Sarnia-Lambton could be drenched by up to two inches of rain by Saturday morning.
Environment Canada issued a special weather statement advising of heavy rain for parts of southwestern Ontario. However, the advisory was upgraded to a rainfall warning Friday night.
The national weather agency said an area of showers and possible thunderstorms could last into Saturday afternoon.
Total rainfall amounts between 40 and 60 millimetres, may be possible with the potential for even higher amounts in thunderstorms.
Environment Canada ended the rainfall warning Saturday, shortly after 10 a.m.
