Humidex advisories issued Tuesday warned that it could feel like 40 C or higher in many parts of central and southern Saskatchewan. Parts of east-central Alberta were also sweating it out during sultry summer days not much seen in recent years.
Dave Phillips, senior climatologist at Environment Canada, said humidex advisories aren't that common in a region better known for its skin-cracking dryness.
"Western Saskatchewan and also in Alberta, it's unheard of. It's very foreign," said Phillips. "It's not something that they even worry about.
"You pride yourself in (saying), 'Our cold is dry; our heat is dry.' Sometimes I think you think your precipitation is dry and that's not the case."
Phillips noted that Edmonton had an "unbelievable" humidex value of 39 on Monday.
Even Yellowknife was a sultry 30 degrees with a humidex value of 32. Phillips said the Northwest Territories capital usually has one day above 30 C every two years. It's been two so far this week, according to Environment Canada's website.
Humidex combines temperature and humidity — the amount of water vapour in the air — to reflect the perceived temperature. For example, the temperature in Regina at one p.m. Tuesday was 31 C, but with the humidity it felt like 40.
Humidex advisories are part of the lazy, hazy days of summer in Central Canada. It is an "odd thing" for the West.
"It's sort of something that is so Torontonian and that probably irritates westerners more than anything, to think that they're associated with Toronto. I guess about the only thing they don't have is the haze," said Phillips.
There are two sources for the humidity. One is a big high pressure system sending hot air up from the Gulf of Mexico.
"But I think the vast majority of the humidity is coming from homegrown sources, from local sources, all that precipitation you were cursing there in May and June," Phillips said.
"When you look at the map of total precipitation, it's a big purple blob there in typically the driest area of Canada."
Phillips said it was the third-wettest spring in 65 years on the Prairies and that precipitation is now evaporating.
Soaring temperatures drove Alberta's demand for electricity to an all-time summer high of 9,885 megawatts on Monday. People were asked to reduce electricity use, but that wasn't enough to prevent rolling blackouts. The Alberta Electric System Operator said demand Tuesday was expected to be as high or higher than Monday, but no blackouts were expected.
And hot and humid conditions prompted Manitoba's chief provincial public health officer to issue a heat advisory Tuesday.
The advisory said higher temperatures and humidity levels are forecast for an extended period for the whole province. Manitobans were urged to take precautions to prevent conditions such as dehydration and heat exhaustion.
Regina resident Lorraine Munro was trying to keep cool near the city's Wascana Lake.
"It's brutal," laughed Munro.
"I don't have air conditioning in my home, so I'm down here just to get some breeze off the lake and to get some shade and hopefully cool off a bit."
Munro joked that it's a great excuse to go to the mall when you don't have air conditioning at home.
Construction worker Tyler Murray was trying to keep cool while fixing an irrigation system in front of the Saskatchewan legislature.
"It's definitely pretty hot. You have to stay hydrated," he said.
"I know yesterday was pretty hot as well and I think I had maybe a little bit of heat stroke because I wasn't drinking enough water."
But Murray said he would take the heat over the cold.
"As much as I complain about the heat, it's still better than those -40, -30 winters. Yeah, I can't complain a whole lot because in about four months, five months, it's going to be pretty cold outside."
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