Ottawa, Canada Weather
Ottawa hourly forecast: next 24 hours
Today's high of 80°F (27°C) is about 3°F (2°C) above the typical August high of 77°F (25°C).
Current conditions in detail
Ottawa weather tomorrow (Thursday, August 27)
Tomorrow in Ottawa looks mist, with a high of 72° and an overnight low of 59°. There is a 83% chance of rain - plan accordingly. Winds top out near 11 mph, and the UV index reaches 4 (moderate).
Ottawa 14-day forecast
About the weather in Ottawa
A 30°C spread between its warmest and coolest months puts Ottawa among the more strongly seasonal places we cover. July averages 80°F (27°C) by day; January averages 25°F (-4°C), with nights at 8°F (-13°C).
Ottawa weather: quick facts
- Hottest month: July - highs near 80°F (27°C)
- Coldest month: January - highs near 25°F (-4°C)
- Decade extremes (2015-2024): 96°F (36°C) high · -26°F (-32°C) low
- Wettest month: August (13 rainy days) · Sunniest: July (12.0 h sun/day)
- Climate type: humid continental
- Annual swing: 30°C between the average warmest and coolest month · day to night: 9°C
- Snow: about 34 days a year
- Months with freezing average lows: 5
- Average humidity: 73%
Temperatures through the year
July is the brightest month at 12.0 hours of sun a day, against an annual average of 8.0 - duller than about 83% of the cities we track. At its warmest, in July, Ottawa runs to 80°F (27°C) in the afternoon and back to 63°F (17°C) by dawn. January bottoms out at 25°F (-4°C) in daylight, 8°F (-13°C) after dark. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 96°F (36°C) and the lowest daily minimum -26°F (-32°C). Between the average July and the average January lie 30°C, a wider spread than 96% of the 3496 cities in our dataset.
Rain, sun and snow
Snow falls on roughly 34 days a year, mostly October through April. Overnight lows average at or below freezing for 5 months, November through March.
Season by season
Spring (March through May)
Spring in Ottawa stays firmly cold, with daytime highs averaging 52°F (11°C) and nights around 33°F (0°C); rain falls on around 34 of the 90 days, plus about 8 snowy days.
Summer (June through August)
Summer is mild and warm here - highs near 77°F (25°C), nights near 60°F (16°C), and rain falls on around 38 of the 90 days. Daylight is generous - around 11.2 hours of sun a day.
Fall (September through November)
Fall in Ottawa is crisp but comfortable, with daytime highs averaging 57°F (14°C) and nights around 43°F (6°C); rain falls on around 33 of the 90 days, plus about 4 snowy days.
Winter (December through February)
Winter in Ottawa is bitterly cold, with daytime highs averaging 28°F (-2°C) and nights around 12°F (-11°C); rain falls on around 35 of the 90 days, plus about 23 snowy days. Wind sharpens cold like this considerably; pair the forecast winds with the wind speed converter to judge exposed conditions.
Average temperatures in Ottawa by month
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 25° | 8° | 11 | 3.0 in | 4.9 h/day | 76% |
| February | 28° | 9° | 12 | 2.9 in | 6.1 h/day | 73% |
| March | 37° | 20° | 11 | 3.0 in | 7.5 h/day | 70% |
| April | 51° | 32° | 13 | 4.2 in | 8.2 h/day | 66% |
| May | 67° | 46° | 11 | 3.4 in | 10.4 h/day | 66% |
| June | 74° | 56° | 13 | 4.5 in | 10.8 h/day | 71% |
| July | 80° | 63° | 13 | 4.2 in | 12.0 h/day | 72% |
| August | 77° | 62° | 13 | 4.8 in | 10.8 h/day | 76% |
| September | 71° | 55° | 9 | 3.0 in | 9.5 h/day | 76% |
| October | 57° | 44° | 12 | 4.1 in | 6.4 h/day | 77% |
| November | 43° | 31° | 12 | 3.0 in | 5.0 h/day | 76% |
| December | 32° | 20° | 12 | 3.5 in | 3.8 h/day | 78% |