Severe thunderstorms and tornadoes

Get severe thunderstorm and tornado alerts

About severe thunderstorms

Thunderstorms can create very strong winds, hail, heavy rain, and sometimes even tornadoes. Lightning is the most common danger associated with thunderstorms. As soon as you see lightning or hear thunder, you should find shelter inside a building or vehicle with the windows closed.

Protect yourself from severe thunderstorms:

About tornadoes

Tornadoes can produce some of the highest wind speeds on the planet. Most Canadian tornadoes have maximum wind speeds under 180 km/h, but they can still cause serious damage. 

When a tornado threatens, take shelter immediately, preferably in the lower level of a sturdy building.

All tornado events are rated using the Enhanced Fujita scale for wind damage.

Protect yourself from tornadoes:

Thunderstorm Outlooks

Thunderstorm Outlooks give you an early heads-up when a thunderstorm is likely to develop—up to 36 hours in advance. We update Outlooks daily. Make sure to look for the time we issue the Outlook and the period it covers. The publication date and time show when we produced the map. All times on the map are local times.

A Thunderstorm Outlook is not an alert. It does not guarantee that a storm will develop, it only shows that the conditions are favourable. However, even if there is no Outlook for your area, it doesn’t guarantee no storms—thunderstorms can develop quickly!

Outlooks help you plan ahead, but no matter the forecast, always keep an eye (or ear) out for weather alerts!

Find the Thunderstorm Outlook for your area.

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2026-06-08