May is one of the warmer months of the year in Belleville, with average highs near 15°C and lows around 7.2°C (mean 11.1°C). It is about average for rainfall, averaging 67 mm of rainfall and 78% relative humidity across the period.
May is one of the warmer months of the year in Belleville. Across 45 years of records, the warmest May in Belleville was 1998 — when the month averaged 14.7°C — while the coldest was 2002 at 8.3°C. Typical May days reach 15°C with nights near 7.2°C. The long-term trend is warming, about 0.3°C per decade.
May is about average for rainfall in Belleville, averaging 67 mm of rainfall. The wettest May on record was 2017 with 154 mm, while the driest was 2005 at 21 mm.
Relative humidity in Belleville during May averages 78%. The most humid May was 2011 at 88%, and the least humid was 2021 at 71%.
May receives about 5.5 kWh/m²/day of solar energy in Belleville. The sunniest May was 2023 at 6.4 kWh/m²/day, and the cloudiest was 1984 at 4.3.
Average wind speed in Belleville during May is 1.8 m/s. The windiest May was 1997 at 2.4 m/s, while the calmest were 1992 and 2007 at 1.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.0°C | 10.6°C | 10.4°C | 11.8°C | 11.9°C | +0.9°C |
| Avg High | 14.9°C | 14.6°C | 14.2°C | 15.7°C | 15.8°C | +0.9°C |
| Avg Low | 7.0°C | 6.6°C | 6.7°C | 8.0°C | 8.1°C | +1.1°C |
| Avg Rain | 69 mm | 63 mm | 81 mm | 64 mm | 50 mm | -19 mm |
May temperatures in Belleville have risen by about 2°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -1.1°C (2020) to a record high of 28.2°C (2010).
Rainfall in May is about average for rainfall, averaging 67 mm, with a wettest year of 154 mm.
A good time to visit Belleville
May is a good time to visit Belleville, with days averaging 15°C and nights around 7.2°C (mean 11.1°C, warmer than Belleville's yearly average) and moderate rainfall. July and August are marginally more temperate, but May still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 14.5°C | 11.0°C | 7.5°C | 19.2°C | 3.2°C | 105 mm | 82% | 1.9 m/s | 5 |
| 2024 | 17.9°C | 14.4°C | 10.9°C | 24.1°C | 6.5°C | 49 mm | 79% | 1.6 m/s | 5.5 |
| 2023 | 15.7°C | 11.5°C | 7.2°C | 23.5°C | 2.4°C | 37 mm | 72% | 1.6 m/s | 6.4 |
| 2022 | 16.7°C | 12.8°C | 8.8°C | 23.6°C | 2.5°C | 48 mm | 76% | 1.7 m/s | 5.8 |
| 2021 | 15.6°C | 11.6°C | 7.6°C | 22.5°C | -0.7°C | 24 mm | 71% | 1.9 m/s | 5.9 |
| 2020 | 14.2°C | 10.4°C | 6.7°C | 24.2°C | -1.1°C | 36 mm | 75% | 2 m/s | 5.8 |
| 2019 | 12.4°C | 9.0°C | 5.7°C | 17.1°C | 2.5°C | 86 mm | 85% | 1.8 m/s | 4.8 |
| 2018 | 16.4°C | 12.2°C | 8.1°C | 21.5°C | 2.5°C | 53 mm | 82% | 1.7 m/s | 6 |
| 2017 🌧️ | 13.4°C | 10.3°C | 7.3°C | 20.1°C | 1.3°C | 154 mm | 85% | 2 m/s | 4.7 |
| 2016 | 15.9°C | 11.9°C | 7.9°C | 24.2°C | 2.4°C | 28 mm | 77% | 1.7 m/s | 6.1 |
| 2015 | 17.3°C | 12.8°C | 8.4°C | 21.9°C | 2.3°C | 39 mm | 72% | 1.9 m/s | 5.9 |
| 2014 | 14.7°C | 10.9°C | 7.1°C | 19.5°C | 2.3°C | 72 mm | 82% | 1.8 m/s | 5.5 |
| 2013 | 16.2°C | 12.3°C | 8.4°C | 23.5°C | 1.7°C | 45 mm | 75% | 1.9 m/s | 6 |
| 2012 | 18.5°C | 14.5°C | 10.5°C | 23.9°C | 4.9°C | 33 mm | 74% | 1.5 m/s | 5.9 |
| 2011 | 14.3°C | 10.9°C | 7.6°C | 20.6°C | 3.4°C | 84 mm | 88% | 1.7 m/s | 4.6 |
| 2010 | 17.5°C | 13.5°C | 9.4°C | 28.2°C | 0.8°C | 47 mm | 76% | 1.7 m/s | 5.9 |
| 2009 | 14.2°C | 10.4°C | 6.5°C | 17.8°C | 1.9°C | 81 mm | 78% | 2 m/s | 5.6 |
| 2008 | 13.2°C | 9.6°C | 5.9°C | 17.6°C | 3.4°C | 70 mm | 79% | 2 m/s | 5.7 |
| 2007 | 15.3°C | 10.9°C | 6.4°C | 22.1°C | 2.2°C | 48 mm | 76% | 1.4 m/s | 6.1 |
| 2006 | 15.8°C | 12.2°C | 8.6°C | 25.5°C | 2.3°C | 66 mm | 80% | 1.9 m/s | 5.4 |
| 2005 | 14.0°C | 10.0°C | 6.1°C | 20.9°C | 0.4°C | 21 mm | 77% | 1.7 m/s | 5.8 |
| 2004 | 14.6°C | 11.0°C | 7.4°C | 20.5°C | 1.3°C | 111 mm | 86% | 1.7 m/s | 5 |
| 2003 | 13.0°C | 9.6°C | 6.1°C | 16.4°C | 0.6°C | 113 mm | 83% | 1.7 m/s | 4.9 |
| 2002 ❄️ | 12.0°C | 8.3°C | 4.6°C | 19.2°C | 0.8°C | 118 mm | 80% | 2.3 m/s | 5.4 |
| 2001 | 15.1°C | 11.2°C | 7.3°C | 19.4°C | 2.7°C | 71 mm | 81% | 1.7 m/s | 5.4 |
| 2000 | 14.7°C | 11.2°C | 7.7°C | 19.0°C | 3.7°C | 112 mm | 85% | 2 m/s | 4.9 |
| 1999 | 16.7°C | 12.6°C | 8.5°C | 22.1°C | 4.0°C | 49 mm | 74% | 1.7 m/s | 6.1 |
| 1998 🔥 | 18.7°C | 14.7°C | 10.8°C | 23.7°C | 7.0°C | 47 mm | 76% | 1.7 m/s | 5.9 |
| 1997 | 12.1°C | 8.4°C | 4.6°C | 17.4°C | 0.0°C | 44 mm | 76% | 2.4 m/s | 5.1 |
| 1996 | 12.6°C | 8.7°C | 4.9°C | 17.5°C | 0.2°C | 63 mm | 77% | 1.7 m/s | 5.7 |
| 1995 | 15.1°C | 10.8°C | 6.5°C | 21.0°C | -0.3°C | 55 mm | 73% | 1.9 m/s | 5.3 |
| 1994 | 13.2°C | 9.0°C | 4.8°C | 21.8°C | 1.0°C | 74 mm | 78% | 1.9 m/s | 5.2 |
| 1993 | 14.1°C | 10.1°C | 6.0°C | 20.1°C | 1.9°C | 48 mm | 77% | 1.8 m/s | 5.2 |
| 1992 | 14.1°C | 9.9°C | 5.7°C | 18.7°C | 1.5°C | 71 mm | 78% | 1.4 m/s | 6 |
| 1991 | 16.9°C | 12.8°C | 8.8°C | 24.7°C | 0.8°C | 70 mm | 81% | 1.8 m/s | 5.6 |
| 1990 | 12.7°C | 9.1°C | 5.5°C | 17.8°C | 0.3°C | 111 mm | 80% | 2 m/s | 4.9 |
| 1989 | 14.5°C | 10.8°C | 7.1°C | 21.6°C | 1.9°C | 80 mm | 80% | 1.8 m/s | 4.8 |
| 1988 | 16.3°C | 11.8°C | 7.2°C | 24.9°C | 2.6°C | 56 mm | 74% | 1.6 m/s | 5.5 |
| 1987 | 16.9°C | 12.5°C | 8.1°C | 25.3°C | 1.2°C | 26 mm | 74% | 2 m/s | 5.8 |
| 1986 | 16.0°C | 12.2°C | 8.4°C | 23.5°C | -0.9°C | 69 mm | 78% | 2 m/s | 5.4 |
| 1985 | 15.5°C | 11.5°C | 7.5°C | 20.4°C | 0.4°C | 66 mm | 76% | 1.9 m/s | 5.6 |
| 1984 | 11.8°C | 8.6°C | 5.3°C | 19.5°C | 1.3°C | 85 mm | 83% | 2.2 m/s | 4.3 |
| 1983 | 12.9°C | 9.2°C | 5.6°C | 17.4°C | 0.0°C | 96 mm | 81% | 2 m/s | — |
| 1982 | 15.8°C | 11.9°C | 7.9°C | 20.2°C | 3.9°C | 67 mm | 81% | 1.5 m/s | — |
| 1981 | 14.7°C | 10.4°C | 6.1°C | 21.6°C | -0.1°C | 73 mm | 77% | 1.6 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 15°C with lows near 7.2°C (mean 11.1°C), based on 45 years of NASA POWER data.
May averages 67 mm of rainfall in Belleville, about average for rainfall. The wettest on record was 154 mm in 2017.
The hottest May reached 28.2°C in 2010. The coldest dipped to -1.1°C in 2020.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 2°C. Daytime highs moved from 14.1°C to 16.1°C and overnight lows from 6.5°C to 8.4°C over the same span.
May is one of the warmer months of the year in Belleville and about average for rainfall, so plan for around 15°C daytime highs and 7.2°C at night.
Not quite — May is the 8th coolest month in Belleville, averaging 11.1°C.
For May in Belleville, pack warm layers and a jacket for chilly mornings, with typical highs of 15°C and lows of 7.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 78% — quite humid.
Average wind speed in May is 1.8 m/s. The windiest May on record averaged 2.4 m/s (1997).
The wettest May on record was 2017 with 154 mm. On average, May sees 67 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Belleville behaves each May, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for May specifically, along with year-by-year records and how the month has changed over the decades.
