Stagnant air over region means higher pollution through Monday
National Weather Service forecasters said today’s sunny weather is also bringing one of the region’s cold-weather hazards - stagnant and polluted air.
Forecasters this afternoon issued a stagnant air advisory for nearly all of Eastern Washington and North Idaho. Central Washington is included in the advisory, which is in effect until 4 p.m. on Monday.
Air quality in Spokane this afternoon was measured in the moderate range, with small particulates as the primary problem. Those come mainly from wood smoke.
No burning restrictions are in place today, but they are possible if air quality comes closer to the unhealthful range for people with lung and other health problems.
Forecasters said worsening air quality may occur gradually in coming days.
Higher air pressure has settled over the region after bringing a cold northerly flow overnight Wednesday and Thursday morning.
That cold air is now topped with milder air, which acts like a lid on pollutants in what is known as an air temperature inversion. The condition worsens at night through early morning hours, causing pollution levels to rise to higher levels during those times.
Dry and stable air will hold the pollutants in the lower atmosphere through Monday. The next chance of relief comes Tuesday but it is not likely to fully reverse the problem, forecasters said.
After a low of 14 tonight, temperatures should moderate to the 20s overnight and 30s during the day under sunny skies.