Pacific Northwest Endures a Hot and Smoky October

After record warmth, the region is set to cool down this weekend.

Wildfires burning across the Pacific Northwest through a season of record-breaking heat and dry weather have spread a blanket of smoke across Seattle, Portland and other parts of the region, where residents are breathing some of the planet’s worst air this week .

Photographers looking to capture Seattle’s iconic skyline have found it shrouded in haze as the city carries the scent of a mass bonfire. While the warm temperatures seemed to offer an extended season of hiking and biking, the smoke kept many indoors.

The Seattle area recorded a high of 88 degrees over the weekend; the city has never recorded an 80-degree day so late into fall. But by this weekend, highs will drop into the 50s, bringing relief as a cool front spreads across the Pacific Northwest. Forecasters said that breezes could blow away the smoke, while rain douses lingering wildfires and the region gets its first true taste of fall.

“Good news: The rainy season is almost upon us,” declared the Washington State Department of Ecology.

The region has endured a series of record-setting heat waves in recent years, some of which scientists have determined were made worse by climate change ; more are expected as the world warms. Skies have been shrouded for much of September and October as easterly winds have blown smoke from wildfires lingering in the Cascades, bringing air quality to unhealthy levels. Some schools have canceled outdoor activities.

On Wednesday, weather stations throughout the Pacific Northwest were recording the worst air quality in the United States, while Portland and Seattle ranked among the worst big cities globally. Health officials urged people — especially pregnant mothers, children, older adults and people with chronic health conditions — to limit their exposure and encouraged them to use air-purifying fans, while officials near Portland banned wood-burning fires.