"There's no guarantee with weather — not in Canada, maybe in Malta or Cyprus or Honolulu... But our models are showing that we think that July and August and early September look like it's going to be warmer than normal from coast to coast to coast," said Dave Phillips, senior climatologist at Environment Canada.
No areas of the country are expected to see temperatures dip below historic averages, though some areas will hover around the usual level.
"But most of the country — if this forecast turns out to be correct — it will be one where Canadians (will say) 'boy, that was a warm summer,'" Phillips said.
The heat and humidity in the low-40s across southern Ontario and parts of Quebec so far this week may be a prelude to the summer weather story to come.
It's been "almost a dry run, or the opening act" to weather ahead, said Phillips.
"What you see is what you're going to get," he said, noting the agency's models are the most "confident" in predicting weather in Eastern Canada.
He added that much of the country had a warm spring: the warmest in 65 years and the ninth hottest on record, with temperatures generally a degree-and-a-half higher than usual.
Phillips said the West will also be hit with hot and dry weather, with the cross-country forecast heating up the most through July and August.
But Phillips said the forecasting algorithms can't quite put a finger on just how warm it will be.
And, he added, when the heat does arrive it may not stick around for weeks at a time. So don't pencil in a long trip expecting barbecue-friendly weather.
"It doesn't mean that the two weeks that you take for your holidays are going to be nice and warm and toasty," he said.
"It did last year but that's not always the case... But it will be warmer than normal and it will be everywhere."
Though summer officially began at 7:09 p.m. EDT Wednesday, Thursday is the first full day of summer.
Phillips said a hot, dry summer means a heightened risk for extreme meteorological events such as forest fires and tornadoes.
Last year saw several stunning examples of violent summer weather, like the blaze that decimated Slave Lake, Alta. and the twister that touched down in the southwestern Ontario town of Goderich.
Last summer saw the national average temperature up 1.1 degrees from the 1961 to 1990 average, the weather agency says. That made it the fourth warmest ever recorded.
"No models tell you how active or quiet the season is going to be. We just know that here in Canada, let's face it, we have summer severe weather."
He added: "We do know (that) on the lazy, hazy, crazy days of summer, you will get those moments where your life is passing in front of you, that you have to be careful what you do" outside.
So, Canada's top weatherman says, make sure you grab the forecast before packing up the camper.
"When you venture out for an enjoyable day, wherever it may be across Canada, always know what the conditions are going to be like, and if it requires postponing your event or just sitting out for a couple of hours until the system passes through then you'll be safer and happier with it."
CORRECTION: An earlier version of this story had an incorrect spelling for Cyprus. This version has been updated.
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