Potential tornado touches down in Danville as Quebec hit by violent storms

A possible tornado may have struck Danville in the Eastern Townships as high winds tore through roofs, causing damage and leaving tens of thousands of people in the dark Thursday night.

By mid-evening, Hydro-Quebec was reporting 20,000 power outages.

Just before noon on Friday, the number of outages had dropped to about 12,000.

This comes after Environment and Climate Change Canada (ECCC) issued a severe thunderstorm watch for the Greater Montreal area.

A summary from the weather agency on Friday said the storm produced winds of 100 km/h and hail stones as big as 4 centimetres in parts of central Quebec.

These conditions were also favourable to form a large-scale storm, known as a “supercell,” according to Alexandra Cournoyer, a weather spokesperson for the agency. “These are storms with a lot of energy, humidity and instability. These storms have all the necessary ingredients that could come together to form a tornado.”

The overnight risks were higher in the Eastern Townships, Montérégie and Centre-du-Québec regions.

“Obviously, these precipitation rates will vary locally because municipalities or cities directly in the path of the storm are likely to receive more precipitation than a municipality a few kilometres away from the storm’s centre,” said Cournoyer.

The storm ripped off roofs, broke trees and tore down hydro poles in places like Danville, Saint-Evariste-de-Forsyth in the Beauce, and Saint-Valérien-de-Milton in the Montérégie region.

Other areas further north, particularly Mauricie, Saguenay-Lac-Saint-Jean, Abitibi-Témiscamingue, Outaouais and the Laurentians, remain under a warning of “occasionally heavy” rain for Friday.

“It could fall at a fairly high rate. This could eventually lead to torrential rains that could increase sudden river flooding in these regions,” said Cournoyer.

All the same, humidity is expected to drop on Friday, along with temperatures, and return to seasonal norms.

“Starting on Saturday, depending on the prevailing winds and air masses, we will see a second wave of warm air from the United States arriving in parts of Quebec,” said Cournoyer. “The spell of milder temperatures will not last long. Already for the weekend and early next week, we are monitoring a heat wave with high humidex.”

With files from the Canadian Press.