A rainfall warning covers the the entire midwestern Ontario region.
That warning covers an area of Ontario stretching from Windsor east and northeast. The GTA and central areas of Ontario are under an advisory.
Environment Canada is calling for up to 100 millimetres of rain to fall by Thursday morning. The extended period of precipitation could cause flooding in low lying areas and increase the risk of hydroplaning on area roads.
People are urged to stay away from rivers and streams and to keep children and pets away as well.