Heat wave brings temperatures of nearly 40 C to Thunder Bay on Monday

Much of northwestern Ontario under orange heat warnings

Thunder Bay residents, and those across northwestern Ontario, were taking steps to keep cool on Monday as the city and region saw daytime temperatures soar.

Parts of northwestern Ontario remained under orange heat warnings on Monday. As of shortly after 3:30 p.m., Environment Canada's weather conditions web page showed temperatures of 39 C in Thunder Bay, while the hottest spot in Canada was the Armstrong airport, at 40 C.

"It's a massive area of high pressure centred right now in the state of Iowa, but it's generated heat advisories, heat alerts, heat warnings in areas across the Upper Plains states of the U.S., parts of Manitoba, across Ontario, the Great Lakes states as well and even into the province of Quebec," said Geoff Coulson, meteorologist with Environment Canada. "It's a wide-ranging system that's bringing much above seasonal temperatures."

Hot enough for ya? Heat wave grips Thunder Bay

Coulson said the long-term average high for this time of year in Thunder Bay is 24 C.

Environment Canada said the heat wave is expected to continue through Tuesday evening, and possibly into Wednesday.

Forecasts for Thunder Bay call for maximum daytime highs of 34 to 40 C, and overnight lows between 19 and 23 C.

"The fact that we're not cooling off overnight is just more stress on the human body and makes these heat warnings all the more powerful," Coulson said.

And in addition to the heat, people in the region are also experiencing smoke in the air from forest fires burning across northwestern Ontario.

"We've got in some cases a significant wildfire activity, especially to the west of Thunder Bay," Coulson said. "With the winds coming in from the west, we're seeing plumes of of this wildfire smoke moving eastwards towards the Thunder Bay area."

"That can lead to locally poor air quality readings in those areas under the influence of the wildfire smoke," he said. "So it's almost a double whammy. We're getting the heat and humidity already from the the large scale weather system, but then adding to it with concerns locally at least of of poor air quality readings due to wildfire smoke."

Environment Canada advised people to watch for early signs of heat exhaustion, including headaches, nausea, dizziness, thirst, and intense fatigue.

People are also advised that heat stroke is a medical emergency. Signs can include red and hot skin, dizziness, nausea, confusion, and a change in consciousness.

If someone is showing signs of heat stroke, call 911.