A combination of orographics and isentropic ascent centered in the warm sector of an approaching Pacific storm system resulted in heavy snowfall across the northeast mountains of Washington. Warmer air eventually moved into the region and snow levels climbed above valley floors with heavy snow continuing in the mountains through midday on the 22nd.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS OTX wrote it up.
A combination of orographics and isentropic ascent centered in the warm sector of an approaching Pacific storm system resulted in heavy snowfall across the northeast mountains of Washington. Warmer air eventually moved into the region and snow levels climbed above valley floors with heavy snow continuing in the mountains through midday on the 22nd.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Spokane, WA wrote its last area forecast discussion before the first event at Nov 20, 2:44 PM PST, 14 hours 16 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
Valley snow accumulations ranged from 2 to 5 with locally up to 6 inches near the Canadian Border. 49 degrees North Ski Resort reported 23 inches of snow over the two-day period.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2011Every state in 2011This day in weather historyWarnings in Washington, November 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 351606.