Summer snow for Lake Louise, warm in Montreal

Heavy wet snow greeted visitors to Lake Louise, Alberta on the last full day of summer. (Lake Louise Ski Resort Photo)

The last full day of summer was spectacular across southern Quebec and Ontario. Plentiful sunshine, gusty southwest winds and warm temperatures prevailed, with highs reaching 27C (80F) or better in many locations across southwestern Quebec. Humidity levels were elevated, making it feel more like mid-summer. Montreal should be around 20C (68F) for late September. While we were enjoying August-like weather here in the east, an upper-level low and cold northerly flow produced a widespread summer-snowfall across the foothills of Alberta. As much as 32cm fell across the higher elevations near Banff, with over 30cm at Sundre. A cold rain fell east of the foothills towards Calgary.

The coolest air so far this September will invade southern Quebec this weekend. (AccuWeather Graphic)

First Day of Autumn
Fall officially arrives at 10:21 a.m. Thursday morning, with cooler weather and clouds forecast to greet the season. Today will still feature above-normal temperatures in Montreal, just not as warm as it has been. Expect high temperatures in the low to middle 20s. A cold front will move from north to south across southern Quebec tonight and into New England on Friday. Expect a period of steady rain along the front, followed by gusty north winds and much colder temperatures. Highs on Friday will only be in the upper teens. High pressure will settle into Quebec Saturday and remain through Monday. The forecast will be cooler than normal for the first time this month. Highs on Saturday and Sunday will only be around 15C (59F), with lows down to 7C (45F) in the city, but much colder in outlying regions. Some locations may even see scattered frost early Sunday and Monday morning. Briefly looking ahead to next week, warmer weather will return, with temperatures once again surging above normal in Montreal.