Ottawa, Canada Climate & Monthly Averages
The climate of 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).
Climate 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.
How Ottawa compares
- Ottawa averages 45°F (7°C) across the year - cooler than all but 4% of the 3496 cities we track.
Ranked against every city in our dataset, each measured on the same ten-year window.
Monthly climate table
| 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% |
Ottawa month by month
Ottawa weather in January
January brings highs around 25°F (-4°C), lows near 8°F (-13°C), about 11 wet days and roughly 8 snowy days - typically the coldest month of the year in Ottawa.
Ottawa weather in February
February brings highs around 28°F (-2°C), lows near 9°F (-13°C), about 12 wet days and roughly 8 snowy days - typically the driest month of the year in Ottawa.
Ottawa weather in March
March brings highs around 37°F (3°C), lows near 20°F (-7°C), about 11 wet days and roughly 5 snowy days.
Ottawa weather in April
April brings highs around 51°F (11°C), lows near 32°F (0°C), about 13 wet days and roughly 2 snowy days.
Ottawa weather in May
May brings highs around 67°F (19°C), lows near 46°F (8°C), about 11 wet days.
Ottawa weather in June
June brings highs around 74°F (23°C), lows near 56°F (13°C), about 13 wet days.
Ottawa weather in July
July brings highs around 80°F (27°C), lows near 63°F (17°C), about 13 wet days - typically the hottest month and the sunniest month of the year in Ottawa.
Ottawa weather in August
August brings highs around 77°F (25°C), lows near 62°F (17°C), about 13 wet days - typically the wettest month of the year in Ottawa.
Ottawa weather in September
September brings highs around 71°F (22°C), lows near 55°F (13°C), about 9 wet days.
Ottawa weather in October
October brings highs around 57°F (14°C), lows near 44°F (7°C), about 12 wet days.
Ottawa weather in November
November brings highs around 43°F (6°C), lows near 31°F (-1°C), about 12 wet days and roughly 3 snowy days.
Ottawa weather in December
December brings highs around 32°F (0°C), lows near 20°F (-7°C), about 12 wet days and roughly 7 snowy days.
Seasons in Ottawa
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.
Climate questions, answered
How warm is Ottawa on average?
Is Ottawa warmer or cooler than most cities?
Is Ottawa humid?
What should I wear in Ottawa?
Best time to visit Ottawa
The best time to visit Ottawa is generally May to October, when these are the warmest and brightest weeks of the year. Daytime temperatures in that window sit near 71°F (22°C), with rain on about 12 days a month. For the same question asked the other way round, see where else is warm in May.
Pack for Ottawa with a heavy insulated coat, hat and gloves for winter and proper waterproofs rather than an umbrella - wet days are the norm here. Even in July, lows of 63°F (17°C) make an extra layer worth the space.
Ottawa temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.