Much of Western Canada is sweltering in uncharacteristically hot, humid weather that prompted widespread heat warnings and forced rolling blackouts in Alberta.

Record temperatures were expected to peak in Alberta on Tuesday, further straining the province's electricity grid and raising stress levels for organizers of the Calgary Stampede.

The mercury rose above 30 degrees Celsius in Calgary and other cities in the province, but the humidity made it feel as hot as 40 C in some areas.

Environment Canada issued a special weather advisory for the province Tuesday, warning residents to stay in air conditioned places and drink plenty of water.

Saskatchewan and Manitoba are also dealing with oppressive heat, with temperatures hitting 31 C in Saskatoon and Winnipeg.

The scorching temperatures, and resulting heavy use of air conditioners across the province put pressure on Alberta's power grid and forced officials to schedule rolling blackouts.

Adding to the woes, four coal-fired generation plants and two natural gas plants went offline on Monday in Alberta, though it hasn't been confirmed whether they went down due to the high usage.

Epcor, Edmonton's power utility, issued a directive for the city's utilities to reduce their electricity consumption as a result of the plant shutdowns.

Calgary, Edmonton, Red Deer and Lethbridge were all subject to blackouts.

In Edmonton, the blackouts caused chaos on the roads as traffic lights went out at about 40 different intersections.

City officials and police said Epcor didn’t warn them of the power outages, leaving officers scrambling to deal with the traffic nightmare.

“It’s unacceptable and we’ll have to find out what happened and what went wrong,” Mayor Stephen Mandel told CTV Edmonton.

Had the city been properly notified, it would have sent out news releases and posted messages on social media telling drivers to avoid affected roadways, Mandel said.

An Epcor spokesperson said the company had to act quickly once the generating stations went down, but there will be a debriefing to find out if the situation could have been handled better.

Wildrose Party and Opposition Leader Danielle Smith said the power plant shutdowns need to be investigated.

“There's only one way to describe it -- it's suspicious to have six generators go off at exactly the same time on a day that we have a spike in energy demand,” she said.

Smith and other critics said the blackouts are really about market manipulation, not energy conservation.

“Of course it's the government trying to use this blackout as an example of why they should continue building a bunch of transmission lines we don't need,” she said, referring to a controversial plan to build a new north-south transmission line in the province.

But government officials said energy providers were simply trying to deal with a huge spike in demand.

‘Land of the wind chill, not the humidex’

High temperatures are expected to last in Western Canada over the next few days.

The sweltering conditions are especially jarring for Albertans, who are not used to humidity, Environment Canada’s senior climatologist Dave Phillips told CTV News Channel Tuesday.

“You don’t get 30 degree temperatures (in Alberta) as often as you do in the East,” he said. “What is really shocking them is the humidity, the humidex. They are the land of the wind chill, not the humidex.”

The humidity can be attributed to one of the wettest springs on record in the province, Phillips said. Crops are now “growing feverishly” and driving up the humidex values, he said.

On Monday, Alberta broke 19 heat records and set a new record high temperature of 33.1 degrees at the Edmonton airport.

Temperatures across Edmonton are expected to remain at or above 30 degrees for the rest of the week.

Organizers of the Calgary Stampede have maintained they have escaped the power troubles largely unscathed so far.

Officials with the City of Calgary ensured the Stampede grounds weren't subject to the shutdowns, which would have resulted in a security risk.

However, a stage lost power inside the grounds, as well as a highrise. Officials haven't determined whether those outages were due to the high strain put on the grid, or planned shutdowns that went awry.

In southern Manitoba, the hot weather is affecting municipal water supplies, as residents try to keep lawns, parks and golf courses hydrated.

For example, the City of Winnipeg used nearly 19 million litres of water in a single hour on Monday.

With reports from CTV Calgary and CTV Edmonton