Heavy Snow in East Slopes Northern Cascades, Washington

A CoCoRaHS observer, 6.8 miles north-northwest of Winthrop, recorded a 48 hour total snow accumulation of 12.5 inches.

A new winter system moved in as a trough dropped into the Pacific Northwest on December 21st. With the accompanying atmospheric river, this system had substantial moisture with it bringing a wet and windy day ahead. Most of Eastern Washington was still too warm for snow, but there was moderate snowfall in the east Cascade slopes. Throughout the remainder of the region, locations received 24 hour rainfall totals up to 0.5 - 1.0.

In addition to wet conditions, the evening of the 21st into the early morning hours of the 22nd were windy, with damaging winds in the Palouse. The strongest winds were in far Eastern Washington, from Spokane to Pullman, and Cascade slopes. There were sustained winds 20 - 30 mph with gusts to 35 - 50 mph for over a 12 hour period. It was windy for much of the region, but much lighter with gusts to approximately 20 mph. Numerous power outages occurred in Chelan, Whitman, and Stevens counties.