther north into Washington:
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Saturday have evolved between 7 subsequent runs over the last 4 days, the D(model)/D(t). Fairly consistent in the overall picture for California throughout these runs, although with variations in details and timing and total snowfall amounts:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030200///+-st
There is a major lull on Sunday, then the next system is predicted for Monday-Tuesday into Oregon and southern Washington. This is the (shocking!) prediction for snowfall during the 24-hour period ending 4pm next Tuesday:
Yes, it's showing a large area of lowland snowfall throughout southwestern Washington and northwestern Oregon, with amounts exceeding 1 ft over a good portion of that. This certainly bears watching, but is a highly improbable prediction given climatology and is still 6-7 days out, right at the limit of accurate numerical weather prediction. More than likely, this lowland snowfall will vanish or be greatly reduced in later model runs. We shall see!
Well, it's finally over. The storm cycle that kept going and going and going, is coming to an end at long last on Tuesday with the last remnants of the final storm system fading out along the Washington-Oregon border. As of Tuesday morning, another 2-7" of new snow has fallen over the past 24 hours from about Whistler south to White Pass, along with rain at many locations away from the passes without the benefit of easterly flow to keep temperatures down. There was rain up to 5000-6000 ft at Mount Baker, Hurricane Ridge, Crystal Mountain, Mount Rainier Paradise, etc., plus some freezing rain near the passes too. This is the Pacific Northwest after all!
Skies again cleared by sunrise at many mountain locations north and south of the Washington-Oregon border region in southwestern BC, northern Washington, and southern Oregon (and remained clear in California):
[size=small]Sunrise from atop Whistler Mountain on the volcanic peaks of Mount Garibaldi (left) and Black Tusk (center) plus Mount Tantalus (right).[/size]
[size=small]Sunrise on Mount Garibaldi seen from the opposite direction near Squamish .[/size]
[size=small]Sunrise glow behind Mount Baker and Twin Sisters Mountain, as seen on the visibility camera from Ferndale at 350 ft with snow on the rooftops.[/size]
[size=small]Cool clouds above and below in the valley from Hurricane Ridge .[/size]
[size=small]Clear skies on Glacier Peak, as seen from my deck in Seattle, 10:00am February 25.[/size]
[size=small]Mount Rainier producing a fallstreak hole in an altocumulus cloud deck advancing from the southwest, as seen from my deck in Seattle, 9:00am February 25.[/size]
This is the second time I can recall seeing Mount Rainier produce a fallstreak hole in an altocumulus cloud deck, see this thread from 2 years ago ( Unusual lenticular "hole" cloud above Mt Rainier ). This time it is a very obvious and classic-looking fallstreak hole , complete with the typical wispy cloud debris streaming downward from the hole. Here is a wider-angle view taken 15 minutes later, showing the hole having moved farther to the NE of Rainier:
[size=small]Mount Rainier producing a fallstreak hole in an altocumulus cloud deck advancing from the southwest, as seen from my deck in Seattle, 9:15am February 25.[/size]
One of the UW Atmospheric Sciences webcams has a view of Rainier, and this loop of images every 5 minutes from 8-10am on February 25 shows the formation and motion of the fallstreak hole from 8:45am over the next hour (ignore the times listed at top which are 8 hours off, the correct times are printed on the images). You can also view the same loop with a 1 minute interval, loop of images every minute from 8-10am on February 25 .
[size=small]The Mountain was only out for a short time early in the morning and again just after noon from the other side at Paradise .[/size]
[size=small]Sunrise glow just reaching the summits of South Sister, Middle Sister, and North Sister (left to right) as seen from Mount Bachelor .[/size]
[size=small]Sunrise at Crater Lake .[/size]
[size=small]Mount Shasta briefly capped by a short stack of thin lenticular clouds on Tuesday morning, as seen on the SnowCrest webcam .[/size]
Update on the next storm cycle:
Still on track and now nearly certain to occur! The next storm cycle is still predicted to begin on Wednesday, with the first system arriving from the southwest into northern California and southern Oregon midday Wednesday through Thursday, with another system on Friday into Saturday. Snowfall from that new storm cycle during the 3-day period ending 4pm Saturday is still predicted to be up to 2-3 ft at higher elevations of the California Cascades, Trinity Alps, and Sierra Nevada, similar to 24 hours ago with perhaps a slight increase in amounts and also with some snowfall extending farther north into Washington:
This loop shows how the model predictions for snowfall during the 3-day period through 4pm Saturday have evolved between 7 subsequent runs over the last 4 days, the D(model)/D(t). Fairly consistent in the overall picture for California throughout these runs, although with variations in details and timing and total snowfall amounts:
www.atmos.washington.edu/~ovens/wxloop.c...2+v2014030200///+-st
There is a major lull on Sunday, then the next system is predicted for Monday-Tuesday into Oregon and southern Washington. This is the (shocking!) prediction for snowfall during the 24-hour period ending 4pm next Tuesday:
Yes, it's showing a large area of lowland snowfall throughout southwestern Washington and northwestern Oregon, with amounts exceeding 1 ft over a good portion of that. This certainly bears watching, but is a highly improbable prediction given climatology and is still 6-7 days out, right at the limit of accurate numerical weather prediction. More than likely, this lowland snowfall will vanish or be greatly reduced in later model runs. We shall see!
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25 Feb 2014 16:29 #220816
by andybrnr
Replied by andybrnr on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
Even in the UW Atmos Sci Dept., we don't have access to the ECMWF output, and if we did, the terms under which we got it would prevent it from being shared. Again, at 7 days out, I'd really suggest relying on ensemble output as opposed to a single deterministic run... as Amar suggests, at 7 days climatology is about as skillful a predictor (depending on the exact model, climatology may be a MORE skillful predictor).
So, back to my personal favorite tool for prognostications beyond 5 days, NAEFS. It combines the outputs from the Canadian and American ensemble systems, for a total of 42 different possible realizations of the atmosphere out to two weeks. For point forecasts at individual cities, this data is statistically corrected to produce calibrated, unbiased probability distributions for a number of variables. To appreciate the general pattern, viewing contour maps of the model mean and standard deviation can provide some information, but at two weeks this looks pretty messy... you can also look at all the individual ensemble members, but that gets overwhelming. Thus I think using the Seattle forecast as a proxy for the downstream conditions in the Central Cascades is a good first approach... it gives a sense of the range of possible outcomes, the degree of uncertainty, and as a given time gets closer, the higher resolution deterministic runs become somewhat more useful.
So, let's look at the two most recent NAEFS EPSgrams for Seattle:
2-25-14 00Z
2-25-14 12Z
Be careful when comparing the vertical scales between runs, as they adapt to max values. There are some substantial differences between these runs even in the near term; the chances of precip before the weekend have come up a bit. Both runs show we're likely to get some cold air down towards the beginning of next week, and it may in fact include a chance for lowland snow... but the range of possible outcomes is quite big, and the bars for the 25-75% are substantial. Anyhow, it is clear there is substantial uncertainty in the next week, with a few days of colder conditions followed by a trend to warmer conditions in the longer term (8-14 days).
So, back to my personal favorite tool for prognostications beyond 5 days, NAEFS. It combines the outputs from the Canadian and American ensemble systems, for a total of 42 different possible realizations of the atmosphere out to two weeks. For point forecasts at individual cities, this data is statistically corrected to produce calibrated, unbiased probability distributions for a number of variables. To appreciate the general pattern, viewing contour maps of the model mean and standard deviation can provide some information, but at two weeks this looks pretty messy... you can also look at all the individual ensemble members, but that gets overwhelming. Thus I think using the Seattle forecast as a proxy for the downstream conditions in the Central Cascades is a good first approach... it gives a sense of the range of possible outcomes, the degree of uncertainty, and as a given time gets closer, the higher resolution deterministic runs become somewhat more useful.
So, let's look at the two most recent NAEFS EPSgrams for Seattle:
2-25-14 00Z
2-25-14 12Z
Be careful when comparing the vertical scales between runs, as they adapt to max values. There are some substantial differences between these runs even in the near term; the chances of precip before the weekend have come up a bit. Both runs show we're likely to get some cold air down towards the beginning of next week, and it may in fact include a chance for lowland snow... but the range of possible outcomes is quite big, and the bars for the 25-75% are substantial. Anyhow, it is clear there is substantial uncertainty in the next week, with a few days of colder conditions followed by a trend to warmer conditions in the longer term (8-14 days).
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10 Mar 2014 22:23 #221184
by Amar Andalkar
Replied by Amar Andalkar on topic Re: HUGE storm cycle brings 4-14 ft snow Feb6-25,2014!
[size=small](Split from previous post due to TAY's 20,000 character limit per post.)[/size]
California has its own state-run snow telemetry network ( California Cooperative Snow Surveys ), so data from most of the state except a few areas near the Nevada border is not part of the SNOTEL network, and is not plotted on those maps. Here is what the California snowpack (snow water content) looks like as of March 5 (note that unlike the SNOTEL maps above, this map shows % of April 1 average, not % of current normal values):
And how it has evolved during this season compared to the last 3 years and to the historically snowiest (1982-83) and driest (1976-77) years:
The first week of March looks to be very wet and stormy over almost the entire region covered above (except the southern Sierra Nevada), with a new storm cycle bringing 4-8 ft of snow (February 26-March 8, 2014) (perhaps more at high elevations), and that stormy pattern may continue into the second week of the month too. As of March 4 when this data was tabulated and posted, snowdepths have already increased by about 10-40" at many of these sites since March 1. By the time the March 15 numbers come out, the snowpack may be above normal in southwestern BC, Washington, and northern Oregon, and hopefully quite a bit closer to normal in southern Oregon and northern California.
The British Columbia River Forecast Centre finally released its March 1st snow survey bulletin today on March 10 (normally it's released around the 7th of the month, so it's really only 1 business day late). For the sake of completeness, the March 1 table above in the previous post has been expanded to include several additional sites in southwestern BC, and here is a 2-image GIF showing the change in snowpack (snow water equivalent) from February 1 to March 1 in BC:
This shows a large increase throughout southwestern BC, but the largest increases of all were on Vancouver Island and the BC Cascades (the Skagit, Similkameen, and SE part of the Lower Fraser basins). Despite those large increases, the snowpack is still well below normal in all of southwestern BC except the BC Cascades. The snowpack actually decreased as a percent of normal during February throughout most of the rest of BC, except southeastern BC which had modest increases, but the rest of the province remains near-normal for snowpack.
The current storm cycle reached this region on March 1, and has delivered very heavy precip and snowfall to southwestern BC through March 9, with snow levels generally not rising above 5000 ft during either of the two atmospheric river events (unlike areas to the south where they rose above 7000-9000 ft). So the snowpack in southwestern BC has already improved significantly from the March 1 values shown here.
California has its own state-run snow telemetry network ( California Cooperative Snow Surveys ), so data from most of the state except a few areas near the Nevada border is not part of the SNOTEL network, and is not plotted on those maps. Here is what the California snowpack (snow water content) looks like as of March 5 (note that unlike the SNOTEL maps above, this map shows % of April 1 average, not % of current normal values):
And how it has evolved during this season compared to the last 3 years and to the historically snowiest (1982-83) and driest (1976-77) years:
The first week of March looks to be very wet and stormy over almost the entire region covered above (except the southern Sierra Nevada), with a new storm cycle bringing 4-8 ft of snow (February 26-March 8, 2014) (perhaps more at high elevations), and that stormy pattern may continue into the second week of the month too. As of March 4 when this data was tabulated and posted, snowdepths have already increased by about 10-40" at many of these sites since March 1. By the time the March 15 numbers come out, the snowpack may be above normal in southwestern BC, Washington, and northern Oregon, and hopefully quite a bit closer to normal in southern Oregon and northern California.
The British Columbia River Forecast Centre finally released its March 1st snow survey bulletin today on March 10 (normally it's released around the 7th of the month, so it's really only 1 business day late). For the sake of completeness, the March 1 table above in the previous post has been expanded to include several additional sites in southwestern BC, and here is a 2-image GIF showing the change in snowpack (snow water equivalent) from February 1 to March 1 in BC:
This shows a large increase throughout southwestern BC, but the largest increases of all were on Vancouver Island and the BC Cascades (the Skagit, Similkameen, and SE part of the Lower Fraser basins). Despite those large increases, the snowpack is still well below normal in all of southwestern BC except the BC Cascades. The snowpack actually decreased as a percent of normal during February throughout most of the rest of BC, except southeastern BC which had modest increases, but the rest of the province remains near-normal for snowpack.
The current storm cycle reached this region on March 1, and has delivered very heavy precip and snowfall to southwestern BC through March 9, with snow levels generally not rising above 5000 ft during either of the two atmospheric river events (unlike areas to the south where they rose above 7000-9000 ft). So the snowpack in southwestern BC has already improved significantly from the March 1 values shown here.
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