Thursday, September 14, 2017
Central Washington smoke under cooler conditions
With the northerly winds over central and eastern Washington today, downwind impacts of wildfire smoke will be of concern.
Of the highest concern are the Upper and Lower Yakima River Valleys, the Methow Valley, and the lower Columbia Basin. For today, expect downwind communities in the above mentioned valleys to experience Unhealthy for Sensitive Groups to Very Unhealthy for most to today through tomorrow morning.
After the winds die down, we can expect fire growth to have occurred, which means more smoldering, especially as cooler temps prevail. Wildfire smoke under cool conditions causes the smoke to gather in valleys overnight and will accumulate until the sun heats the air and smoke, lofting the smoke up.
Expect the Colombia Basin, Okanogan, Chelan, Douglas, Kittitas, Yakima and Klickitat Counties will have compromised or diminished air quality once the northerly wind slows down.
Posted by CBennett ECY at 9/14/2017 11:28:00 AM