Environment Canada has issued rainfall warnings for most of northwestern Ontario, calling for up to 100mm of rain by tomorrow.

Meteorologists say they’re tracking a low-pressure system through the region, which is expected to bring 30 to 50mm of rain tonight, with the potential that the storm will continue into tomorrow morning with another 30 to 50mm.

Environment Canada says the storm could hit Kenora, Grassy Narrows, Whitedog, Sioux Narrows-Nestor Falls, Morson, Vermilion Bay, Dryden and Ignace areas.

Staff warn that heavy downpours can cause flash floods and washouts on roads, and residents are asked to use extreme caution on local roadways and highways during the storm.