Environment Canada has issued a heat warning for Metro Vancouver and the Fraser Valley, with extreme temperatures expected in the region over coming days.

On Labour Day, temperature records were already broken in parts of B.C. — including Abbotsford, Squamish, and Bella Bella — by 2 p.m. PT.

Temperatures climbed to the mid and upper 30s inland, with heat forecast to continue through Tuesday into Wednesday.

Environment Canada is warning to watch out for heat illness, especially young children, seniors, pregnant women and people with chronic illness.

"Extreme heat affects everyone," the warning states.

It's a HOT one out there this Labour Day! As of 2pm we've already broken daily maximum temperature records in <a href="https://twitter.com/hashtag/Abbotsford?src=hash">#Abbotsford</a> & <a href="https://twitter.com/hashtag/Squamish?src=hash">#Squamish</a>. <a href="https://twitter.com/hashtag/BCwx?src=hash">#BCwx</a> —@ECCCWeatherBC

Meanwhile, Metro Vancouver issued an air quality advisory for the region Monday as wildfire smoke is also forecast to return from B.C.'s Interior and Washington state.

Environment Canada says the current weather pattern could allow the smoke concentration to increase in some areas.

The agency said an unusually strong ridge of high pressure is building over the region. This type of weather pattern leads to a stagnant airmass, it explained, allowing smoke to linger.

Smoke from fires burning in Washington state, pictured, and B.C.'s interior is again expected to blanket Metro Vancouver, prompting an air quality advisory. (Amanda Cowan/The Associated Press)

On the other hand, if there is a substantial concentration of wildfire smoke, it could block sunlight and significantly lower daytime temperatures.

A weekend of hot, dry weather led to a flare up of wildfires across the province. Hundreds of new properties are under evacuation alert or order, and many communities in the Interior are rated high risk under Environment Canada's air quality health index due to wildfire smoke.