Four more days of warm afternoon sunshine are in the forecast, but so is a change to cool, wet weather starting Friday night through early next week.
Air pollution has started to build up in the lower atmosphere. The Spokane Regional Clean Air Agency reported that small particles of mainly smoke and dust have caused pollution to rise into the moderate category this morning.
National Weather Service forecasters are calling for sunny skies and highs in the lower and middle 60s this week, with lows going from the middle 30s to lower 40s.
Higher air pressure is anchored over the region today, and is bringing stable skies along with an early-morning temperature inversion which is holding air pollution near the ground.
The 7 a.m. temperature at Spokane International Airport was 35 and 34 a Felts Field.
The cold weather has caused fog to form in some of the valleys of Northeast Washington and North Idaho, but daytime heating should dissipate the fog by 9 a.m., forecasters said.
Coeur d’Alene was considerably cooler at 28 and Deer Park, one of the region’s cold spots at this time of year, was 25. Pullman was 37.
The bright fall weather is likely to disappear with a series of storm systems that are expected to ride up along the western side of the high pressure system as the high slowly migrates to the east later on Friday.
Some of the storms may be fed by subtropical moisture off the Pacific Ocean, allowing for a chance of heavy rain in some locales, most likely on Saturday evening.
Cooler weather that arrives behind the storms could bring snow levels down to 4,000 feet in elevation in the mountains by Sunday afternoon, forecasters said, but accumulations should be light.
The weather service is observing winter weather awareness week, and is highlighting the need to be prepared for severe winter weather, including stocking homes and vehicles with emergency supplies.
During the coming months, meteorologists will be issuing advisories and warnings of approaching winter weather so that the public can be prepared for the storms.