Thunderstorms bring heavy rain as sweltering heat continues in Ottawa

A look at the weather forecast in Ottawa for Sunday, July 13, 2025.

A band of severe thunderstorms brough heavy rain and wind Sunday afternoon as the nation’s capital continues to bake under extreme heat.

Environment Canada issued a severe thunderstorm warning earlier in the day for Ottawa and Gatineau advising of wind gusts of up to 90 km/h, 50 mm of rain and nickel-sized hail.

The weather agency lifted the warning at around 4:25 p.m. as the storm moved eastwards. A severe thunderstorm watch issued in the morning was lifted shortly before 5 p.m.

A risk of thunderstorms remains this evening and overnight.

A heat warning issued on Friday remains in place as a prolonged period of extremely hot and humid conditions continues.

Daytime highs are expected to reach 31 C in Ottawa on Sunday, but humidex levels could make it feel like 40. The heat is expected to ease somewhat Monday with hotter and more humid conditions returning on Tuesday.

The heat is forecasted to dissipate on Thursday.

Environment Canada recommends taking action to protect yourself and others from the heat, especially those who are at greater risk of heat illness.

Watch for the early signs of heat exhaustion in yourself and others. Symptoms may include headache, nausea, dizziness, thirst, dark urine and intense fatigue. Stop your activity and drink water.

Call 911 if anyone is showing signs of heat stroke.

The City of Ottawa has a map showing places where residents can cool off.

Ottawa weather

A mix of sun and clouds Sunday with a 30 per cent chance of showers changing to a 70 per cent chance of showers this afternoon. Risk of a thunderstorm this afternoon.

High 31 C. Humidex 40.

Tonight will be mainly cloudy with a 70 per cent chance of showers changing to a 30 per cent chance near midnight. Risk of a thunderstorm this evening and overnight.

Monday will be sunny with a high of 30 C which could feel like 37 with the humidity. The evening will be clear with a low of 19 C.

Tuesday will be sunny with a high of 33 C.

Wednesday will be cloudy with a 30 per cent chance of showers. High 33 C.

The early weekend outlook shows a break from the extreme heat with highs in the mid-20s.

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