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yesterday

Major Atmospheric River Hits Pacific Northwest, Flood Watches and Warnings in Effect

Forecasters say a prolonged, high‑intensity plume could drive multiple Western Washington rivers toward moderate to major flooding.

Highway digital billboard during snow storm in the Sierra Nevada mountains that reads, "Unsettled Weather Expected, Carry Chains." Oncoming headlights from cars visible.
A map from the National Weather Service (NWS) shows areas at risk of flooding as an atmospheric river takes aim at the West Coast on December 6, 2025.
Satellite image of the first atmospheric river moving over the US West coast on December 5, 2025. Credit NOAA GOES-19, Zoom Earth, The Watchers
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Overview

  • Heavy rain begins Monday and persists through midweek, with the strongest surge expected Monday night through Wednesday and river crests likely Wednesday and Thursday.
  • National Weather Service flood watches cover western Oregon and Washington through late week, with targeted flood warnings issued for rivers including the Wilson, Johnson Creek and Grays River.
  • Forecasts call for roughly 3–5 inches across Puget Sound and 6–10 inches or more along the coast and mountains, with the Olympics and Cascades favored for the highest totals.
  • The Snoqualmie near Carnation and the Snohomish near Monroe are projected to reach major flood stage, with the Skagit approaching major, and widespread urban and small‑stream flooding possible.
  • Saturated soils, king tides and gusty winds up to 50 mph heighten risks of landslides, coastal inundation and power outages, while snow stays mostly at higher elevations with occasional pass impacts.