When it rains, it pours.

Environment Canada has issued a special weather statement for Waterloo Region and much of southern Ontario, calling for the most significant widespread rainfall we’ve seen in months.

Rainfall on Tuesday is expected to be between 25-40 mm in most places, some areas could get as much as 60 mm.

Flash flooding is possible in some areas.

A slow-moving low pressure system in the U.S. is expected to drift north over the next couple days, reaching the Great Lakes on Tuesday and taping into the same tropical moisture responsible for the floods across Louisiana.

An extreme rainfall warning has not been issued, but may be if Environment Canada predicts rainfall will be in excess of 50 mm in most areas.