Much of southwestern Ontario is in for a soaking.
Environment Canada issued a special weather statement Wednesday for Windsor-Essex, Chatham-Kent, Sarnia-Lambton, London-Middlesex, Elgin County, and Oxford County.
The weather agency warns heavy rainfall is expected to begin in the evening and last into Thursday morning. There is also a risk of thunderstorms and strong wind gusts alongside the rainfall
Early Wednesday evening, a severe thunderstorm watch was issued for parts of Windsor-Essex and Chatham-Kent. At around 9:30 p.m., the thunderstorm watch for those regions was changed over to a tornado watch.
"Conditions are favourable for the development of severe thunderstorms which may produce a tornado. Strong wind gusts and heavy rain are also possible," read a statement from Environment Canada.
Some areas could see 30 to 50 mm of accumulation, with isolated spots potentially seeing as much as 100 mm.
More specific rainfall warnings may be issued as necessary, Environment Canada said.