Map Shows States Under Air Quality Alerts as Thousands Told Stay Inside

0 Share Newsweek is a Trust Project member See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. Air quality alerts spanned large swaths of the western United States on Sunday as wildfire smoke and high ozone levels triggered unhealthy breathing conditions across Oregon , Idaho , Washington , Montana , Colorado , and California .

Data from AirNow, the Environmental Protection Agency's ( EPA ) monitoring platform, showed widespread "unhealthy" air or worse, driven primarily by smoke from ongoing fires in Canada and the Pacific Northwest. Officials urged residents in affected zones to remain indoors, limit strenuous outdoor activities, and take precautions if they suffer from asthma, heart disease, or other respiratory ailments.

The primary health threat stems from fine particulate matter, known as PM2.5, which is small enough to penetrate deep into human lung tissue.

"Stay inside if possible. Keep windows and doors closed," warned an alert from the Oregon Department of Environmental Quality for Baker County, which covers over 16,000 residents and remains in effect through late Monday.

Newsweek reached out to the department by email for comment.

Oregon officials noted that particulate concentrations can shift rapidly based on shifting wind and weather patterns.

Conditions deteriorated into "unhealthy" and "very unhealthy" ranges across neighboring Idaho. The Idaho Department of Environmental Quality (DEQ) issued an advisory covering Ada, Adams, Boise, Canyon, Elmore, Gem, Owyhee, Payette, Valley, and Washington counties through Tuesday afternoon.

Additional advisories stretched across northern Idaho and the Nez Perce Reservation, warning of particulate levels hazardous to sensitive groups.

"Air pollutants can cause breathing difficulties for children, the elderly, as well as persons with respiratory problems," the Idaho DEQ said in an air quality alert. "Those individuals who are sensitive to increased particulate matter or smoke are encouraged to avoid prolonged or strenuous outdoor activity during this advisory. Open burning is prohibited by air quality rule. It is also recommended that all other individuals limit prolonged or strenuous activity outdoors."

Washington state also grappled with wildfire smoke, with AirNow flagging "unhealthy" air in north-central regions and "unhealthy for sensitive groups" across the state's northeast.

In Montana, the DEQ said it was issuing an air quality alert for Choteau, Granite, Hill, Lewis and Clark, Liberty, Missoula, Pondera, Powell, Ravalli, Teton, Toole counties because of elevated particulate levels from wildfire smoke. The alert is set to expire at 9 a.m. on Monday.

Meanwhile, pollution concerns in Colorado and California stemmed from ground-level smog rather than smoke. State forecasters issued an Ozone Action Day Alert for the Denver metro area and the Front Range Urban Corridor, where hot, sunny weather pushed ozone into unhealthy brackets for sensitive individuals. In California, the South Coast Air Quality Management District warned of elevated smog persisting through Monday evening across parts of Los Angeles County, including the San Fernando, San Gabriel, and Santa Clarita valleys.

Federal and state officials advised residents under active alerts to monitor local AQI readings frequently, as shifting weather can rapidly alter conditions.

Monday forecasts from AirNow indicate that heavy smoke impacts will shift further into Idaho and Washington, while air quality in Oregon is anticipated to begin improving. Public health agencies continue to recommend that vulnerable populations—including children, older adults, and those with pre-existing heart or lung conditions—minimize outdoor exertion and utilize indoor air filtration systems until alerts expire.

Contact Newsweek editors for this story: Steve Mollman and Anthony Murray .

Indexed and credited by AIPROPX. Originating outlet: Newsweek. Open at source →