Conditions are favourable for the development of severe thunderstorms, which may produce tornadoes, Environment Canada says.
The weather forecaster has issued a tornado watch for Ottawa-Gatineau. Strong winds of up to 90 km/h, large hail and torrential rain are possible.
“A line or area of thunderstorms is expected to push eastward through eastern Ontario this afternoon. The main threats with these thunderstorms will be strong wind gusts and a tornado threat,” the weather statement says.
“In addition, the moist airmass will allow for storms to produce torrential downpours.”
Environment Canada says tornadoes are dangerous and potentially life-threatening.
“Be prepared for severe weather. Take cover immediately, if threatening weather approaches,” the statement reads.
A tornado watch is also in effect for the cities of Brockville, Perth, Smiths Falls and Kingston.
Tornado watches are issued when atmospheric conditions are favourable for the development of thunderstorms that could produce tornadoes. Tornado warnings are issued when the threat is imminent.
In the event of a tornado, or if a tornado warning is issued, Environment Canada says to go indoors to a room on the lowest floor, away from outside walls and windows, such as a basement, bathroom, stairwell or interior closet.
Leave mobile homes, vehicles, tents, trailers and other temporary or free-standing shelter, and move to a strong building if you can.
Monday’s forecast
Environment Canada’s forecast for Monday calls for cloudy skies and a 40 per cent chance of showers late this morning. There’s also a risk of thunderstorms early this morning.
Showers with thunderstorms will begin early this afternoon with a storm bringing between 30 to 40 mm of rain. The high will be 23 C with the humidex at 28.
Thunderstorms are expected to end by this evening and will remain cloudy with a 40 per cent chance of showers.
Tuesday calls for more rain and thunderstorms. Between five to 10 mm of rain is expected.
Conditions are expected to improve later this week, with clouds expected on Wednesday and a mix of sun and clouds on Thursday. Temperatures will hold steady around 20 C.
The weekend forecast calls for sunny skies.