UPDATE: Severe thunderstorms, tornado watch, warning for much of southwestern Ontario

© Can Stock Photo / JakeBlaster

Environment Canada issued tornado and thunderstorm watches and warning for much of Southwestern Ontario on Wednesday signaling a potential for violent weather.

At around 6:45 p.m., a tornado watch was briefly upgraded to a warning for London-Middlesex with a highlighted risk in areas northwest of London between Nairn and Lucan. The warning was lifted less than hour later, while a tornado watch remains in place.

At 8:14 p.m. a tornado warning was put in place for St. Thomas, Aylmer and eastern Elgin County. The warning was lifted approximately 20 minutes later.

All weather watches and warnings were lifted at around 8:50 p.m. A heat warning remains in place for Thursday.

Windsor-Essex, Chatham-Kent, Sarnia-Lambton, and London-Middlesex were put under a tornado watch, just after noon.

A tornado watch means that conditions are favourable for the development of tornadoes.

Forecasters began tracking a storm system over Michigan, which started to pass through Ontario late Wednesday afternoon.