Environment Canada issues severe thunderstorm watch for Ottawa area

A person walks a dog along the Rideau Canal on a rainy day in Ottawa. Aug. 28, 2025. (CTV News Ottawa)

Environment Canada says severe thunderstorms could be on the horizon for Ottawa on Saturday.

The organization issued a Yellow Watch — Severe Thunderstorm on Saturday afternoon.

“Conditions are favourable for the development of severe thunderstorms that may be capable of producing strong wind gusts and heavy rain,” Environment Canada wrote.

Environment Canada says the thunderstorm could produce wind gusts up to 90 km/h, as well as hail. Some areas may experience multiple rounds of thunderstorms with rainfall totals nearing 50 millimetres.

“When thunder roars, go indoors! Lightning kills and injures Canadians every year,” Environment Canada said.

“Emergency Management Ontario recommends that you take cover immediately if threatening weather approaches. Heavy rain can cause flash flooding and significant reductions to visibility. Strong wind gusts can damage trees, buildings and overturn vehicles.”

Ottawa forecast

According to Environment Canada’s weather forecast, Ottawa residents should expect showers throughout the day on Saturday. Starting in the afternoon and continuing through the evening, there is a risk of thunderstorms.

The temperature will reach a high of 24 C, and the overnight low will be 15 C.

• Hourly and 7-day forecast on our CTVNewsOttawa.ca weather hub

On Sunday, there’s a chance of more showers and the temperature is expected to reach 23 C.

On Monday, expect a bright and sunny day with a high of 27 C.

On Tuesday, expect sunny skies and 29 C.

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