Two major systems will give heavy rain to the warned regions over the next 36 hours.
- The first is a frontal system which will lie across the area tonight into Sunday.
- The second will be the remnants of hurricane Ike, which will race across Southern Ontario late Sunday.
Southwestern Ontario is expected to receive the most extreme rainfall amounts. Rain at times heavy associated with the front will give 50 to 100 millimetres to many locales by Sunday morning. As of 8:00 p.m., Windsor had already received 57 millimetres.
The rain will taper off somewhat tonight, only to become very heavy , Sunday afternoon as Ike moves through. An additional 50 to possibly 100 millimetres are expected from Ike. As a result some places will receive as much as 150 to 200 millimetres of rain by Sunday night. Furthermore there is the additional threat for isolated thunderstorms to develop giving locally even higher amounts. For areas further northeast, including the Toronto area, about 20 to 30 millimetres is expected from the frontal system overnight into Sunday. The rain will taper off for a period during the day Sunday, to be followed by an additional 50 millimetres as torrential rain from Ike moves through Sunday evening. The heavy rain will end over all of the warned regions Sunday night. Environment Canada will continue monitor this situation closely.