City break

London, Ontario weather in May

Temperature, rain and sunshine in May: long-term averages from 30 years of weather data, not a forecast.

77

Holiday weather in May

Good

Best time to visit: May – September

What is the weather like in London, Ontario in May?

In May, London, Ontario is mild: daytime highs average 19 °C, and nights cool down to about 9 °C. The sun shines for around 8 hours a day. Rain is frequent, with about 13 rainy days and 95 mm in total. All in all, May is a good month for a holiday in London, Ontario.

May compared

How the weather changes from April to June. Tap a month to open it.

AprilAprMayMayJuneJun
Score427781
Day12°19°24°
Night2°9°15°
Sun6 h8 h9 h
Rain days131312

More details for May

Daylight
14 h 37 min06:02 – 20:40
UV index
9 · very highclear sky, noon (estimate)All months
Muggy days
1 daydew point 18 °C or moreAll months
Wind
18 km/haverage daily peakAll months
Cloud cover
60 %on averageAll months
Hot days
0 days30 °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 %75 %
  • Few rainy daysweight 30 %39 %

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

London, Ontario in May: quick answers

Is London, Ontario hot in May?

No. In May, London, Ontario is mild: daytime highs average 19 °C and nights drop to about 9 °C.

Does it rain much in London, Ontario in May?

Rain is frequent, with about 13 rainy days and 95 mm in total.

London, Ontario month by month

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