Risk of tornadoes for parts of Renfrew County, Algonquin Park

A person holding an umbrella crosses Wellington Street as rain falls in Ottawa, Friday, Aug. 9, 2024. THE CANADIAN PRESS/Justin Tang

Environment Canada has issued a severe thunderstorm watch with a possibility of tornadoes in part of Renfrew County and Algonquin Provincial Park.

The weather agency says heavy downpours this afternoon could produce between 30 and 50 mm of rain.

"Thunderstorms are expected to develop and move across the region this afternoon. Despite it being early Autumn, a tornado or two cannot be ruled out," Environment Canada's weather watch said.

The thunderstorm watch includes the areas of Deep River, Chalk River and Laurentian Hills.

Severe thunderstorm watches are issued when atmospheric conditions are favourable for the development of thunderstorms that could produce large hail, damaging winds and torrential rainfall.

Tornado watches and warnings may be issued later in the day if conditions deteriorate. 

Ottawa weather

Expect a rainy commute in Ottawa on Wednesday morning and this afternoon.

Environment Canada's forecast says to expect rain throughout the morning, then cloudy with a 40 per cent chance of showers this afternoon.

Between five and 10 mm of rain is expected.

Rain showers will continue into the evening, with about 10 to 20 mm of rain forecasted overnight.

Temperatures will remain steady near 16 C.

Showers are expected to continue on Thursday, with rainfall forecasted to end near noon. There is a also a chance of a thunderstorms in the morning and in the early afternoon.

Conditions are expected to improve by Friday, with sunny skies and a high of 23 C.

The weekend forecast shows clouds with high temperatures near 23 C.