Airport delays - power outages caused by storms - more expected Thursday

Hail covers the ground in Saint-Louis-de-Gonzague southwest of Montreal during strong thunderstorms Wednesday afternoon. More storms are expected on Thursday. (Photo: Amy Reynolds via Facebook)

A round of strong thunderstorms Wednesday afternoon impacted the extreme southwestern corner of the province, including the West Island portion of Montreal as well as Ile Perrot. The intense cells moved northeast from the New York state border region, later weakening over Laval by late afternoon.

The storms resulted in the loss of power to more than 60,000 Hydro-Quebec customers at the height of the outage. That number was down to 80 breaks Thursday morning, totaling just over 11,000 customers. Most of the damage to the power grid was caused by lighting strikes. Power was also out at Trudeau Airport and most of Dorval, resulting in major flight delays during the late afternoon hours.

The storms also produced significant hail across the region from Ile Perot southwest towards Valleyfield.

On Thursday morning, strong low pressure is lifting across the Great Lakes early, forecast to move north of Montreal to lie near the Gulf of Saint Lawrence on Friday. A warm front will produce heavy rain Thursday morning, followed by a break in the early afternoon. It will be a muggy day, with temperatures in the low 20s.

The trailing cold front will produce strong thunderstorms late afternoon in Montreal, with the risk of  gusty winds up to 90km/h, more hail, lightning and torrential downpours. The unusually strong June low pressure will also generate brisk winds outside of thunderstorm activity, gusting up to 70km/h into the evening hours and 50km/h on Friday. 

Wind warnings are in effect across a large portion of upstate New York and New England and may be extended into southern Quebec. Heavy rain with the storm has prompted warnings north and east of Montreal for up to 80mm of rain. Montreal can expect storm totals of 25-50mm. As of 8AM, 13mm had fallen here on Ile Perrot.

Strong winds both today and Friday may result in isolated tree damage and scattered power outages across the province.