Ottawa could see 30 to 40 mm of rain over the next 24 hours

Rainy day in the ByWard Market. (CTV News Ottawa)

Heavy rain is in the forecast to kickoff the final week of summer.

Environment Canada has issued a special weather statement, warning Ottawa could see 30 to 40 mm of rain today through Monday evening.

Showers, at times heavy, are expected to continue over the next 24 hours.

"Showers and thunderstorms have developed over central and eastern Ontario and are expected to continue intermittently through Monday evening," Environment Canada said in a statement. "Locally higher rainfall amounts are possible in areas that receive thunderstorms."

Environment Canada says Prescott-Russell, Brockville-Leeds and Grenville, and Renfrew-Pembroke-Barry's Bay will also see 30 to 40 mm of rain.

The forecast calls for showers to continue through the evening, with the risk of a thunderstorm. Amount 5 to 10 mm of rain. Low 13 C.

Showers will continue on Monday with a risk of a thunderstorm. Local amount 15 to 25 mm. High 18 C.

Clouds linger Tuesday with a high of 19 C.

Wednesday could see some showers and a high of 22 C.

Fall officially arrives late Thursday. The forecast includes a low chance of showers and a high of 14 C.

The normal temperatures for this time of year are a high of 19 C and a low of 9 C.