May is close to Cape Breton's year-round average, with average highs near 10.2°C and lows around 3.6°C (mean 6.9°C). It is one of the drier months, averaging 79 mm of rainfall and 85% relative humidity across the period.
May is close to Cape Breton's year-round average. Across 45 years of records, the warmest May in Cape Breton was 1999 — when the month averaged 9.9°C — while the coldest was 2019 at 5.2°C. Typical May days reach 10.2°C with nights near 3.6°C. The long-term May temperature trend is broadly flat.
May is one of the drier months in Cape Breton, averaging 79 mm of rainfall. The wettest May on record was 2017 with 179 mm, while the driest was 1987 at 30 mm.
Relative humidity in Cape Breton during May averages 85%. The most humid May was 2011 at 92%, and the least humid was 1991 at 79%.
May receives about 5.1 kWh/m²/day of solar energy in Cape Breton. The sunniest May was 1987 at 6 kWh/m²/day, and the cloudiest was 2011 at 4.
Average wind speed in Cape Breton during May is 5.4 m/s. The windiest May was 2020 at 6.5 m/s, while the calmest was 2014 at 4.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.2°C | 6.6°C | 6.8°C | 7.1°C | 7.0°C | -0.2°C |
| Avg High | 10.5°C | 10.2°C | 10.0°C | 10.3°C | 10.3°C | -0.2°C |
| Avg Low | 3.9°C | 3.1°C | 3.5°C | 3.9°C | 3.6°C | -0.3°C |
| Avg Rain | 82 mm | 66 mm | 85 mm | 90 mm | 63 mm | -20 mm |
May temperatures in Cape Breton have stayed relatively stable across the record.
May has ranged from a record low of -3.2°C (1993) to a record high of 22.4°C (2020).
Rainfall in May is one of the drier months, averaging 79 mm, with a wettest year of 179 mm.
A good time to visit Cape Breton
May is a good time to visit Cape Breton, with days averaging 10.2°C and nights around 3.6°C (mean 6.9°C, close to Cape Breton's yearly average) and moderate rainfall. August and July 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 | 10.6°C | 7.3°C | 4.0°C | 22.4°C | 0.1°C | 55 mm | 85% | 5.3 m/s | 5.2 |
| 2024 | 10.3°C | 7.4°C | 4.4°C | 18.3°C | 1.1°C | 61 mm | 90% | 4.5 m/s | 5.2 |
| 2023 | 9.9°C | 6.3°C | 2.8°C | 20.7°C | -0.5°C | 79 mm | 82% | 6.3 m/s | 5.4 |
| 2022 | 10.7°C | 7.3°C | 3.9°C | 18.7°C | -1.5°C | 47 mm | 84% | 4.9 m/s | 5.7 |
| 2021 | 9.7°C | 6.7°C | 3.6°C | 16.8°C | 1.4°C | 57 mm | 84% | 5.6 m/s | 5.4 |
| 2020 | 10.3°C | 6.7°C | 3.1°C | 22.4°C | -0.3°C | 77 mm | 82% | 6.5 m/s | 5.2 |
| 2019 ❄️ | 8.2°C | 5.2°C | 2.2°C | 13.6°C | -0.6°C | 92 mm | 85% | 5 m/s | 5.1 |
| 2018 | 10.8°C | 6.8°C | 2.8°C | 16.0°C | 0.1°C | 82 mm | 81% | 5.5 m/s | 5.7 |
| 2017 🌧️ | 9.1°C | 6.4°C | 3.7°C | 20.7°C | 1.1°C | 179 mm | 88% | 6.3 m/s | 4.9 |
| 2016 | 11.1°C | 7.8°C | 4.6°C | 19.9°C | 0.5°C | 74 mm | 87% | 4.8 m/s | 4.9 |
| 2015 | 11.4°C | 7.4°C | 3.4°C | 17.5°C | -0.7°C | 53 mm | 83% | 5.3 m/s | 5.5 |
| 2014 | 9.5°C | 6.1°C | 2.7°C | 20.0°C | -1.6°C | 82 mm | 86% | 4.1 m/s | 5 |
| 2013 | 11.0°C | 7.8°C | 4.6°C | 20.7°C | 0.6°C | 96 mm | 89% | 5.9 m/s | 4.9 |
| 2012 | 11.7°C | 8.7°C | 5.8°C | 18.2°C | 0.1°C | 72 mm | 84% | 5.1 m/s | 5.3 |
| 2011 | 9.6°C | 7.3°C | 5.1°C | 18.9°C | 1.5°C | 98 mm | 92% | 6.1 m/s | 4 |
| 2010 | 10.7°C | 7.5°C | 4.4°C | 18.2°C | 1.9°C | 73 mm | 83% | 6.3 m/s | 5.1 |
| 2009 | 11.2°C | 7.6°C | 4.0°C | 19.2°C | 0.0°C | 79 mm | 85% | 5.2 m/s | 5.2 |
| 2008 | 9.2°C | 6.2°C | 3.3°C | 13.6°C | 0.5°C | 146 mm | 89% | 6.1 m/s | 4.7 |
| 2007 | 10.1°C | 6.6°C | 3.1°C | 18.7°C | -0.3°C | 60 mm | 83% | 5.1 m/s | 4.7 |
| 2006 | 12.2°C | 8.6°C | 5.0°C | 19.9°C | 1.9°C | 95 mm | 85% | 4.6 m/s | 5.5 |
| 2005 | 8.9°C | 6.1°C | 3.2°C | 15.0°C | 0.1°C | 75 mm | 87% | 4.9 m/s | 4.9 |
| 2004 | 9.0°C | 5.9°C | 2.8°C | 13.9°C | 0.3°C | 44 mm | 82% | 5.7 m/s | 4.8 |
| 2003 | 10.1°C | 6.7°C | 3.4°C | 17.8°C | -0.9°C | 126 mm | 86% | 4.2 m/s | 5 |
| 2002 | 10.4°C | 6.7°C | 3.0°C | 16.5°C | -0.5°C | 74 mm | 82% | 6.1 m/s | 5.8 |
| 2001 | 10.1°C | 6.9°C | 3.8°C | 18.7°C | -2.2°C | 62 mm | 85% | 4.9 m/s | 5.5 |
| 2000 | 9.2°C | 6.3°C | 3.4°C | 15.5°C | -1.0°C | 90 mm | 84% | 5.4 m/s | 5 |
| 1999 🔥 | 14.2°C | 9.9°C | 5.6°C | 21.9°C | -0.4°C | 68 mm | 82% | 4.4 m/s | 5.9 |
| 1998 | 11.7°C | 8.2°C | 4.7°C | 19.0°C | 1.2°C | 105 mm | 85% | 4.9 m/s | 5.7 |
| 1997 | 8.8°C | 5.5°C | 2.2°C | 13.7°C | -1.1°C | 92 mm | 87% | 6 m/s | 4.7 |
| 1996 | 9.1°C | 5.9°C | 2.7°C | 14.4°C | -1.1°C | 47 mm | 82% | 5.5 m/s | 4.5 |
| 1995 | 9.6°C | 6.0°C | 2.4°C | 15.6°C | -2.1°C | 33 mm | 82% | 4.6 m/s | 5.4 |
| 1994 | 9.2°C | 6.0°C | 2.8°C | 15.6°C | -0.4°C | 130 mm | 87% | 6.2 m/s | 4.8 |
| 1993 | 10.1°C | 6.6°C | 3.0°C | 19.7°C | -3.2°C | 44 mm | 86% | 4.9 m/s | 4.4 |
| 1992 | 10.0°C | 6.1°C | 2.2°C | 21.9°C | -1.7°C | 31 mm | 83% | 5 m/s | 5.4 |
| 1991 | 10.4°C | 6.5°C | 2.6°C | 20.3°C | -2.1°C | 33 mm | 79% | 5.9 m/s | 5.2 |
| 1990 | 8.6°C | 5.6°C | 2.6°C | 18.6°C | 0.2°C | 80 mm | 84% | 6.1 m/s | 4.7 |
| 1989 | 11.4°C | 8.0°C | 4.6°C | 18.5°C | 1.5°C | 38 mm | 90% | 4.9 m/s | 4.9 |
| 1988 | 10.7°C | 7.6°C | 4.6°C | 16.5°C | 0.3°C | 65 mm | 88% | 5.8 m/s | 5 |
| 1987 | 10.3°C | 6.6°C | 2.9°C | 18.0°C | 0.3°C | 30 mm | 82% | 5.4 m/s | 6 |
| 1986 | 10.2°C | 6.7°C | 3.2°C | 18.3°C | -0.9°C | 38 mm | 84% | 4.9 m/s | 5.8 |
| 1985 | 10.4°C | 6.4°C | 2.3°C | 18.7°C | -1.3°C | 71 mm | 84% | 5.3 m/s | 5.3 |
| 1984 | 10.2°C | 7.3°C | 4.4°C | 13.7°C | 1.0°C | 97 mm | 89% | 6 m/s | 4.2 |
| 1983 | 10.5°C | 7.6°C | 4.7°C | 15.2°C | 1.9°C | 115 mm | 89% | 5.6 m/s | — |
| 1982 | 9.8°C | 6.8°C | 3.8°C | 18.7°C | 0.9°C | 114 mm | 87% | 5.5 m/s | — |
| 1981 | 10.6°C | 7.6°C | 4.5°C | 18.2°C | 0.7°C | 173 mm | 91% | 5.3 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 10.2°C with lows near 3.6°C (mean 6.9°C), based on 45 years of NASA POWER data.
May averages 79 mm of rainfall in Cape Breton, one of the drier months. The wettest on record was 179 mm in 2017.
The hottest May reached 22.4°C in 2020. The coldest dipped to -3.2°C in 1993.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have fallen by about 0.1°C. Daytime highs moved from 10.3°C to 10.2°C and overnight lows from 3.9°C to 3.7°C over the same span.
May is close to Cape Breton's year-round average and one of the drier months, so plan for around 10.2°C daytime highs and 3.6°C at night.
Not quite — May is the 7th coolest month in Cape Breton, averaging 6.9°C.
For May in Cape Breton, pack warm layers and a jacket for chilly mornings, with typical highs of 10.2°C and lows of 3.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 85% — quite humid.
Average wind speed in May is 5.4 m/s. The windiest May on record averaged 6.5 m/s (2020).
The wettest May on record was 2017 with 179 mm. On average, May sees 79 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 Cape Breton 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.
