SEATTLE (AP) — Poor air quality from wildfire smoke that's forced even healthy adults indoors in the Seattle area is expected to ease up later Wednesday, though officials warn that some of the hazy conditions may still appear into Thursday.

The National Weather Service's air quality alert extending from the San Juan Islands to the foothills of the Cascade Mountains is in effect until 5 p.m. Wednesday.

The Puget Sound Clear Air Agency cited the unhealthy air quality to urge people indoors, including healthy adults and those with sensitive health considerations such as children, pregnant women, the elderly and those with heart or lung problems.

A large-scale weather pattern shift will bring cleaner air for the region but that may not happen until late Wednesday night, so smoke may still be visible Thursday.