Warm weather, rain and snow in the forecast for Ottawa this weekend

Here is your full local weather forecast for Ottawa and eastern Ontario for April 18, 2026.

In terms of weather, Ottawa is due for a little bit of everything this weekend, with stretches of warm weather, rain and even snow in the forecast.

The weekend will kick-off with what should be a pleasantly warm Saturday morning.

Environment Canada’s forecast predicts a mainly cloudy day with temperatures reaching a high of 23 C before the rainfall arrives.

Special weather statement

Environment Canada issued a special weather statement for the Ottawa area, warning of another significant rainfall beginning late this afternoon and continuing into Sunday morning.

According to Environment Canada’s statement, Ottawa residents should expect 10 to 20 millimetres of rain. There is also a risk of thunderstorms.

• Hourly and 7-day forecast on our CTVNewsOttawa.ca weather hub

“Portions of the region have received significant rainfall amounts over the last few days. As a result, further rainfall could have significant impacts,” Environment Canada wrote.

“Water will likely pool on roads and in low-lying areas. Don’t drive through flooded roadways. Avoid low-lying areas.”

A flood warning is in effect along the Ottawa River from Arnprior to Pembroke, and in Gatineau, the city says nearly 120 buildings are at risk of flooding this weekend.

The temperature will drop to a low of 5 C overnight, and on Sunday morning, rain showers may mix with snow. Expect a temperature high of 6 C on Sunday.

On Monday, expect 4 C and a mix of sun and clouds.

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