Thompson Pass is no stranger to epic dumps sitting in the heart of the Chugatch mountains receiving an average of over 552 inches per year. It sits at an altitude of 2,805 feet sitting just outside Valdez Alaska. Its the only road out of the City, home to approximately 3900 in population. Valdez is know as the snowiest City in the United States averaging an incredible 300 inches per season.
Image: Valdez Alaska Wednesday – Photo: Department of Transportation
Imagine a dream of waking up to 52 inches of POW in just 24 hours! In fact according to the snow tel (Automated gauges) that sit 2,000 feet above pass level 83 inches fell in 3 days and 52 fell in the final 24 hours ending Wednesday. At Pass level (2678 feet) they saw 15 inches in just 90 minutes! According to National Weather Service Forecaster Andy Dixon “its possible even higher amounts fell due to the compaction of the snow on the weather stakes” When I asked Dixon if 15 inches in 90 minutes set any records, he stated “Its pretty darn close but its likely some spots in the Great Lakes have reaped higher hourly totals with lake effect snow”
I looked back at snowfall records and found 12 inches in 1 hour in Copenhagen New York set in 1966, and 17.5 inches in 2 hours in Oswego New York (1972). According to data from Weather Underground the world record for 24 hour snowfall is 75.8 inches in April of 1921 in Silver Lake Colorado (How sweet would that be right now). Silver Lake is located in the front range foothills near Denver.
Some measurements taken at the pass level by the Alaska Department of Highways coming in slightly less than what we saw on the snow gauges at 4600 feet. At pass level, manual measurements of 43 inches was recorded in 24 hours of which 16 fell in the final 12 hours ending Wednesday. That puts my deepest day at Squaw a few years ago to shame at 24-32 inches on the 7AM snow report.
Image: Thompson Pass Wednesday- Department of transportation
An Avalanche occurred at 3:30 AM Wednesday on Thompson Pass measuring 20 feet deep and 200 feet long according the transportation department. Roads remained closed until Thursday evening stranding folks in the City of Valdez
Image: Thompson Pass avalanche per the web cam
I asked meteorologist Andy Dixon what factors led up to this epic event. Dixon stated “The blocking high pressure on the west coast is forcing significant pacific moisture into the northern Latitudes.” “Moisture that normally runs east is being forced north.”
Other factors that that contributed to the intense snowfall was an Atmospheric River event that Dixon defined as copious moisture in a long narrow band that is aimed at the Prince William Sound. That moisture funneled directly into the complex terrain at Thompson Pass. I asked what wind direction favors Thompson Pass and he replied “South to Southeast” which is exactly what happened.
Alyeska Resort opened today with 12 inches of new snow at the summit. The epic event over the Valdez Region brought much less new snow to this area just 100 miles west. Complex terrain often will bring wide differences of snow between the different mountain ranges similar to what we would see in the Rockies with wind directions and the aspect of the ski areas playing a major role in receives the deepest amounts.
I called up to Valdez Heli Ski Guides today looking for updates. They plan on opening in February. The Caretaker was apparently out shoveling near the pass but rain is being reported in town. In looking at the latest snow telemetry it appears another 10 inches has fallen since 4PM yesterday (As of 9AM this morning) at Thompson Pass adding to the epic amounts this week.
EXTENDED FORECAST High pressure is expected to remain over the West until at least December 16th. This may keep certain areas of Alaska in a wet pattern while the west coast stays dry. Temperatures will be on the warm side.
Image: High pressure ridge over the west and low pressure in the east (Time stamp December 15th)
The east coast will be active in the short term with moderate snow for southern New England this weekend. A decent event for most of New England may happen mid next week. The current storm track favors coastal New England. It’s likely Boston sees 4-9 inches this weekend with the mountains seeing less. The mid week storm may land 4-9 inches over much of New Hampshire and Maine with Vermont as a wildcard.
Image: Total snowfall for the East through next Wednesday (2 part storm).
The west will likely see the ridge break down at some point around December 17th. Its impossible to tell where the storm track will line up but it’s likely that moisture returns to some spots of the Northwest and Rockies. Confidence is high on the ridge breaking down in the west. My confidence is less on how much snow or areas that will be favored. Lets only hope for an event similar to Thompson Pass or at least keep it in your dreams.
Image: Ridge is weakening over the west (Time stamp Dec 18).