May is one of the warmer months of the year in Nelson, with average highs near 13.5°C and lows around 2.2°C (mean 7.9°C). It is about average for rainfall, averaging 73 mm of rainfall and 70% relative humidity across the period.
May is one of the warmer months of the year in Nelson. Across 45 years of records, the warmest May in Nelson was 2023 — when the month averaged 12.7°C — while the coldest was 1984 at 4.4°C. Typical May days reach 13.5°C with nights near 2.2°C. The long-term trend is warming, about 0.2°C per decade.
May is about average for rainfall in Nelson, averaging 73 mm of rainfall. The wettest May on record was 1996 with 140 mm, while the driest was 1995 at 27 mm.
Relative humidity in Nelson during May averages 70%. The most humid May was 1996 at 80%, and the least humid was 2001 at 59%.
May receives about 5.2 kWh/m²/day of solar energy in Nelson. The sunniest Mays were 1995 and 2015 at 6 kWh/m²/day, and the cloudiest was 2022 at 4.
Average wind speed in Nelson during May is 0.3 m/s. The windiest Mays were 1993, 1995 and 2009, among others at 0.4 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.5°C | 8.1°C | 7.6°C | 8.1°C | 8.0°C | +0.5°C |
| Avg High | 13.2°C | 13.8°C | 13.3°C | 13.8°C | 13.7°C | +0.5°C |
| Avg Low | 1.9°C | 2.4°C | 2.0°C | 2.5°C | 2.4°C | +0.5°C |
| Avg Rain | 65 mm | 79 mm | 63 mm | 77 mm | 86 mm | +22 mm |
May temperatures in Nelson have risen by about 1.1°C between 1981–1985 and 2021–2025.
May has ranged from a record low of -8.1°C (1982) to a record high of 28.8°C (1983).
Rainfall in May is about average for rainfall, averaging 73 mm, with a wettest year of 140 mm.
A good time to visit Nelson
May is a good time to visit Nelson, with days averaging 13.5°C and nights around 2.2°C (mean 7.9°C, warmer than Nelson'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 | 14.3°C | 8.3°C | 2.3°C | 24.1°C | -4.8°C | 81 mm | 72% | 0.3 m/s | 5.6 |
| 2024 | 12.2°C | 6.5°C | 0.9°C | 21.1°C | -4.0°C | 72 mm | 76% | 0.3 m/s | 5 |
| 2023 🔥 | 18.3°C | 12.7°C | 7.1°C | 24.7°C | 2.5°C | 102 mm | 72% | 0.3 m/s | 5.6 |
| 2022 | 10.4°C | 5.6°C | 0.8°C | 15.7°C | -2.7°C | 89 mm | 77% | 0.3 m/s | 4 |
| 2021 | 13.5°C | 7.6°C | 1.6°C | 21.9°C | -4.2°C | 46 mm | 68% | 0.3 m/s | 5.5 |
| 2020 | 13.2°C | 7.5°C | 1.9°C | 22.7°C | -3.7°C | 129 mm | 75% | 0.3 m/s | 4.8 |
| 2019 | 15.1°C | 9.4°C | 3.6°C | 22.5°C | -1.9°C | 55 mm | 70% | 0.3 m/s | 5.3 |
| 2018 | 17.1°C | 11.0°C | 4.8°C | 23.5°C | -2.3°C | 54 mm | 72% | 0.3 m/s | 5.7 |
| 2017 | 14.1°C | 8.5°C | 3.0°C | 24.1°C | -2.2°C | 83 mm | 72% | 0.3 m/s | 5.4 |
| 2016 | 14.8°C | 9.0°C | 3.2°C | 21.3°C | -1.8°C | 108 mm | 72% | 0.3 m/s | 5.5 |
| 2015 | 15.6°C | 9.1°C | 2.6°C | 22.6°C | -2.9°C | 70 mm | 67% | 0.3 m/s | 6 |
| 2014 | 13.4°C | 8.1°C | 2.8°C | 19.4°C | -2.1°C | 91 mm | 71% | 0.3 m/s | 5.1 |
| 2013 | 14.7°C | 8.8°C | 2.8°C | 22.4°C | -4.0°C | 101 mm | 69% | 0.3 m/s | 5.5 |
| 2012 | 12.3°C | 6.8°C | 1.3°C | 21.4°C | -5.0°C | 51 mm | 67% | 0.3 m/s | 5.4 |
| 2011 | 10.0°C | 4.9°C | -0.1°C | 17.8°C | -7.7°C | 75 mm | 78% | 0.3 m/s | 5 |
| 2010 | 10.9°C | 5.8°C | 0.8°C | 19.2°C | -3.0°C | 82 mm | 71% | 0.3 m/s | 4.6 |
| 2009 | 13.3°C | 7.5°C | 1.7°C | 22.8°C | -3.4°C | 56 mm | 66% | 0.4 m/s | 5.6 |
| 2008 | 14.0°C | 7.9°C | 1.8°C | 23.7°C | -3.4°C | 53 mm | 70% | 0.3 m/s | 5.2 |
| 2007 | 14.2°C | 8.4°C | 2.6°C | 23.0°C | -3.0°C | 45 mm | 66% | 0.3 m/s | 5.7 |
| 2006 | 14.2°C | 8.7°C | 3.3°C | 26.0°C | -5.0°C | 74 mm | 67% | 0.3 m/s | 5.4 |
| 2005 | 14.9°C | 9.1°C | 3.2°C | 25.2°C | -2.2°C | 55 mm | 68% | 0.3 m/s | 5.3 |
| 2004 | 13.1°C | 7.6°C | 2.1°C | 20.3°C | -2.1°C | 76 mm | 71% | 0.3 m/s | 4.8 |
| 2003 | 12.0°C | 6.8°C | 1.6°C | 24.3°C | -3.2°C | 56 mm | 72% | 0.3 m/s | 4.6 |
| 2002 | 11.1°C | 5.8°C | 0.5°C | 19.5°C | -5.5°C | 100 mm | 72% | 0.3 m/s | 4.6 |
| 2001 | 14.8°C | 8.4°C | 2.0°C | 26.0°C | -4.5°C | 49 mm | 59% | 0.3 m/s | 5.8 |
| 2000 | 11.5°C | 6.2°C | 0.9°C | 18.1°C | -2.6°C | 62 mm | 71% | 0.3 m/s | 5 |
| 1999 | 11.0°C | 5.7°C | 0.4°C | 23.4°C | -3.7°C | 60 mm | 70% | 0.3 m/s | 5.1 |
| 1998 | 16.1°C | 10.1°C | 4.1°C | 21.9°C | -0.3°C | 127 mm | 70% | 0.3 m/s | 5.7 |
| 1997 | 13.7°C | 8.2°C | 2.6°C | 22.0°C | -1.9°C | 66 mm | 72% | 0.3 m/s | 5.5 |
| 1996 🌧️ | 9.4°C | 4.9°C | 0.4°C | 17.9°C | -3.6°C | 140 mm | 80% | 0.3 m/s | 4.2 |
| 1995 | 15.2°C | 8.8°C | 2.4°C | 23.8°C | -2.3°C | 27 mm | 62% | 0.4 m/s | 6 |
| 1994 | 14.6°C | 8.8°C | 3.1°C | 22.8°C | -1.3°C | 62 mm | 67% | 0.3 m/s | 5 |
| 1993 | 18.1°C | 11.5°C | 4.9°C | 27.7°C | -3.2°C | 54 mm | 63% | 0.4 m/s | 5.5 |
| 1992 | 15.6°C | 9.2°C | 2.8°C | 24.4°C | -3.9°C | 29 mm | 60% | 0.4 m/s | 5.7 |
| 1991 | 12.3°C | 6.7°C | 1.2°C | 19.0°C | -2.9°C | 91 mm | 76% | 0.3 m/s | 4.7 |
| 1990 | 11.8°C | 6.9°C | 1.9°C | 20.6°C | -3.3°C | 130 mm | 75% | 0.3 m/s | 4.6 |
| 1989 | 12.8°C | 7.3°C | 1.8°C | 19.1°C | -2.2°C | 74 mm | 68% | 0.3 m/s | 4.7 |
| 1988 | 14.6°C | 8.6°C | 2.6°C | 24.7°C | -4.0°C | 49 mm | 65% | 0.3 m/s | 5.3 |
| 1987 | 15.2°C | 9.0°C | 2.8°C | 23.4°C | -3.2°C | 74 mm | 65% | 0.3 m/s | 5.2 |
| 1986 | 13.4°C | 7.9°C | 2.3°C | 27.5°C | -4.7°C | 60 mm | 71% | 0.3 m/s | 5.1 |
| 1985 | 15.0°C | 9.0°C | 3.0°C | 23.0°C | -4.7°C | 42 mm | 66% | 0.3 m/s | 5.5 |
| 1984 ❄️ | 9.4°C | 4.4°C | -0.6°C | 21.0°C | -3.3°C | 85 mm | 77% | 0.3 m/s | 4.7 |
| 1983 | 14.8°C | 8.9°C | 2.9°C | 28.8°C | -2.8°C | 35 mm | 66% | 0.4 m/s | — |
| 1982 | 11.0°C | 5.4°C | -0.2°C | 21.4°C | -8.1°C | 47 mm | 73% | 0.4 m/s | — |
| 1981 | 12.3°C | 7.2°C | 2.2°C | 19.9°C | -2.4°C | 115 mm | 76% | 0.3 m/s | — |
Actual recorded May data for each year, 1981–2025 — sourced from NASA POWER.
The average high in May is around 13.5°C with lows near 2.2°C (mean 7.9°C), based on 45 years of NASA POWER data.
May averages 73 mm of rainfall in Nelson, about average for rainfall. The wettest on record was 140 mm in 1996.
The hottest May reached 28.8°C in 1983. The coldest dipped to -8.1°C in 1982.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average May temperatures have risen by about 1.1°C. Daytime highs moved from 12.5°C to 13.7°C and overnight lows from 1.5°C to 2.5°C over the same span.
May is one of the warmer months of the year in Nelson and about average for rainfall, so plan for around 13.5°C daytime highs and 2.2°C at night.
Not quite — May is the 8th coolest month in Nelson, averaging 7.9°C.
For May in Nelson, pack warm layers and a jacket for chilly mornings, with typical highs of 13.5°C and lows of 2.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in May averages 70% — moderately humid.
Average wind speed in May is 0.3 m/s. The windiest May on record averaged 0.4 m/s (1982).
The wettest May on record was 1996 with 140 mm. On average, May sees 73 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 Nelson 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.
