Environment Canada issued the warning just after 3 p.m.  and then replaced it with a severe thunderstorm warning just before 4 p.m.
A severe tornado watch remains in effect for Gray County, the Bruce Peninsula, Tobermory, Sauble Beach, Owen Sound, Hanover, Dundalk and Kincardine.
Environment Canada has also issued a severe thunderstorm warning for some nearby communities, including Midland and Orillia.
It says heavy rain is possible in some areas with accumulation totals of up to 50mm.
“Environment Canada forecasters are monitoring a strong storm capable of producing very strong wind gusts, nickel-sized hail and torrential rain,” the warning says.