Weekend storm to dump snow on Pacific Northwest

Friday’s light snowfall across parts of the Inland Northwest was a warning shot of what’s to come starting tonight.

An inch of snow fell at Spokane International Airport. It slowed traffic in the Spokane area and set off numerous collisions.

Snow also was reported in North Idaho and parts of northeast Washington.

A more significant snowstorm is predicted to arrive tonight as milder air from the Pacific Ocean replaces the remnants of this week’s arctic cold.

Spokane is forecast to get 4 to 7 inches of new snow by early Monday with up to 9 inches near the Idaho border. However, higher temperatures are expected to shift the precipitation to freezing rain or rain, eliminating part of the snow layer.

Coeur d’Alene could see 5 to 10 inches by Monday with rain and freezing rain likely on Monday in both cities.

The Palouse region and Whitman County may see 2 to 6 inches. Sandpoint could see more than 8 inches of snow.

Computer forecast models showed that the snow should start in Spokane about 10 p.m., increasing in intensity at 4 a.m. Sunday and persisting through the day before becoming a mix of rain, freezing rain, snow or sleet on Sunday night or Monday morning.

The storm is carrying moisture from the subtropical ocean region north of Hawaii. It is being driven inland this weekend by a low pressure area that descended southeastward from the Aleutian Islands in southwestern Alaska this week.

Temperatures in Spokane will go from the upper 20s today to the lower 40s by Tuesday, helping wipe out the snowpack as well as icy patches left over from last weekend’s snow.

Timing of the change from snow to mixed precipitation was not certain, but forecasters said they believe that mixed precipitation is likely by 7 a.m. Monday.

Ice accumulations should be less than a quarter inch.

Mountain areas and northern parts of the Idaho Panhandle will see all snow through the weekend and on Monday.

The milder air should penetrate the lower elevations of North Idaho and northeast Washington by Monday night. Sandpoint could see rain showers by then with high temperatures rising to the middle 30s on Monday and Tuesday.

Lookout Pass could see 16 to 30 inches of snow through Monday. Other mountain areas, including the region’s ski resorts, could see deep snow as well through Monday.

National Weather Service forecasters said 10 to 20 inches is likely in mountain areas.

Snoqualmie Pass on I-90 in Washington should see several inches of snow before milder temperatures turn the precipitation to rain on Sunday.

The western slopes of the Cascades could see enough rain to trigger flooding of tributaries. Forecasters are calling for 3 to 6 inches of rain in the western Cascades.

Ice jams have been a concern on streams across areas south of Spokane as a result of this week’s freeze.