Montreal weather this week: First frost of the season followed by a ‘record-warm’ Halloween

Buckle up, Montreal! The weather forecast for Quebec is calling for a stretch of chilly nights this week, bringing the coldest air Montreal has seen since March. But it won’t last long — by Thursday, we could see “record-warm” Halloween weather.

According to a new Montreal weather forecast from The Weather Network, the city is in for its first major frost this week, as temperatures are set to drop below freezing for the first time this season.

So far this fall, Montreal has avoided dipping below zero, with lows holding at a balmy 0.80 degrees — but that’s about to change. The Weather Network forecasts “two of the chilliest nights of the fall season,” with lows hitting minus 9 in some areas on Monday night, making it the coldest October weather since last year.

Here’s what the Montreal weather forecast has in store for us this week.

Frosty nights ahead

On Monday and Tuesday, much of southern Quebec, including Montreal, can expect nighttime lows in the minus 1 to minus 9 range, according to TWN. A notable high-pressure system sweeping in on Monday will bring clear, calm conditions, setting the perfect stage for the season’s first frost.

Eastern areas like Saint-Georges, Quebec City, Sherbrooke and Trois-Rivières will see temps around minus 5 to minus 9 on Monday night, while Montreal will drop around minus 3 and Gatineau might only go down to minus 1.

This significant drop in temperature is a couple of weeks later than usual, with Montreal typically experiencing its first frost by mid-October. Along with the frost comes a reminder for Montrealers to bring in any outdoor plants and be mindful of increased heating costs, as the chill will likely stick around for a couple of days.

A quick 180 in time for a warm Halloween

After this early-week cold snap, things will warm up a bit by Wednesday. Temperatures are set to climb to a high of 20 degrees, making way for what might be one of the warmest Halloweens on record in Montreal. The Weather Network suggests highs could hit the upper teens and lower 20s on Thursday, with a gusty southwest wind blowing through.

While it’s looking like a treat temperature-wise, trick-or-treaters should still keep an eye out for tricky rain. A cold front could bring showers to Montreal on Thursday evening, potentially dampening Halloween plans.

So, Montrealers, get ready to bundle up early in the week, but keep the lighter layers handy for a milder — and possibly rainy — Halloween night!

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