Summer-like weather will hold strong across the region for one more day today, but a vigorous cold front in the Gulf of Alaska is heading toward the region on Tuesday.
Forecasters are calling for highs today of about 80 in Spokane and Coeur d’Alene after a high of 78 on Sunday at Spokane International Airport. Coeur d’Alene hit 84 degrees. Even warmer temperatures well into the 80s are expected in Lewiston, the Columbia Basin, Okanogan Valley and Colville area.
A strong ridge of high pressure that brought the warmer weather over the past several days is moving eastward today and opening the door for migration of a cold low pressure system from off the British Columbia coastline, forecasters said.
Temperatures this morning at 7 were in the 50s and lower 60s, including 54 at the airport, 60 in Pullman, 52 in Sandpoint and 63 at Coeur d’Alene.
A cold front associated with the low pressure system should bring gusty winds of 15 to 25 mph in Spokane and Coeur d’Alene under partly sunny skies with a 30 percent chance of showers. The chance of showers will be higher in the northern mountain areas. Wind gusts could hit 30 to 35 mph through Tuesday evening.
Highs Tuesday and Wednesday should be in the middle 60s with lows dropping into the low 40s. Coeur d’Alene might see a low in the upper 30s on Wednesday night, along with other locations in the region, but the lows should remain well above freezing, forecasters said.
There is only a slight chance of thunderstorms in northeast Washington and North Idaho.
Snow melt triggered by the warmer weather since Friday is causing rivers in the region to rise, but all of them are expected to remain below flood stage. The St. Joe River at St. Maries should crest Wednesday at 30.6 feet below the flood stage of 32.5 feet, forecasters said.
Snow pack in the upper elevations remains above normal for mid-May with the exception of the northern Cascades and Okanogan area, which are below normal. The water equivalent held in the snow was at 111 percent of normal in northeast Washington and North Idaho as of Sunday night.
The forecast for Saturday and Sunday calls for sunny to mostly sunny skies. The northern portions of the region near the mountains should see a 20 percent chance of showers.
The outlook for the rest of the week calls for improving conditions through Saturday with highs going from the 60s to the lower 70s with cool conditions in the 40s at night.
Computer forecast models show the entire Pacific Northwest coming under a weak ridge of high pressure during the holiday weekend, suggesting the likelihood of mild to warm temperatures and generally sunny skies through next Monday.
Normal temperatures for today in Spokane are 67 for a high and 43 for a low.