'Intense' system to bring rising temps, strong winds and heavy rain to southern Ontario

Wednesday, February 19, 2014, 5:35 PM -

Southern Ontario is the target of another powerful storm.

Environment Canada issued a special weather statement early Wednesday warning of an "intense" system that will bring "rising temperatures to southern Ontario, but also significant precipitation and strong winds."

WARMING UP: Has it really been THAT cold in southern Ontario this winter?

"An Alberta Clipper will merge with a Colorado low to produce a strong system for the region Thursday into Friday," adds Doug Gillham, a meteorologist at The Weather Network.

Rain is expected to reach southwestern Ontario midday Thursday, then spread eastward to the Golden Horseshoe by the afternoon hours. 

Quite a range in temperatures at 7am; -10C in Kitchener/Waterloo & +4C in St. Catharines; Fair & 3C today - the calm before our next storm

— Doug Gillham (@gtaweather1) February 19, 2014

"As the precipitation spreads further north and eastward through the evening and overnight hours, it will encounter colder air and likely being as snowfall before changing to rain," EC says. "Some freezing rain and ice pellets will also be possible as the snow transitions to rain."

Strong wind gusts up to 80 km/h are possible along with isolated scattered thunderstorms that could produce locally higher rainfall amounts.

"Thursday night into early Friday morning, all regions of southern Ontario will experience rain with the exception of areas from about North Bay to Ottawa Valley, where a longer period of freezing rain is possible with an area of snow directly to the north of that freezing rain line," adds Dayna Vettese, another meteorologist at The Weather Network. "Non-severe thunderstorms are also possible Thursday night especially in southwestern Ontario. Rumbles of thunder are possible throughout southern Ontario as well."

Up to 30 mm of rain is expected in southern Ontario Thursday night, while parts of northwestern Ontario and areas north of Lake Superior could see up to 30 cm of snow.

"As the cold front makes its way through Friday morning (west to east) across the region, a change back to snow or rain-snow mix is possible before the precipitation ends through Friday evening," Vettese says.

According to Vettese, forecast confidence is high that a hybrid low pressure system combining an Alberta Clipper and Colorado Low will impact all of Ontario Thursday, Friday and linger into Saturday for northern regions.

" Confidence is also high that this will be a potent winter storm for northern Ontario and a milder rain event for southern Ontario."

Vettese adds that forecast confidence is moderate as to precipitation types as the precipitation moves in to southern Ontario.

FLOOD CONCERNS

While many Ontarians are looking forward to this brief break from frigid winter conditions, significant snow melt due to the rising temperatures will be a concern.

Conservation authorities say they're monitoring the watershed to prevent ice jams that would impede the flow of rivers. They say ice in some waterways could be frozen right down to the sandbars, making it difficult for ice break up and movement on the rivers.

Heavy snow on many roadways is also a concern as many drains are blocked by the snow.

Residents are advised to clear their catch basins and stay away from any fast-moving bodies of water.

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