SEATTLE — Mount Rainier is invisible from this city. The Blue Angels, the Navy’s elite flight demonstration team, flew two weekend shows in chalky, smoky air.

Government officials have cautioned people about air quality in a region that is usually known, especially at this time of year, for pristine cobalt skies.

But that has not been the case since last week, as the Pacific Northwest has been inundated by plumes of smoke from Canada, where more than 20 wildfires are blazing. The region has also contended with record-breaking temperatures on some days.

And it’s not over yet. Residents can most likely expect another five to seven days of hazy conditions, said Steven Apfel, a manager at the western region headquarters of the National Weather Service.

“The wind flow is really weak, and you need the wind flow to help push the smoke out of the area,” he said. “We just don’t have any decent wind or strong storms coming in to scour out the smoke, so that’s why it’s hanging around.”

Seattleites, who spent the weekend lamenting how Mount Rainier has been completely shrouded in wildfire smoke, seemed able to think of just two good things resulting from the haze: easier sunset pictures and some relief from the heat wave, which pushed temperatures elsewhere in the Northwest over 105 degrees.

People complained of burning eyes, and some said the smoke had forced them to seek treatment for asthma and other breathing conditions.

Ashley Coil, a concierge at the Columbia Tower Club in Seattle, which is on the top floor of the 76-story Columbia Center, the tallest building in the city, said the smoke moved into the region at the worst time. The building usually offers one of the best sights to watch the Blue Angels zip around the city, Ms. Coil said.

But over the weekend, the smoke was so thick that the fighter jets could be heard but not seen.

“You couldn’t even see a few feet in front of you,” Ms. Coil said in an interview. “It’s pretty weird because usually you can see all of the city and the waterfront.”

The rampant devastation in Canada, declared the “Summer of Fire” by CBC News, has destroyed hundreds of homes. About 6,900 people are living under evacuation orders. And one man who lost his home during an Alberta wildfire last year has now lost his log cabin in British Columbia, the Canadian news network reported.

A #BlameCanada movement sprang up on Twitter. But the British Columbia fires, some of the worst in decades, aren’t the only source of the haze.

“There are several fires in the Pacific Northwest that have contributed to the smoke as well,” said Mr. Apfel, who estimated that there were currently about 16 large fires in Washington and Oregon. “Previous years have had quite a bit of rainfall, and you get a lot of vegetation — and when it dries up, that’s what starts burning when the fire starts.”

The haze was especially notable as it settled over the region’s two largest cities — Seattle and Portland, Ore. — but it also languished over farmland and rivers. And weather forecasters said the days of haze probably kept some temperature records intact as the region sweated beneath a high pressure ridge that compressed and warmed the air below.

Air quality has improved in parts of the West Coast as cool marine air has moved inland. But for those who are still peering through the haze, officials recommend taking precautions, like avoiding strenuous activity outdoors, to stem any negative effects. The Oregon Department of Environmental Quality has advised the most vulnerable to consider leaving the area altogether, as the wildfire smoke can lead to a higher risk of illness.