Ice Storm — Cascades of Snohomish and King Counties, Washington

2022-12-23 to 2022-12-24 · Cascades of Snohomish and King Counties, Washington

Event narrative

Freezing rain plagued the Passes during the early morning hours of Dec 24 as cold air lingered near the surface. Both Passes were closed around 6am due to freezing rain accumulation of around 1 inch. US 2 was closed into far western Chelan county and I-90 was closed from North Bend to Ellensburg.

Wider weather episode

After a series of snow events in the lowlands and mountains of western Washington, a system off the Pacific brought a modifying airmass towards the area right before the Christmas holiday. Warmer Pacific air was able to overrun lingering cold air very near the surface, producing a warm layer of classic characteristic of a freezing rain profile. As such, measurable ice accumulation led to hazardous impacts across the area, most noticeably to roadways and travel.

Source: NOAA Storm Events Database, event_id 1073548. Narrative written by the NWS forecast office that issued the report.