Severe thunderstorm watch issued for parts of southwestern Ontario

Thunderstorm Summer Thunderstorm Flash

Environment Canada has issued a severe thunderstorm watch for parts of southwestern Ontario, including Stratford, Woodstock, Brantford, Norfolk and Haldimand counties.

The weather agency said conditions are “favourable” for the development of thunderstorms capable of producing strong wind gusts, large hail and heavy rain.

The system is expected to move into the region early Tuesday morning, with storms over lower Michigan forecast to cross the border around 6 a.m. and track eastward.

Environment Canada warned the storms may bring hail up to the size of a toonie, torrential downpours and frequent lightning.

“Emergency Management Ontario recommends that you take cover immediately if threatening weather approaches,” the advisory read in part. “Heavy rain can cause flash flooding and significant reductions to visibility.”

Drivers are being advised to use caution as conditions may deteriorate quickly.