Tornado Risk Rises in Ontario as Severe Storms Approach
A significant weather event is expected to unfold across Ontario on Wednesday, June 18, 2025, as a low-pressure system surges north from the United States. Meteorologists are warning of a dangerous combination of weather factors that could lead to tornadoes, damaging winds, and large hail — especially in southwestern regions of the province.
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Environment Canada Monitoring for Potential Tornado Warnings
Environment and Climate Change Canada is closely watching conditions that could lead to severe thunderstorms and tornadoes across Ontario. A severe thunderstorm watch has already been issued for Timmins in northern Ontario, and the threat is expected to expand southward into heavily populated areas.
Steven Flisfeder, a meteorologist with the federal weather agency, confirmed that Wednesday will bring elevated risks for severe storms in southwestern Ontario, including areas from Sarnia across to Lake Erie, where the greatest risk for tornado development currently lies.
What to Expect from the Storm System
The low-pressure system is forecast to enter Ontario in the early morning hours, with storms beginning to impact southern Ontario between 9 a.m. and 11 a.m. The system will bring:
- Straight-line winds gusting up to 90 km/h
- Hail ranging from 2 to 3 centimetres
- Torrential rainfall in some areas
- A high potential for tornadoes, depending on how wind patterns align in the atmosphere
The heat and moisture currently present across the region are key ingredients for tornado formation, coupled with atmospheric wind shifts.
Severe Thunderstorm Warning Issued For Calgary, Alberta: Hail, Strong Winds Expected
Alert Systems and Warnings
While residents may be anticipating an Alert Ready notification, Environment Canada clarifies that these are only issued for extreme events — such as tornadoes, hail over 7 cm, or winds exceeding 130 km/h. Therefore, not all warnings on Wednesday will trigger an emergency alert to your phone.
Still, residents are advised to stay alert and check for local updates frequently throughout the day.
Outdoor Activities: Reschedule if Possible
“If you can postpone outdoor activity, it’s best to do that until there’s a clear day in the forecast,” said Flisfeder.
While Wednesday may not be a complete washout, the risk of fast-developing, dangerous weather means outdoor plans could turn risky at a moment’s notice.
Final Warning from Meteorologists
As the situation continues to evolve overnight, Environment Canada urges residents to monitor local forecasts and have a severe weather plan in place. Tornadoes may not strike everywhere, but the potential is real — and preparation could make all the difference.
