SUDBURY -- Environment Canada has issued a severe thunderstorm watch for Greater Sudbury and vicinity, North Bay, Powassan, Mattawa West Nipissing and French River.

"Conditions are favourable for the development of scattered thunderstorms this afternoon and early this evening," the weather forecaster said in a news release.

"Some of these thunderstorms may become severe with wind gusts to 90 km/h. Small hail and frequent lightning are also possible."

Residents are advised to take cover immediately if threatening weather approaches.

"Strong wind gusts can toss loose objects, damage weak buildings, break branches off trees and overturn large vehicles," the release said. "Lightning kills and injures Canadians every year. Remember, when thunder roars, go indoors."

Severe thunderstorm watches are issued when atmospheric conditions are favourable for the development of thunderstorms that could produce one or more of the following: large hail, damaging winds, torrential rainfall.

To report severe weather, send an email to or tweet reports using #ONStorm.

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