An Air Quality Alert has been issued by the National Weather Service. 
It is in effect from 6 PM this evening to midnight PDT Tuesday night. 

Smoke from wildfires in Eastern Washington and Montana will drift 
westward across Western Washington through Tuesday night. The 
central Puget Sound Region and the mountains will be the most 
impacted by the smoke. Expect the air quality to become unhealthy for 
sensitive groups late tonight through Tuesday evening. 

Conditions are expected to begin improving Tuesday night, but even 
more so on Wednesday, as marine air pushes inland and southerly flow 
aloft pushes the smoke out of the area. 

Children, the elderly, and individuals with respiratory illnesses are 
most at risk of serious health effects. These groups should limit or 
avoid time outdoors. 

If you have not already noticed the smoke in the upper atmosphere or heard it on the news there is an air quality alert in effect for western Washington.