SEATTLE — Western Washington could see hazy skies through the weekend as wildfire smoke drifts in from wildfires burning in Canada and eastern Washington.
Air quality is expected to remain moderate through Saturday for most of the Puget Sound area.
However, weak onshore winds returned Friday, improving air quality from Thursday, where eastern Pierce and Lewis counties saw air quality deteriorate to unhealthy for sensitive groups.
It appears to be light wildfire smoke, according to KING 5 Senior Meteorologist Rich Marriott. Most of the concentrated smoke is remaining above 6,000 feet of elevation.
When air quality is unhealthy for sensitive groups, seniors, children, pregnant women and those with preexisting conditions should spend less time outside and reduce strenuous outdoor activity, according to the Washington State Department of Ecology.
Onshore flow is expected to pick up later Friday into Saturday, which could clear out the air. However, wildfire smoke from the British Columbia fires has moved over the Pacific Ocean, so Marriott said a change in onshore flow would bring wildfire smoke into western Washington.
Heat Advisory issued
The hazy skies are coming as western Washington is experiencing a warm-up over the next few days. A Heat Advisory is in effect for western Washington through Friday at 9 p.m. Hot temperatures are expected to significantly increase the risk of heat-related illnesses for those who are sensitive to heat or don't have access to adequate cooling.
Friday is expected to be one of the hottest days of the week with high temperatures in the upper 80s to low 90s. However, the hazy skies could keep temperatures at bay, shaving off a few degrees off the potential highs, according to Marriott.
Fire risk in the Cascades will also increase over the same period with thunderstorms possible across the Cascade mountain range on Friday. A Red Flag Warning is in effect until Friday at midnight for the west slopes of the North Cascades above 1,500 feet.
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