Hazy Skies, Red Flag Warning & Air Quality Impacts: WA Smoke Forecast

SEATTLE — After a run of milder days to kick off September, summer will be back with a vengeance through the weekend, and Western Washington may be in for its first brush with wildfire smoke of the season.

Forecasters expect high heat, wind and very low humidity will lend to a high risk for new fires igniting through Sunday. The National Weather Service has issued a red flag warning, which will take effect at noon Friday and remain in place through Saturday night.

At the same time, shifting winds are likely to filter in wildfire smoke from elsewhere, leading to hazy skies Friday around Seattle and potential air quality impacts on the ground.

"With easterly winds Friday and Saturday additional smoke is expected to move into the area, along with warmer temperatures," NWS Seattle wrote Thursday. "Moreover, critical fire weather danger is expected with the hot and dry conditions. Make sure to obey local burn bans as fires will be able to start and spread easily."

According to the Washington Smoke Blog, multiple fires burning along the Cascades could send smoke toward Puget Sound. In Eastern Washington, several counties will be under an air quality alert through Monday, due to additional smoke coming from fires burning in Oregon and Idaho.

In Western Washington, the Puget Sound Clean Air Agency said residents can expect some smoke Friday through the weekend, with air quality potentially declining to the "unhealthy for sensitive groups" range. The latest smoke forecasts predict "moderate" air quality in King, Pierce and Snohomish counties Friday through Monday.

As for the heat, the National Weather Service expects temperatures will peak Saturday. The current forecast shows the Seattle-Tacoma International Airport reaching 90 degrees Saturday afternoon, which would be a rare feat for September and set a new all-time record for days at or above 90 degrees in a single year at 13.

Temperatures should level off a bit Sunday, dropping back into the low 80s, before tumbling into the mid-to-low 70s to kick off next week.

Residents can find updated air quality forecasts via the Puget Sound Clean Air Agency and check for daily updates on the Washington Smoke Blog. Live wildfire smoke conditions are available using the EPA's AirNow tool.