After several days of wildfire smoke hanging over Seattle, blue skies returned above the city on Saturday. According to the state Department of Ecology’s forecast, air quality in the Puget Sound region will remain good or moderate through Monday, while westerly winds carry smoke eastward. Seattle’s air quality index ranged from 14 to 56 on Saturday. Readings above 50 are considered moderate and are generally safe for most people, but may pose a risk to residents sensitive to pollution.
Puget Sound is a large Pacific inlet that moderates the region’s climate and helps mix the air. Daytime breezes from the water can dilute and push smoke away, while nighttime winds can change its direction. However, the inlet’s influence varies across the metropolitan area: proximity to the coast, terrain, elevation, development density and temperature inversions all affect how quickly pollutants disperse. As a result, areas near the water may clear more quickly, while valleys and areas behind hills can retain smoke longer.
National Weather Service meteorologist Dustin Guy said that, thanks to the influx of air from the coast, smoke would continue moving away from Seattle early next week. Only light haze, cleaner air and cool weather are expected, with daytime temperatures in the middle of the week remaining around 70–79 F (21–26 C). Little rain is expected, however, so dry conditions and a high risk of fire spread will persist.
Outdoor fires, including campfires and backyard fire pits using wood or charcoal, have been prohibited in King County and Seattle since Friday. A statewide burn ban has been in effect since Aug. 1. Specific restrictions in Washington depend on the location and type of fire: the state Department of Natural Resources regulates land under its jurisdiction, federal agencies oversee national forests and parks, and cities, counties and local fire districts may impose additional bans.
In some cases, the rules allow the use of gas or propane devices, designated fire pits or cooking equipment, but such exceptions depend on the specific order in effect. Violations can result in fines, reimbursement of firefighting costs and criminal charges if a fire causes damage. These requirements apply equally to visitors and residents. Officials urge extreme caution with any source of flames or sparks, because even a minor lapse in judgment can start another fire.
While air quality improved in the western part of the state, 13 counties in eastern and central Washington remained under air-quality alerts because of smoke from regional fires. In some places, the AQI could reach “very unhealthy” levels: near Entiat, it rose as high as 2,600 on Friday, while at the southern end of Lake Chelan it exceeded 300 on Saturday. Fires around Spokane had already burned more than 16 square miles and damaged or destroyed about 900 homes, buildings and other structures. As of Saturday, the Autumn Lane fire was 47% contained, Old Trails was 43% contained and Fairview was 31% contained. An extreme fire-danger warning across much of eastern Washington was expected to remain in effect until late Saturday evening.
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