Rain, wind and mountain snow on tap for Thanksgiving in Seattle; could complicate travel plans

An active weather system is expected to bring scattered rain showers, gusty winds and snow in higher elevations to Western Washington just days before many travelers hit the road for the Thanksgiving holiday.

A winter weather advisory is currently in place for the mountain passes, and the National Weather Service (NWS) in Seattle is currently predicting that both Snoqualmie and Stevens Passes will see 4 to 6 inches of snow through Tuesday evening.

"An upper level trough will bring showers and mountain snow before activity tapers off this evening," the NWS wrote in their Tuesday forecast discussion. "A front will move through Thursday into Friday for rain and breezy winds."

Conditions will then briefly dry out Wednesday before another front reaches the coast and moves inland overnight. The heaviest rainfall is likely to occur Thursday evening, with Seattle expected to see up to an inch of rain through Friday morning. Areas farther south like Tacoma and Olympia could see 1.5 inches of rain over the same period.

River flooding is also likely Thursday, and the NWS expects that the Skokomish River in Mason County will reach flood stage. Wind gusts up to 35 miles per hour are expected to impact cities farther north like Bellingham and Mount Vernon, which are still reeling from last week's atmospheric river event. Localized power outages and downed trees from wind are possible.

"Along with yet another round of rains, this front looks to bring a return to breezy to windy conditions to the area with the primary focus being along the coast and the north interior including portions of Whatcom and Skagit counties as well as the San Juans," the NWS wrote.

Temperatures are expected to climb into the lower 50s on Thursday with the arrival of the weather front, and higher elevations are likely to see rain instead of snow as the week progresses.

Showers will start to taper off Friday after the holiday before another wet weather system moves over the region early Saturday morning. The heaviest rainfall in that front is expected over the Olympics and North Cascades and rivers are expected to remain elevated over the weekend.

The active weather could complicate Thanksgiving travel plans for those looking to hit the road Wednesday and Thursday. The Washington Department of Transportation (WSDOT) expects the heaviest traffic eastbound earlier in the week as travelers head to their destinations and westbound over the weekend. Due to ongoing staff shortages, WSDOT is also preparing drivers for reduced service on roads this winter, meaning closures during and after significant storms could be longer.

Those driving over the mountain passes should prepare for winter conditions: Eastbound Interstate 90 over Snoqualmie Pass was closed Tuesday morning due to icy conditions and several spinouts. Travelers can check current mountain pass conditions here.