Slow moving cold front bringing much needed rain to Montreal

A slow moving cold front has been lying just to the northwest of Montreal all day Thursday. That front will finally press southeast this evening, bringing with it a decent 15-25mm of rain for the Montreal region. Friday will be breezy, cloudy and cool, feeling very much like Autumn across southern Québec.

It has been a dry month and a dry summer. To date, Montreal has measured 41.2mm at Trudeau Airport this August, most of that falling on just a couple of days. This is well below the long-tern average for the month of 93.6mm. The lack of rainfall has been evident, with watering restrictions, dangerously low levels on area lakes and rivers and heat stress reported to crops, tress and even your lawn.

Thursday afternoon we are watching a very moist and achingly slow moving cold front draped from southwest to northeast, located just north of Montreal. This front is the dividing lone between a fall-like airmass and warmer more humid air to the south. As I write, Montreal is 24C (76F), while Ottawa is only 17C (63F). Along the front steady rain is falling, with a few rumbles of thunder.

That front will begin to affect the Montreal region late this afternoon and especially this evening and overnight. Steady rain will persist into the morning hours on Friday along with cooler temperatures. Rainfall amounts will settle into the 15-25mm range. Not a drought-buster, but certainly helpful.

Overnight lows will drop into the teens, and as winds back to the northwest, temperatures will struggle to rise on Friday under cloudy skies reaching near 17C (63F).  Saturday will be cloudy and cool as well, feeling more like September. But the news is not all bad for the long holiday weekend, with sunshine expected both Sunday and Monday, with daytime highs rebounding into the middle 20's. Nearly perfect late summer weather for the Labour Day holiday.