Environment Canada meteorologists are tracking a severe thunderstorm capable of producing heavy rain in Windsor-Essex.
The line of severe thunderstorms is located from Leamington to Blenheim.
Environment Canada says that there will be heavy rainfall of up to 50 to 100 mm.
It warns that heavy rain may cause flash flooding and significant reductions to visibility.
Fast-moving and rapidly rising water can sweep vehicles away and damage infrastructure.
Environment Canada advises people to take immediate cover if a thunderstorm approaches. If outside, it says, protect yourself from flying debris and hail.