CALGARY -- Smoke is shrouding southern Alberta due to wildfires in Northwestern United States and health officials are warning people to take precautions.

Environment Canada issued the alert for southwest Alberta when ashy clouds blew in over the weekend, prompting health officials to warn people to avoid outdoor physical activity and recommend staying inside as much as possible especially those with lung conditions, seniors and children.

"Children just have a different respiratory system with their development and they tend not to pace themselves even when they go out into poorer air quality," said Stuart Brideaux with Calgary EMS.

Wildfires tearing through Oregon and California have destroyed thousands of homes and killed dozens of people in the United States. They also sent smoke up into British Columbia which has been under reduced visibility and poor air quality advisories for days. The conditions were expected to head east Sunday night and Monday morning.

"The conditions are going to slowly deteriorate. Possibly clipping Calgary as well as getting into the southern reaches with Lethbridge and Medicine Hat," said meteorologist Armel Castellan.

The smoky conditions arriving in Alberta are expected to worsen until Monday night when cooler air arrives.

"It’s both problematic actually because it’s going to mix the smoke down to the surface but it’s actually going to move and disperse some of that air as well," said Castellan.

While staying home, health officals advise closing windows and vents and, while in your car, run fans on recirculate to avoid symptoms from the smoke.

"Itchy throat, coughing, wheezing, and itchy eyes as well," said Castellan.

Though a mask might seem to help, health officials warn most medical and non-medical masks offer little to no protection from the smoke.

"The masks that most people are currently wearing for coronavirus reasons do not have the same effect unfortunately with the smoke," said Brideaux.

He explained that particulates that make up smoke are so tiny they pass right through masks like the cloth or blue procedural ones often used during the pandemic.

N95 masks are what's needed to keep you safe from smoke, however those are reserved for first responders so your best bet is to avoid the conditions, which are expected to blow over by the end of the week.