Ottawa weather in May
Temperature, rain and sunshine in May: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in May
Good
Best time to visit: May – September
What is the weather like in Ottawa in May?
In May, Ottawa is mild: daytime highs average 19 °C, and nights cool down to about 8 °C. The sun shines for around 7 hours a day. Rain is frequent, with about 12 rainy days and 90 mm in total. All in all, May is a good month for a holiday in Ottawa.
May compared
How the weather changes from April to June. Tap a month to open it.
More details for May
- Daylight
- 14 h 51 min05:33 – 20:24
- UV index
- 8 · very highclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 16 km/haverage daily peakAll months
- Cloud cover
- 62 %on averageAll months
- Hot days
- 1 day30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC−4America/Toronto
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %68 %
- Few rainy daysweight 30 %45 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in May
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
- Rain jacket or umbrella
Ottawa in May: quick answers
Is Ottawa hot in May?
No. In May, Ottawa is mild: daytime highs average 19 °C and nights drop to about 8 °C.
Does it rain much in Ottawa in May?
Rain is frequent, with about 12 rainy days and 90 mm in total.
Ottawa month by month
The whole year in OttawaAll destinations: CanadaWhere to go in May
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences