A torrent of warm air that started working its way east over the weekend has sent temperatures soaring throughout most of Canada, with many cities registering the kind of weather reserved for early summer.
The past weekend saw temperatures spike at least 10 degrees above seasonal norms in western and central provinces, Environment Canada said, adding the Maritimes are expected to follow suit in the coming days.
Before the week is out, all provinces east of British Columbia will experience temperatures in the double digits, leaving only B.C. itself and the territories to cope with typical seasonal conditions.
"As far as you can see on the weather map, it just seems to be temperatures are a dozen degrees warmer than normal," said senior climatologist David Phillips. "That is really shocking for this time of the year."
The groundwork for this latest twist in the country's ongoing weather saga was laid over the past three months, Phillips said, adding the unusually mild winter made the current temperature surge inevitable.
The balmy breezes that raised average winter conditions at least three degrees above seasonal averages also put a damper on typical winter precipitation, Phillips said.
Without snow on the ground, he said, the rush of warm air moving up from the south had nothing to counteract its effects and keep spring-like conditions from veering into summery territory.
Temperatures in Toronto hit 18 degrees on Sunday and are expected to pass the 20 degree mark later in the week.
Average temperatures in Calgary, Winnipeg and Montreal usually hover around the freezing mark at this time of year, but Phillips said those cities can expect highs in the teens over the next few days.
Temperatures will climb in the Atlantic provinces as the warm air works its way east, eventually pushing temperatures in Halifax at least 10 degrees above its seasonal norm.
Such a widespread warm spell is unprecedented. Phillips said the spike felled at least three temperature records on Sunday alone with more expected to fall as the week continues.
"It's so persistently mild. That, I think, has caught everybody by surprise," he said.
Forecasting sleuths could be forgiven for closing the file on winter 2012, but Phillips said the veterans know better.
Warm weather streaks like the one underway, he said, are usually little more than a red herring.
March is notoriously unpredictable and has historically offered most cities at least 10 per cent of their total snowfall for the year, he said. Despite this unusual lapse, Phillips predicts this month will be no different.
"When you look out your window and it looks like spring, almost summer-ish kind of weather, ... it's telling you that there's still usually some winter left in the year."
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