Environment Canada has issued a severe thunderstorm for London, Parkhill and eastern Middlesex County.
The national weather agency says its meteorologists are tracking a slow-moving cluster of severe thunderstorms capable of producing heavy rain.
Drivers are advised to use caution on roadways as the storms may cause reduced visibility and water pooling.
A similar warning was issued for Strathroy, Komoka and western Middlesex County, but that warning has since ended.
Forecasters are calling for Saturday morning’s rain to taper off closer to noon.