NEWS

Wacky weather mix across Canada

05/28/2012 01:48 EDT | Updated 07/28/2012 05:12 EDT

Canadians expecting a lovely spring day are getting more than they bargained for in many parts of the country today as weather forecasts look more like the dog days of summer or, in some cases, a winter freeze.

The major weather story is in southern Ontario, where hot and muggy weather rules the day and temperatures are expected to skyrocket well past the 30 C mark, with record temperatures possible for Toronto. Environment Canada has issued a special weather statement for all of southwestern Ontario, warning residents of poor air quality and smog which could make it difficult to breathe, especially for those with asthma or other lung problems.

"A low pressure system is tracking across the Great Lakes and is pumping in warm, moist air all the way from the Gulf of Mexico," said CBC meteorologist Johanna Wagstaffe.

Factoring in the humidity, the temperature in Toronto could feel like 39 degrees, with similar highs expected in Windsor, London, Kingston, and Ottawa. The average temperature for this time of year is around 21 C.

"That [temperature] is still pretty oppressive," said Wagstaffe, "just below advisory level — but enough that Environment Canada has said heads up, if you don't do well in the heat and humidity it's a good idea to stay inside, in the air conditioning today.

She said the record temperatures to beat include 32.5 C for Toronto, 31.6 C for Hamilton and 32.8 C for Windsor.

Trains are being delayed between Ottawa and Montreal as heat is causing railroad tracks to warp. The track, owned by the Canadian National Railway, has forced trains to slow down through areas where tracks expand and contract. This phenomenon called "sun-kinking" usually only happens in July and August, according to CN.

In northwestern Ontario, heavy rains have led to flooding in a number of communities. The City of Thunder Bay has declared a state of emergency after more than 100 millimetres of rain fell over the past 24 to 36 hours. The city's pumping station is also flooded and residents are being asked to avoid releasing any more water into the sewage system.

Colder weather expected in Maritimes

In Atlantic Canada, the weather story is markedly different. Temperatures in St. John's and other parts of Newfoundland and Labrador will be in the single digits, below seasonal averages. Rain and ice pellets are expected in St. John's, the possibility of trace amounts of snow. A special weather statement for the area says northern regions of the province could see a few centimetres of wet snow accumulation.

Frost warnings have been issued for overnight Monday into Tuesday morning for much of Nova Scotia, including Halifax, and Prince Edward Island as temperatures will dip near or below freezing. Conditions are expected to remain cooler than normal for much of this week before returning to seasonal on Thursday and Friday.

Farmers in P.E.I. are keeping a close eye on the weather, as the appearance of frost could mean problems for the province's strawberry crops. A strong crop this year would be put at risk if frost damages the delicate plants.

The weather story for the rest of the country shapes up like this:

- Rain and seasonal temperatures for Vancouver, Victoria and much of British Columbia.

- Sunny and warm for Calgary and Edmonton.

- Following cool and stormy weather for much of southern Saskatchewan on Sunday, including heavy rain in Regina and upward of 20 cm of snow in Cypress Hills Provincial Park, temperatures will begin to trend toward seasonal by the end of the week.

- Rain expected across much of Quebec, including Quebec City and Montreal.

- A sunny forecast for Yellowknife with the temperature expected to reach 24 C, nearly 10 degrees above seasonal.

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