Environment Canada has issued a severe thunderstorm watch for Waterloo Region, Guelph and Wellington County because of scattered storms forecasted for Tuesday evening.
The weather office says thunderstorms will develop off of Lake Huron and then move southeast to the western GTA area.
There is also a potential of wind gusts of up to 100 km/h and brief torrential downpours with lightning, Environment Canada said.
It added that large hail and even an isolated tornado are also possible.
The storm is expected to be localized and some places will not be affected but the severe weather should end at around midnight.
The weather office reminded residents that large hail and strong wind can cause property damage.
Residents are being urged to head indoors when severe weather approaches.
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