Severe thunderstorm watch in effect for Montreal

By now you know the drill in Montreal. We have a very unstable, warm and humid airmass in place, with a cold front arriving this evening. There is a risk for very strong thunderstorms today, a few capable of flooding downpours, strong winds, dangerous lightning and hail. Be weather aware today and  pay close attention to any weather warnings that may be issued. The best chance for thunderstorms will be very late this afternoon into the early evening in Montreal.

You know the drill by now in Montreal with this July producing countless thunderstorm days. A severe thunderstorm watch has been issued for southern Quebec for Friday afternoon into the evening hours. Thursday's heavy rain has left behind a very warm and humid airmass across the region. The low clouds and fog are in the process of burring off Friday morning, leaving behind a very muggy, warm and unstable airmass across our area. Temperatures will rise close to 30C (86F) this afternoon under partly cloudy, humid and hazy skies.

A rather strong cold front will arrive from Ontario this evening, igniting some strong to severe thunderstorms in the Montreal region. The storms will be scattered in nature, so not everyone will see one today. If they do occur, some will be capable of very heavy rainfall, gusty winds and hail. There is even the risk for rotation with some of the cells, so an isolated tornado can't be ruled out. The strongest storms will be from Montreal south and east of the city to the US border. Most of the activity will be in the late afternoon into the evening hours, before moving south into New York State by midnight and weakening overnight.

Saturday will cloudy and much cooler, with scattered showers and temperatures in the low to middle 20s.

We are closing in on the rainfall record for the wettest July in Montreal. As of Friday morning, Trudeau Airport had measured 176.2mm (6.93 inches) of rain for July. The all time record was 182.6mm (7.18 inches) set way back in 1980. We could break the record today, if storms occur close to the airport in Dorval. Many parts of the city have already received well over 200mm (8 inches) of rain this month.