Another stretch of hot and humid weather is set to break dramatically as Environment Canada has issued severe thunderstorm watches for much of southern Ontario, including London and Middlesex.
The national weather agency says a cold front will pass through the region overnight, bringing in slightly cooler and drier air on Tuesday, but conditions are favourable for storms to develop mid-afternoon on Monday and late into the evening.
Severe thunderstorm watches were issued late Monday morning while heat warnings remain in effect. Locally, an extended heat warning from the Middlesex-London Health Unit also remains in place.
Environment Canada says conditions are in place for the development of severe storms that could result in damaging wind gusts up to 90 km/h, as well as heavy rain.
Meanwhile, a sweltering hot July moves to a close. The forecast calls for a high of 31 C on Monday, feeling closer to 42 C with the humidity, and a high of 29 C on Tuesday with a humidex value of 34 C.
The forecast also calls for a 60 per cent chance of rain or thunderstorms in London, Ont., on Monday and a 30 per cent chance on Tuesday and Wednesday, when the high is set to reach a milder 23 C.