A significant Pacific storm has spread from the northwest coast across the Inland Northwest today and is expected to continue bringing moisture tonight through the early hours Saturday.
Mostly rain is expected in lower elevations and snow in the mountains although lowering snow levels early Saturday could affect parts of North Idaho as far north as Shoshone County as well as the central Panhandle and southeast Washington.
Rain with small amounts of snow began falling in Spokane about noon today.
The chance of rain is 80 percent tonight and 40 percent on Friday. The chance of rain or snow is 80 percent on Friday night and 20 percent on Saturday.
Snow levels should climb to 4,000 feet across Northeast Washington and North Idaho mountains tonight through late Friday, but then fall across the region by early Saturday.
During the middle phase of the storm on Friday, highs may reach the middle 50s.
The low in Spokane and Coeur d’Alene should be near freezing in the low 30s on Friday night.
By early Saturday, a cold front passes through the area, lowering snow levels enough to raise concerns about significant snowfall in southeast Washington, the North Idaho mountains from the central Panhandle northward to Shoshone County and the higher elevations of the Palouse region.
Temperatures should drop back to the middle 40s on Saturday, and cumulus clouds are likely to gather around the region.
Spokane should see a 20 percent chance of rain or snow showers before 10 a.m. Saturday, and then only a slight chance of showers after that.
National Weather Service forecasters said the storm could bring moderate amounts of precipitation, and several inches of new snow to mountain areas.
That should help boost a thin snow pack in the region.
At Snoqualmie Pass on Interstate 90, snow snarled traffic this morning, but pavement was clearing with some slush by afternoon. Snow levels are expected to rise above the pass tonight and Friday. Snow showers are possible there on Friday night and Saturday.
The weather service on Monday reported that the water equivalent stored in the snow of the Spokane River basin, which extends into the mountains east of Lake Coeur d’Alene, had dropped to 49 percent of normal.
Elsewhere, the average snowpack in Washington state was about 70 percent of normal earlier this month.
Cooler conditions Saturday night with lows in the upper 20s should give way to improving weather on Sunday through Tuesday with highs going from the lower 50s Sunday to near 60 degrees by Tuesday.
Daylight savings time starts on Sunday.
Spring arrives on March 20 with the vernal equinox at 10:32 a.m.