Seattle Weather as Western Washington Braces for Wind, Rain, and Hazardous Cascade Travel Through Thursday
Seattle weather is shifting back toward wintry conditions as Western Washington braces for a stormy stretch featuring lowland rain, intensifying mountain snow, and strong winds peaking Wednesday evening (ET), with hazardous Cascade travel expected overnight into Thursday.
What Happens When Seattle Weather Meets an Atmospheric River Through Thursday (ET)?
An extended plume of moisture, described as an atmospheric river, is expected to move into the Northwest tonight through Thursday (ET). The setup is expected to bring steady precipitation, while snow levels are expected to remain near pass level rather than rising significantly. For the lowlands, the outlook centers on periods of cool March rain Wednesday, keeping conditions damp for both the morning and evening commutes. High temperatures are expected to reach about 50 degrees in the metro area, close to normal for this time of year.
In the mountains, snow is expected to intensify later Wednesday (ET). A winter storm warning is in effect for the Cascades, where an additional 1 to 2 feet of snow is expected in the next 24 hours. The Cascades already have fresh snow, with nearly 3 feet reported at Stevens Pass in the past 48 hours. By Thursday (ET), winds are expected to ease, but rain in the lowlands and snow in the mountains will continue, with snow levels expected to remain near 2, 000 feet through Thursday and Friday (ET).
What If Wednesday Evening Winds Trigger Tree Damage and Power Outages (ET)?
By Wednesday evening (ET), a rapidly strengthening area of low pressure is expected to move through Western Washington, shifting conditions from steady precipitation to a more wind-driven period. Southerly winds of 30 to 50 mph, with gusts up to 55 mph, are expected across the region, including along the coast and through Puget Sound. The strongest winds between Kitsap and King counties are expected between 7 p. m. and 11 p. m. (ET). A wind advisory is in effect, and gusty conditions could cause tree damage and power outages.
As the storm moves east (ET), winds are expected to shift to the west in the Strait of Juan de Fuca and the San Juan Islands. Gusts of 40 to 55 mph are possible in areas such as Oak Harbor, Port Angeles, and Anacortes.
What If Cascade Travel Turns Hazardous Under Blizzard Warning Conditions (ET)?
Strong winds combined with heavy mountain snow have prompted a blizzard warning for parts of the Cascades and Olympics from 6 p. m. Wednesday to 5 a. m. Thursday (ET). Winds could exceed 60 mph near mountain peaks and remain strong near the passes. Travel across the Cascades is expected to be hazardous on Wednesday night (ET) as snow intensifies and winds increase.
Looking beyond Thursday (ET), another push of colder air is expected Friday night into Saturday (ET), lowering snow levels to about 500 feet by Saturday morning. Some brief, light accumulations of lowland snow are possible, and high temperatures on Saturday are expected to struggle to rise much above the lower 40s (ET). Conditions are expected to improve Sunday and Monday (ET), with drier weather and increasing sunshine, and highs could approach 60 degrees by Monday afternoon (ET). Until then, Seattle weather remains in a late-season pattern of rain, mountain snow, and periods of impactful wind.
