Hot days are here but it's the hot nights that are setting records
It's the nights, not the days, that are exceptional, Environment Canada says
A late-summer heat wave that is expected to see temperatures reach 30 Celsius in Manitoba is not likely to set any daytime records.
However, lingering heat through the overnight hours almost certainly will go into the record books.
"One thing that's unusual with this late-season warmth is how humid it is," said Brad Vrolijk, a forecaster with Environment Canada.
"More and more moisture in the air needs higher temperatures to really warm up, so we're probably not going to see any [daytime] records. We'll be close, but no cigar."
But the humidity will hold onto the heat longer, preventing the temperature from cooling off too much at night.
"So we'll see very warm overnight lows — record warmth," he said.
Feeling the heat
Winnipeg is expected to see daytime highs of 29 C and 30 C on Monday and Tuesday. The records are 33 C and 32 C, set in 1979 and 1989, respectively.
However, overnight lows in Winnipeg will be around 20 C on Monday and 21 on Tuesday. The record overnight highs for those dates — 17.8 C and 15.6 C — were set more than six decades ago.
The normal low for this time of year in Winnipeg is 6 C. The normal daytime high is 18 C.
Sunday got up to 28.6 C, falling short of the record of 32.8 C set in 1908.
In other places that are more dry, like in southeastern Saskatchewan, which is under the same high-pressure system, the daytime temperatures are rising closer to 33 C for Monday.
In Saskatchewan, the temperatures will drop to 14 C and then 9 C overnight.
"I don't want to hear anyone complaining," said Vrolijk, with a laugh, saying he was recently cycling to his Winnipeg office in gloves and a tuque.
The average overnight temperature this month in Winnipeg has been 7.7 C, including a low of 2.8 C back on Sept. 8.
This week's heat is being felt across the entire province, with highs of 27 C up north in The Pas, Thompson and Norway House.
Even as far north as Churchill, the temperature is expected to peak at 24 C by Tuesday, and only go down to 16 C overnight. Normals are 8 C and 2 C.
Vrolijk said a couple of low-pressure systems will likely bring clouds and some rain by mid-week but temperatures around the province are expected to continue well above normal.
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