'Major' winter storm headed for southern Quebec just before holiday weekend

A "major" winter storm system is headed for southern Quebec at the end of the week, prompting warnings to drivers ahead of one of the busiest travel weekends of the year.

• GET THE LATEST HERE: Major storm moving into Quebec Thursday night 

Climatologists have dubbed the storm headed to Ontario and Quebec just before the holiday weekend as a "weather bomb" due to a rapid drop in pressure in the weather system. 

Environment Canada has issued weather watches and warnings that stretch from Ontario to Atlantic Canada. A special weather statement is in effect for southern Quebec, including Montreal, Laval, Longueuil, and the Châteauguay-La Prairie area.

• EXPLAINED: What is a weather bomb

The weather agency describes the storm as a mixed bag of weather that is expected to bring heavy snow, rain, and freezing rain, as well as a "quite drastic temperature drop."

Here's how the storm will affect the region.

THURSDAY

Beginning Thursday night, the storm will start with "particularly heavy" snow as temperatures hover around the freezing mark, according to Environment Canada. 

"This weight, added to the snow already on the ground, combined with the strong winds expected, may damage some structures or tree limbs. Local power outages are possible," Environment Canada said.

Areas north of the St. Lawrence River can expect to see between 15 and 30 centimetres of snow Thursday night through Friday. Montreal could see about 10 centimetres of snow, which could cause tree branches to come down and possible power outages. 

Hydro-Quebec said its crews will be monitoring the storm. In a tweet, it shared a link with tips to prepare people in case of a power outage. 

The high for Thursday will be -2 C, with a low of -3 C for the evening. 

FRIDAY

The snow will transition to rain by Friday morning, with several regions getting "significant" rainfall amounts, Environment Canada said. There's also a risk of freezing rain during the transition from snow to rain on Friday.

In Quebec City, Environment Canada is warning about possible snow squalls late in the day.

In Montreal, it will be windy with a forecasted high of 7 C, with the rain expected to continue until the afternoon.

Temperatures are expected to plummet by the evening, turning the rain back into snow, with a chance of isolated pockets of freezing rain during the transition.

Strong winds gusting close to 70 km/h will cause blowing snow and reduced visibility. 

"Plan your travel and allow extra time to get to your destination this holiday weekend as hazardous driving conditions are expected," Environment Canada said in the weather bulletin. 

SATURDAY

By Saturday, snow squalls are possible over parts of southern Quebec as colder air sweeps over the Great Lakes.

Flurries are in the forecast with a high of -4 C under windy conditions. There's a 40 per cent chance of flurries into the evening, with a low of -7 C.

The high for Christmas Day is -6 C under cloudy skies with some flurries expected. 

Strong winds and blowing snow will continue through the Christmas weekend. 

MONTREAL STORM WATCH

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