A blizzard warning has been issued for the Spokane region.
The National Weather Service originally predicted severe winter weather would hit the region starting at 7 p.m. and continuing until 10 a.m. Tuesday. The agency later bumped up the warning to start at 2:55 p.m. today.
New snowfall during the storm will measure 3 to 6 inches, the agency forecasts. Brisk north wind up to 25 mph will accompany the snowfall after 7 p.m.
Some gusts near Sandpoint, Bonners Ferry and Omak could reach 40 mph.
At 2:20 p.m. today, the Washington State Department of Transportation said it closed Interstate 90 eastbound 5 miles west of the Cascades summit due to severe weather and multiple spun-out vehicles and collisions. The agency and the Washington State Police are working to clear the roadway.
The closure is at milepost 47 near Denny Creek.
The blizzard warning applies to the Upper Columbia Basin, including Spokane, Ritzville, Grand Coulee, Odessa, Wilbur, Cheney, Davenport and Rockford. A map on the National Weather Service website shows the blizzard warning extending south to Pullman, north to the Canadian border and east into the Idaho Panhandle.
Road conditions will be icy with reduced visibility, the Weather Service cautioned. High profile vehicles may have trouble negotiating slick highways against the wind.
Although snowfall is expected to taper off Tuesday morning, increasing winds will likely lead to areas of blowing and drifting snow.
Snowfall totals for Monday and Tuesday are expected to be 6.2 inches in Spokane, 5.9 inches for Coeur d’Alene, 1.6 inches for Colville, 6.4 inches for Pullman and 4.0 inches for Ritzville.
Snow cover may shield young winter wheat from damage, and it may help protect ornamental garden plants that are sensitive to below-zero temperatures and wind.
A new snow storm is being forecast for Thursday evening into the weekend. “This frontal system is going to attack our region in two phases,” said forecaster Greg Koch. Snow would initially fall Thanksgiving night and again on Friday night and Saturday.
Even more snow is likely next week as December arrives, Koch said.
A deep low pressure area was forming along the Washington coast today beneath a sharp curve in the jet stream, which is flowing out of Alaska and Canada. The surface low which is producing the snow is expected to migrate along the Oregon-Washington border tonight, creating a strong pressure gradient between the low and arctic cold air moving southward with unusually high air pressure.
As the low moves to the south and east, it will draw cold arctic air behind it. Lows should reach the single digits tonight and then drop to below zero on Tuesday night.
Temperatures will begin to moderate on Wednesday night and Thursday, but still remain in the single digits and teens.
Wind chill tonight could reach minus-12, forecasters said.