Shelf cloud rolling in, June 18, 2014. (Photo courtesy of Melanie Roberts via the Blackburn Radio app)Shelf cloud rolling in, June 18, 2014. (Photo courtesy of Melanie Roberts via the Blackburn Radio app)
London

UPDATE: Severe thunderstorms possible Friday

Residents in southwestern Ontario could see strong thunderstorms as they kick off the long weekend.

Environment Canada issued thunderstorm watches for Sarnia, London, Middlesex County, Huron-Perth, Chatham-Kent and Windsor-Essex. Throughout Friday the warnings were upgraded to warnings during the day before downgrading again to watches by the evening and eventually ending altogether by Friday night.

The weather agency says conditions very heavy local downpours giving rainfall amounts of 20 to 40 mm. A few wind gusts to 70 km/h are possible. "The showers and thunderstorms will move to the southeast of the area after midnight," Environment Canada said in the weather advisory.

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