Strong thunderstorms with torrential downpours to hit part of southern Ontario

Strong thunderstorms are expected to hit part of southern Ontario.

Environment Canada has issued thunderstorm outlooks, with the most significant storms expected late Wednesday or overnight into Thursday morning.

Here’s a look at what forecasters are predicting:

Wednesday p.m.

Scattered thunderstorms are expected in the afternoon and evening for areas labelled location A on the map below, which includes portions of northeastern, central, and eastern Ontario, including the Ottawa area.

Some could produce 70 km/h wind gusts and nickel-sized hail, forecasters said.

Up to 25 mm of rain is possible locally.

Other areas highlighted in grey, which includes portions of southern and northern Ontario, could see isolated thunderstorms in the afternoon and evening.

Parts of southwestern Ontario, including Windsor, (location B), are expected to see strong storms with heavy rain and strong winds.

They could begin in the late evening, “although confidence is low that these would occur before midnight,” forecasters said.

Thursday

As mentioned, portions of southwestern Ontario (location A below) are expected to see strong thunderstorms.

“Strong thunderstorms will move into the area from Lower Michigan, possibly by the late evening (Wednesday),” Environment Canada said.

“These storms will give torrential downpours and local rainfall amounts up to 40 mm. Strong wind gusts up to 90 km/h may also be associated with these storms. On Thursday afternoon, weaker isolated thunderstorms may again develop north of Lake Erie.”

Power outages are possible.

There may also be flash flooding and water pooling on roads, forecasters said.

Other areas highlighted in grey, which includes the rest of southern Ontario, are expected to see isolated thunderstorms that could drop up to 25 mm of rain, Environment Canada said.

Strong winds are also expected for much of the region.

Places along the shore of Lake Erie will see strong southwesterly winds up to 90 km/h, mainly overnight into the morning, Environment Canada said.

Winds of about 70 km/h could continue into the afternoon.

And other portions of southern Ontario will see gusts of 70 km/h to 80 km/h from the morning into the afternoon.

Maps via Environment Canada