Ottawa averages about -10°C in January and 21°C in July and gets roughly 2 metres of snow a winter. This page covers every month and where to find the live forecast.
Ottawa weather now and the hourly forecast
Ottawa averages about -10°C in January and 21°C in July. July highs average 27.0°C and January lows average -14.3°C. The city gets roughly 2 metres of snow a winter: 231.9 cm a year at the airport station and 184.5 cm at the city station. These are Environment Canada's 1991-2020 climate normals.
For today's conditions, use Environment Canada's Ottawa page. It shows the current reading from Ottawa Macdonald-Cartier International Airport, the 7-day forecast, today's normal high and low, any alerts, and links to radar, air quality and past data. The hourly forecast covers the next 24 hours.
Ottawa 7-day and 14-day forecast
Environment Canada does not publish a 14-day public forecast. Its location pages run 7 days. The 14-day view most people find comes from The Weather Network, which also has a 72-hour hourly view, weekend and monthly tabs, and a historical average line on its temperature chart. It does not say how accurate the later days are.
Use Environment Canada for official alerts and airport observations. Use The Weather Network when you want a look past day 7.
Ottawa weather by month: winter and spring
December averages -5.8°C, January -10.0°C and February -8.5°C. In January the high averages -5.5°C and the low -14.3°C. January has about 23.7 days that stay at or below 0°C, 17.2 days with a wind chill below -20 and 8.1 nights below -20°C.
March averages -2.4°C and still brings 38.8 cm of snow. April warms to 5.9°C with 69.6 mm of rain. May averages 13.6°C with highs near 19.6°C. The last spring frost comes around April 29 on average.
Ottawa weather by month: summer and fall
June averages 18.7°C, July 21.2°C and August 20.1°C. July highs average 27.0°C, with about 6.1 days above 30°C and 17 days with a humidex of 30 or more. June is the wettest month at 96.8 mm of rain. July has the most thunderstorm days, at 6.1.
September averages 15.3°C with highs of 21.0°C and 90.6 mm of rain. October drops to 8.2°C, and the first fall frost comes around October 7. November averages 1.7°C with 20.7 cm of snow, and the first snowfall comes around November 6.
Records for 1991-2020 at the airport: 36.9°C at the top, -33.1°C at the bottom, a humidex of 47.2 and a wind chill of -46.5. The airport's long-term records (1938-2020) are 37.8°C in August 1944 and -36.1°C in February 1943.
How much snow does Ottawa get?
About 2.3 metres a year at the airport and about 1.8 metres at the city station. January is the snowiest month at 59.2 cm, then December at 49.6 cm and February at 48.5 cm. Snow falls on about 62 days a year.
Snow on the ground peaks in February at an average depth of 30 cm. The biggest one-day snowfall in 1991-2020 was 35.6 cm on 16 December 2007, and the deepest snow on the ground was 135 cm on 14 March 1993. Freezing rain or drizzle falls on about 14 days a year, most often in January.
For yesterday's total, use the "View yesterday's weather data" link on Environment Canada's Ottawa page. For older days, use Environment Canada's Historical Climate Data search and search the station name "Ottawa". Ottawa Intl A holds airport data from 2011 on, and Ottawa Macdonald-Cartier Int'l A holds 1953 to 2011.
Ottawa weather alerts: tornado, snowfall and heat warnings
Environment Canada alerts are colour-coded. Yellow is the most common and means hazardous weather that may cause damage, disruption or health impacts. Orange is uncommon and means severe weather likely to cause significant damage, disruption or health impacts. Red is rare and means very dangerous, possibly life-threatening weather. Alerts now follow Weather Impact Guides for 14 hazards, including snow, heat, cold, ice, thunderstorms and tornadoes. The guides replace the former criteria for public weather alerts.
On 21 September 2018, two major tornadoes and four EF-1 tornadoes hit the region. The strongest, an EF-3 with winds up to 265 km/h, ran almost 40 km from Dunrobin across the Ottawa River into Mont-Bleu in Gatineau, and 430,000 people lost power. On 21 May 2022, a derecho brought a 190 km/h downburst in south Ottawa, 11 deaths and more than $1 billion in insured damage.
Kanata, Orleans and Gatineau weather, and what to do in it
Kanata has its own Environment Canada forecast page, though its current conditions come from the Ottawa airport station. Gatineau's page is listed as Pointe-Gatineau and uses Gatineau Airport observations. Environment Canada lists no 1991-2020 normals station with Gatineau in its name, so the Ottawa normals are the closest guide. For Orleans, use the Ottawa forecast.
On a cold or wet day, our ranked museums list is the easy pick. On a clear day, see the outdoors guide, or check the events calendar and things to do.
Questions and answers
How much snow did Ottawa get yesterday?
Use the "View yesterday's weather data" link on Environment Canada's Ottawa page. It reports from Ottawa Macdonald-Cartier International Airport.
How much snow does Ottawa get in a year?
About 231.9 cm at the airport and 184.5 cm at the city station, so roughly 2 metres. January is the snowiest month at 59.2 cm.
When does summer start in Ottawa?
On the 1991-2020 normals, average daily highs pass 20°C in June (24.4°C) and stay above it through September (21.0°C). The last spring frost averages April 29.
Where can I see Ottawa weather history?
Use Environment Canada's Historical Climate Data search and search the station name "Ottawa". Pick Ottawa Intl A for 2011 on, or Ottawa Macdonald-Cartier Int'l A for 1953 to 2011.
Is there a 14-day forecast for Ottawa?
Not from Environment Canada, which forecasts 7 days. The Weather Network publishes a 14-day Ottawa page but gives no accuracy note for the later days.
Sources
- Environment Canada, Canadian Climate Normals 1991-2020, Ottawa (Airport) 6106000. Checked .
- Environment Canada, Canadian Climate Normals 1991-2020, Ottawa (City) 6105976. Checked .
- Environment Canada, Climate Normals 1991-2020 station search for "gatineau". Checked .
- Environment Canada, Ottawa, ON - 7 Day Forecast. Checked .
- Environment Canada, Ottawa hourly forecast. Checked .
- Environment Canada, Kanata, ON - 7 Day Forecast. Checked .
- Environment Canada, Pointe-Gatineau, QC - 7 Day Forecast. Checked .
- Environment Canada, Historical Climate Data. Checked .
- Environment Canada, Historical Climate Data station search for "ottawa". Checked .
- The Weather Network, Ottawa 14-day forecast. Checked .
- Government of Canada, Colour-coded weather alerts. Checked .
- Government of Canada, Criteria for public weather alerts (superseded notice). Checked .
- Government of Canada, Weather Impact Guides. Checked .
- Environment and Climate Change Canada, Canada's top ten weather stories of 2018. Checked .
- Environment and Climate Change Canada, Canada's top ten weather stories of 2022. Checked .