According to air pollution monitors, fine particle pollution is at or above a level that is considered unhealthy for sensitive groups.
The NWS says this batch of dense smoke is expected to remain in the Yakima Valley and surrounding areas through Sunday evening and possibly into Monday.
Areas of Southwest Montana will wake up to some cloudy and drizzly skies tomorrow, but we are expected those showers to continue to move out by Wednesday.
"You can't hold as much air in your lungs, that's the natural part of the aging process, but it means the smoke might have more effect on you than a healthy younger person, especially if you happen to have some chronic disease", Henderson said.
During "very unhealthy" conditions, everyone is encouraged to stay indoors, avoid strenuous activity, close windows and doors, set air conditioners to recirculate, and use a HEPA air filter if possible.
Sunday's weather sees the continuation of the a special air quality statement for Metro Vancouver.
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Things have gotten better since then, especially with Windows 10 but it was far too late for the previous gen OS. On the desktop side, there was the forced touch-centric UI that gave desktop users no choice in the matter.
Smoke may not affect all areas at all times. Unhealthy air will be common across the lowlands.
Air quality statements blanket parts of western Canada as smoke from the more than 500 wildfires burning in British Columbia coats the region in some of the worst air quality in the world.
The poor air quality can be especially unsafe for people with preexisting heart conditions.
Doctors say if you feel unwell at all during the period of poor air quality to see a doctor immediately. You want a mask that either has "NIOSH" or "R95", "N95", or "P95", or higher printed on the packaging.
The Federal Aviation Administration said airplanes bound for the Seattle-Tacoma International Airport may be delayed because of low visibility.