An air stagnation advisory has been extended until noon Friday in the Yakima and Kittitas valleys, according to the National Weather Service.
Air quality was classified as unhealthy for sensitive groups in Yakima, White Swan and Toppenish on Tuesday afternoon, and unhealthy in Sunnyside, according to the state Department of Ecology.
Poor air quality may cause issues for people with respiratory issues, the weather service said.
A burn ban is in effect in Yakima County and the Yakama Reservation. No outdoor burning is allowed. Wood-burning devices are allowed indoors only if they are a home’s only source of heat, according to the Yakima Clean Air Agency.