Ottawa weather
Loading live data…Clear,much the same tomorrow
Env. Canada, the European and the American model put Ottawa's high today between 21° and 25°, a 4° split. Tomorrow looks cloudy around 24°, with a 15% chance of rain.
The weather map: all three models at once
Env. Canada, European, American side by side around Ottawa and nearby towns.Live rain radar →Next 14 hours
consensus of the three models14-day forecast
where the models agree, and where they splitOttawa, Ontario. Below we compare what Env. Canada, European, American forecast for Ottawa right now and flag exactly where they disagree, then break down Ottawa's weather month by month and which forecast model has been most accurate here.
We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in Canada before you trust any single number.
Ottawa weather by month
what to expect in Ottawa through the yearHere is Ottawa's typical weather in each month: the average daytime high and overnight low in °C, how each month feels, and the wettest month marked. Use it to plan any trip to Ottawa by season.
What Ottawa's weather is like through the year
Ottawa runs from warm summers, with July highs near 26°C, to cold winters, when February lows sit around -11°C (a swing of about 37°C across the year). August is usually the wettest month, and Ottawa sees roughly 1154 mm of precipitation annually. Overnight lows stay below freezing across 4 months (January, February, March and December), so Ottawa sees regular winter snowfall.
Best time to visit Ottawa
The most comfortable time to visit Ottawa is usually May, June, July and September, when daytime highs sit in the pleasant 16-26°C range and the heaviest August rain is behind you.
Which forecast is most accurate in Ottawa?
CheckWeather Score — graded against the weather that actually happened
The CheckWeather Score blends temperature, wind and rain accuracy — each measured against ERA5 (the recorded weather) over the last 30 days across 1302 cities. Lower error means a higher score. See which forecast model is most accurate in Canada, how we measure forecast accuracy, or which model each weather app uses.
Bottom line: over the last 30 days the European model has been the most accurate forecast for Ottawa, scoring 93/100 on our CheckWeather Score, ahead of the Env. Canada at 81. See the full CA accuracy scoreboard for exactly how every model is tested.
Where the models disagree
temperature and rain, judged separatelyThe models often agree on temperature and still split on rain — and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.