"Acid" rain at Snoqualmie

6.2" rain at Alpental since 3pm yesterday and all near 40F. Damn that is impressive in a not so very nice way. Thats going to hurt the snowpack and I'm sure there will be some holes opening. Hope we finally get the cold bang La Nina is meant to deliver.

You mean "holes enlarging?" Seemed we hadn't quite gotten the holes filled in yet, at least out in the backcountry.

Cools off mid-week, but then warms up into the weekend per current forecast. Hopefully they're just as wrong in this direction as they were in the other direction a bit over a week ago...

It looks like the now 7+" of rain has not hurt the snow depth at all, it's only gone from 68" to 65" --  as usual, rain (even at 40 °F) is almost entirely incapable of melting snow (see this thread from 2 years ago for an explanation of why: 30" of snow lost in 21hrs @ Snoqualmie? ).

The well-consolidated snowpack prior to last night's downpour (due to the last few days of rain) will also limit the formation of severe rain runnels and large holes. Yes, of course there will be rain runnels, and maybe even new holes near creeks after this, but they won't be as bad as they would be if the snowpack were less consolidated when the deluge began.

Anyway, it's a stunning amount of rain, especially the several hours with over 0.4" of rain per hour:

Northwest Weather and Avalanche Center
Alpental Ski Area, Washington

Wind sensors unheated and may rime

MM/DD  Hour  Temp  Temp  Temp    RH    RH  Wind  Wind  Wind  Hour Total  24Hr Total
         PST     F     F     F     %     %   Avg   Max  Dir. Prec. Prec.  Snow  Snow
             5400' 4300' 3120' 3120' 5400' 5530' 5530' 5530' 3120' 3120' 3120' 3120'

---

  1 15  1400    33    37    38    88    89    12    20   233     0     0     0    68
  1 15  1500    31    35    36    96    99    12    21   169   .01   .01     0    68
  1 15  1600    31    33    36    98    99    18    24   138   .14   .15     0    68
  1 15  1700    30    33    36    99   100    19    27   143    .1   .25     0    68
  1 15  1800    30    32    35   100   100    23    31   148   .16   .41     0    67
  1 15  1900    30    32    34   100   100    15    23   147   .24   .65     0    68
  1 15  2000    31    32    34   100   100    11    17   157   .34   .99     0    68
  1 15  2100    33    32    34   100   100    18    34   225   .28  1.27     0    68
  1 15  2200    35    34    34   100   100    24    46   237   .36  1.63     0    68
  1 15  2300    36    37    34   100    99    23    50   243   .27   1.9     0    67
  1 16     0    36    37    36   100    99    26    50   243   .68  2.58     0    66
  1 16   100    36    38    36   100    99    21    43   233   .23  2.81     0    67
  1 16   200    37    39    37   100    99    27    69   230   .28  3.09     0    67
  1 16   300    38    40    38   100    99    32    57   242   .32  3.41     0    67
  1 16   400    37    39    38   100   100    35    63   243   .33  3.74     0    66
  1 16   500    37    39    38   100   100    29    48   244   .17  3.91     0    66
  1 16   600    37    39    38   100    99    32    52   247   .58  4.49     0    66
  1 16   700    38    39    37   100   100    33    58   243   .44  4.93     0    66
  1 16   800    37    41    38   100   100    36    61   244   .49  5.42     0    65
  1 16   900    37    40    39   100   100    32    57   241   .48   5.9     1    66
  1 16  1000    37    40    40   100   100    26    49   236    .3   6.2     0    65
  1 16  1100    39    40    38   100   100    34    61   246   .34  6.54     1    65
  1 16  1200    38    40    41    99    99    31    61   243   .29  6.83     0    64
  1 16  1300    38    40    41   100   100    31    53   241   .18  7.01     0    65


And even more rain is falling at Mount Hood:

Northwest Weather and Avalanche Center
Timberline Lodge, Oregon

MM/DD  Hour  Temp    RH  Wind  Wind  Wind  Wind  Hour Total 24 Hr Total
         PST     F     %   Min   Avg   Max   Dir Prec. Prec.  Snow  Snow
             6000' 6000' 6000' 6000' 6000' 6000' 6000' 6000' 6000' 6000'

---

  1 15  1400    38   100     0     6    13   287   .12   .12    31   101
  1 15  1500    38   100     0     6    13   282   .18    .3    31   100
  1 15  1600    39   100     0     6    14   288   .22   .52     0   100
  1 15  1700    39   100     4    10    20   297   .22   .74     0   100
  1 15  1800    38   100     5    10    17   297   .21   .95     0    99
  1 15  1900    38   100     3     9    23   290   .21  1.16     0    99
  1 15  2000    38   100     4     9    18   291   .25  1.41     0    99
  1 15  2100    37   100     4     9    18   293   .21  1.62     0    99
  1 15  2200    37   100     4     9    18   300   .15  1.77     0    99
  1 15  2300    37   100     4     8    16   299   .21  1.98     0    98
  1 16     0    37   100     4     8    16   297   .31  2.29     0    98
  1 16   100    38   100     4     8    18   294   .26  2.55     0    98
  1 16   200    38   100     4     9    18   300   .27  2.82     0    97
  1 16   300    40   100     4     8    14   293   .14  2.96    -0    97
  1 16   400    41   100     3     8    17   288   .38  3.34     0    97
  1 16   500    39   100     4     9    23   295   .48  3.82     0    97
  1 16   600    38   100     4     8    14   288   .45  4.27     0    96
  1 16   700    39   100     4     8    15   284   .44  4.71     0    95
  1 16   800    40   100     4     9    19   286   .62  5.33     0    95
  1 16   900    40   100     4     9    17   292   .57   5.9     0    95
  1 16  1000    40   100     4    10    20   290   .61  6.51     0    95
  1 16  1100    39   100     4    10    19   289   .55  7.06     0    93
  1 16  1200    40   100     5    11    26   285   .38  7.44     0    93
  1 16  1300    40   100     5    12    23   286   .41  7.85     0    91

Amar, you're like my little ray of sunshine.

I knew Amar would come back with this!  I remember reading that the misty warm rain is the worst from a great physics of snowmelt thread from a few years back. Took the kids to Snoq falls to see the twigs (read large trees) going over. Always fun to watch.

If I could isolate three- 2ft high x 1ft wide and 1ft deep columns of snow.
One of them is packed non-cohesive low density powder at lets say temp of 22 degrees.
The other granular isothermic packed snow 34 degrees.
The last one is cohesive 32 degree high density snow.

If it was possible to equally sprinkle 3 inches of colored water over a 24hr period on the top of each column, which test column would have the most measurable percolation through the snowpack.
It would be interesting to see the results.
I think that the Isothermic would be the fastest, given the spacing the rounding of the snow.
with the least perk being the low density snow.

I'm just basing my science off the snow that falls on the roof of my garage and the rains that follow it. The samples I see tend to lead to very little saturation of liquid into snowpack that is low density and cold, but much quicker into wetter snows.

Any real science out here to verify those thoughts?

Multi-State Flood warning:
seattletimes.nwsource.com/html/localnews...s2ndldwritethru.html

Superstorm warning: (getting you ready for the next stage)
seattletimes.nwsource.com/html/nationwor...9_califstorms16.html

Evacuating towns:
seattletimes.nwsource.com/html/theweathe...o_pending_flood.html


JANUARY 16th, 2011, Sunday.
Alpental...closed
Silver Fir...closed
Stevens...partly closed
Crystal...SERIOUS RAIN
Timberline...partly closed due to conditions
and MUCH MUCH MORE!

What is it going to take for you guys to realize you-know-what?

10, 9, 8, 7, 6, 5, 4, 3, 2... ...fini

BillyTheMountain

Snow is soft but easily transforms the hardest material. - Schluctism

I knew Amar would come back with this!  I remember reading that the misty warm rain is the worst from a great physics of snowmelt thread from a few years back.  Took the kids to Snoq falls to see the twigs (read large trees) going over.  Always fun to watch.

Good call. Almost went up there this weekend to be a big kid and watch the same. It is always an impressive sight. I stayed there through a big warm rain-after-snow event a bunch of years back, and was sleeping toward the falls end of Salish Lodge. Which was positively vibrating. It was weird and cool. No need for a white noise machine to sleep - that's for sure!

Yeah, I'm not bummed that we'll get some hard core consolidation of the snowpack. It would of course be awesome if the rain events happened early in the workweek, and then it would cool off and dump new snow in time for a safe, fun weekend.

OH dark and black of soul and lord of the underworld... ...I would GLADLY give my soul for 50 inches of nice powder SNOW, and NO lift line.
Just for one day Lord of Reptiles and the Coven of "Nickolas" Beelzebub and the mathematics of our lot 3 fire-circle, I promise you, my own deep soul and transience corporate body.
I now burn the straw to cleanse the sky for my BROTHERS to make the snow and save the day from the evil evil WARM weather.
(burns many clouds of smoke in honor of our Crystal mountain brothers and sisters to help make it snow)
Has received the happy happy thoughts of peace and love,
BillyTheMountain

Snow will lay around but it will not lie below. - Schluctism

OH dark and black of soul and lord of the underworld... ...I would GLADLY give my soul for 50 inches of nice powder SNOW, and NO lift line.
Just for one day Lord of Reptiles and the Coven of "Nickolas" Beelzebub and the mathematics of our lot 3 fire-circle, I promise you, my own deep soul and transience corporate body.
I now burn the straw to cleanse the sky for my BROTHERS to make the snow and save the day from the evil evil WARM weather.
(burns many clouds of smoke in honor of our Crystal mountain brothers and sisters to help make it snow)
Has received the happy happy thoughts of peace and love,
BillyTheMountain

Snow will lay around but it will not lie below. - Schluctism



B

wow.... been soaking up the "acid" rain??? wow.

Did you see the new forecast? Don't knock it, it seems to be working.

Reminds me of the classic "don't hit me me with them negative waves" lines from Kelly's Heroes.

With that in mind, I'll try to remember that the forecast for 6-7 days out tends to be about as accurate as a roll of the dice. 

By my count of the telemetry Alpental base received about 17.6 inches of rain in the 6 days to January 17. Average, about 3 inches per day. That used to be a good SNOW total!

Reminds me of the classic "don't hit me me with them negative waves" lines from Kelly's Heroes.

Woof!