Flash flooding risk in Ontario, Quebec as remnants of tropical storm Debby on the way

Up to 100 millimetres of rain is forecast to hit parts of Eastern Canada by the weekend as the remnants of tropical storm Debby make their way to the region.

Environment Canada is warning of heavy rain and risks of flash flooding and sewer backups across a swath of the country from Cornwall, Ont., to Quebec City.

Meteorologist Jennifer Smith told a news conference that a low-pressure system over the Great Lakes will bring rain and possible thunderstorms in Eastern Ontario and southern Quebec tonight before the weather system merges with what's left of Debby.

Smith says Montreal receives an average of 94 mm of rain for August, but the city is expected to see 60 to 80 mm of rain on Friday alone.

On Saturday the weather system will move northeast across eastern Quebec and northwest New Brunswick, then on to northern Newfoundland and southern Labrador on Sunday.

Smith says that parts of Eastern Canada have received "abundant" periods of heavy rain so far this season, which has left the soil saturated with a reduced ability to absorb water.