Severe thunderstorm watch posted for southern Quebec

In what has become an almost weekly event in Montreal this summer, a severe thunderstorm watch has been issued for Thursday. The main threat today will be heavy rain, but there is also the risk for strong winds and hail. The storms will arrive in the city during the late afternoon and early evening hours.

Another severe thunderstorm watch has been issued for most of southern and eastern Ontario, and southern Quebec through the evening hours Thursday. A cold front will move into moist unstable air late this afternoon across our region, with strong thunderstorms expected. The storms will develop around midday in Ontario shifting east and northeast into Quebec. The biggest threat today, as it has been most of this summer, will be heavy rainfall and the potential for flash flooding. This is especially true outside Montreal where the ground is saturated from recent heavy rainfall. Gusty winds are also possible along with the slight risk for an isolated tornado. Be weather aware today if you have any outdoor plans. As always lightning is extremely dangerous, so when the thunder roars go indoors.

The front should clear our region overnight setting the stage for a pleasant, cooler and less humid Friday. Enjoy it, the humidity and rain/storm threat returns for the weekend.

We have a very progressive weather pattern in place that has pushed front after front across the Saint Lawrence Valley every other day. The result has been more heavy rain for many parts of the province since the middle part of June. While the storm earlier this week produced only 11.4mm of rain in Montreal, amounts increased quickly once you left the island. On Ile Perrot, I measured 18mm, with 24mm falling in Saint Anicet, Quebec City 70mm and Gaspe 157mm. Large parts of southern and eastern Quebec recorded between 50-100mm.

This trend of alternating rainy and sunny days will continue into next week, as our excessively wet summer persists.