A weather system is expected to bring a “significant” amount of fresh snow to parts of the Cascades Tuesday through Wednesday morning, likely causing travel delays for drivers heading over the mountain passes. The system will also bring lowland rain and gusty winds to western Washington into Wednesday.
The Cascade snowpack has fallen a bit behind, currently trending slightly below the seasonal norm. But this next round of heavy mountain snow should help to reduce the deficit, according to KOMO News Meteorologist Kristin Clark.
Parts of the northern Cascades could get up to 24 inches of snow, with 20 inches of fresh snow possible in the Mount Baker Ski Area. Clark said Stevens Pass could get between 10-15 inches of snow by Wednesday morning, with 6-9 inches possible along Snoqualmie Pass.
Precipitation began to pick up in coverage and intensity Tuesday morning as a Pacific front pulled into port. Blustery conditions were reported in the lowlands Tuesday morning, with the strongest wind gust of 50 mph reported on Camano Island.
A rain/snow mix at the mountain passes will change to heavy snow by Tuesday afternoon as snow levels lower in the wake of the departing cold front.
The National Weather Service (NWS) issued a Winter Storm Warning through Wednesday morning for the Cascades of Whatcom and Skagit counties, including the Mount Baker Ski Area. Heavy snow is expected above 3,000 feet and total accumulations of 12 to 24 inches are possible, according to the NWS.
A Winter Weather Advisory will also be in effect for the same time period for Stevens and Snoqualmie passes. The weather service said additional snow accumulations of 7-18 inches are possible for the Cascades of Snohomish to Lewis counties. The most significant accumulations are expected to be at elevations above 3,500 feet.
Travel over the mountain passes may be difficult. Drivers should plan ahead, check conditions on the Washington State Department of Transportation website and make sure their vehicle is prepared for winter driving conditions.
That elusive sunshine finally makes an appearance on Wednesday, along with a 48-hour stretch of dry weather that lasts through much of Thursday. But increasing clouds by then signal the approach of the next Pacific storm.
Showers resume on Friday but will be lighter in nature with less wind as this late-week storm trends weaker and farther north.
Sunbreaks and lingering showers kick off the weekend on Saturday. Not long before steady lowland rain and mountain snow resume late Sunday. So, for those making the cross-Cascade trek early next week, expect winter driving conditions at the mountain passes again on Monday.