Environment Canada is predicting "a soaker on tap" in Ottawa-Gatineau Monday as a cold front moves through southern and eastern Ontario.
Rainfall amounts of 15 to 25 mm are expected for the region, as well as Algonquin Park, Cornwall, Belleville, Bancroft, Haliburton and other communities.
A weather statement posted on Environment Canada's website said there's also the small chance of a thunderstorm, especially in eastern Ontario, which could bring rainfall totals anywhere from 25 to 40 mm.
The rain is expected to end by midnight.
In Ottawa, the high should reach about 19 C with showers beginning in the morning and ending late in the evening, with a low of 4 C overnight. Wind gusts anywhere from 30 km/h to 50 km/h are expected in the early afternoon.