Windiest day ever at Mt Baker NWAC site: 117 mph!!

Windiest day ever recorded at Mount Baker Ski Area NWAC site: 117 mph maximum!! December 20, 2018
  (and 5 consecutive hours with gusts over 100 mph!)

The moderately-strong windstorm which passed through western Washington earlier today (Thursday, December 20) was quite exceptional in at least one important location: the NWAC telemetry site atop 5020 ft Panorama Dome at Mount Baker Ski Area recorded its strongest winds since it was installed almost 11 years ago. The maximum gust of 117 mph in the hour before noon on December 20 was only 1 mph greater than the previous maximum gust of 116 mph on March 3, 2011, but the duration of the high winds was what really set this day apart as the windiest day ever recorded at this telemetry site. Wind gusts exceeded 100 mph for 5 consecutive hours between 10am and 3pm, versus a grand total of only 9 such hours with 100 mph gusts previously in the entire 11-year period of record!





The Mount Baker Ski Area telemetry site is typically not extremely windy, especially when compared to the most windy NWAC telemetry sites (10100 ft Camp Muir on Mount Rainier, 6730 ft top of Mission Ridge, 6830 ft top of Crystal Mountain, 5970 ft Pigtail Peak at White Pass, 7000 ft top of Magic Mile and 7300 ft top of Cascade Express on Mount Hood). Those other sites regularly exceed 100 mph during strong storm systems, often several times in a single season, with Muir and Mission Ridge occasionally reaching the 130 to 150+ mph range. But the Mount Baker Ski Area site typically does not even hit 90 mph during many years as seen in the table below, with winds failing to reach 90 mph in 6 of the 12 seasons (including partial seasons in 2008 and so far this fall) and wind gusts over 100 mph in only 5 of those 12 seasons:


2018-19:  117 mph max, 5 consecutive hours over 100 mph gusts, 20Dec2018 
2017-18:   97 mph max
2016-17:   87 mph max
2015-16:  109 mph max, 2 hours over 100 mph gusts in 3-hour period, 10Mar2016
2014-15:  105 mph max, 2 hours over 100 mph gusts (separate days)
2013-14:   80 mph max
2012-13:   82 mph max
2011-12:   89 mph max
2010-11:  116 mph max, 2 consecutive hours over 100 mph gusts, 03Mar2011
2009-10:  103 mph max, 3 hours over 100 mph gusts in 5-hour period, 05Nov2009
2008-09:   89 mph max
2007-08:   68 mph max, wind data begins on 09Jan2008


So today's event was really quite extraordinary compared to anything else in the period of record at this telemetry site! The highest wind gust recorded at any other NWAC site during this windstorm was 107 mph atop Pigtail Peak at White Pass in the noon-1pm hour, with 94 mph at the top of Magic Mile on Mount Hood, 91 mph at the top of Crystal Mountain, and 88 mph at the top of Mission Ridge. (After this was originally posted, winds atop Mission Ridge spiked up to 98 mph and then 119 mph during the 10-11pm hours, by which time the high winds had long subsided at Baker and most other NWAC sites.)

But this high-wind event was almost missed by the instruments at the Mount Baker Ski Area telemetry site, as the unheated wind gages had been rimed up and frozen solid for almost 2 days until temperatures warmed above freezing in the early AM hours of December 20, just a few hours before the windstorm passed through. It's also possible that other high-wind events could have been missed in previous years when the wind gage was rimed, although this is not a very frequent occurrence at the Baker site compared to other more remote NWAC sites with unheated wind gages. In particular the Camp Muir site, where the wind gages often spend days, weeks, or even months rimed up and inoperative during every fall-winter-spring season, as it was during this windstorm (plus a telemetry outage there too).

As for the Mount Baker Ski Area itself, staff had already decided the day before that they would be closed all day on Thursday due to the expected winds, a very good decision in light of what actually did occur!

What was the damage around Baker like?! That kind of wind could really tear the place up badly!

For a detailed analysis of the windstorm which produced the record winds at the Mount Baker NWAC site, see this lengthy blog post by Wolf Read:

The Solstice Eve Windstorm of 2018
coquitlamwx.wordpress.com/2018/12/22/the...e-windstorm-of-2018/
(the article is still in progress and not completed yet as of 28Dec2018)

One primary takeaway from the article is that this was roughly a "once-a-decade level windstorm" for the region near Abbotsford, BC, which is the closest airport with detailed climate records to Mount Baker Ski Area, located 33 miles WNW of it (for comparison, Bellingham Airport is about 39 miles west). This once-a-decade level roughly matches what is seen in the historical wind data presented above from the Mount Baker NWAC site too. Read's analysis is primarily concerned with windstorm effects on coastal sites and cities, not up in the mountains, so there is no mention of the record winds at Baker in the current version of the article.

Note that Wolf Read is the researcher and author of the comprehensive Storm King site, which covers "The Climatology and Meteorology of Windstorms That Affect the Cascadia Region of North America, Including the US. Pacific Northwest And Southwest British Columbia, Canada":
www.climate.washington.edu/stormking/

What was the damage around Baker like?!  That kind of wind could really tear the place up badly!

Didn't actually see any reports of significant damage at the ski area, at least not posted on their website over the next couple days. In general, ski lifts, lift towers, and their upper terminals are designed to easily withstand winds well in excess of 100 mph, so damage to those structures would be unlikely during this event.