December is one of the cooler months of the year in Nelson, with average highs near 5.8°C and lows around 2°C (mean 3.9°C). It is a relatively wet time of year, averaging 118 mm of rainfall and 95% relative humidity across the period.
December is one of the cooler months of the year in Nelson. Across 45 years of records, the warmest December in Nelson was 2015 — when the month averaged 7.3°C — while the coldest was 1981 at -1.2°C. Typical December days reach 5.8°C with nights near 2°C. The long-term trend is warming, about 0.4°C per decade.
December is a relatively wet time of year in Nelson, averaging 118 mm of rainfall. The wettest December on record was 2015 with 247 mm, while the driest was 2010 at 37 mm.
Relative humidity in Nelson during December averages 95%. The most humid December was 2010 at 97%, and the least humid was 2011 at 93%.
December receives about 0.5 kWh/m²/day of solar energy in Nelson. The sunniest Decembers were 2008, 2010 and 2022, among others at 0.6 kWh/m²/day, and the cloudiest were 2011, 2015 and 2021, among others at 0.4.
Average wind speed in Nelson during December is 4 m/s. The windiest December was 2015 at 5.5 m/s, while the calmest was 2010 at 2.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 3.6°C | 3.3°C | 3.8°C | 4.4°C | 4.8°C | +1.2°C |
| Avg High | 5.4°C | 5.2°C | 5.7°C | 6.2°C | 6.5°C | +1.1°C |
| Avg Low | 1.7°C | 1.4°C | 1.9°C | 2.5°C | 2.9°C | +1.2°C |
| Avg Rain | 112 mm | 118 mm | 106 mm | 123 mm | 142 mm | +30 mm |
December temperatures in Nelson have risen by about 1.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -10.2°C (1981) to a record high of 12.7°C (2025).
Rainfall in December is a relatively wet time of year, averaging 118 mm, with a wettest year of 247 mm.
A quieter season to visit Nelson
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Nelson. That said, December — with days averaging 5.8°C and nights around 2°C (mean 3.9°C) and higher rainfall (118 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 7.3°C | 5.6°C | 3.9°C | 12.7°C | -1.5°C | 159 mm | 96% | 4.2 m/s | — |
| 2024 | 7.8°C | 6.0°C | 4.1°C | 11.7°C | -0.9°C | 121 mm | 95% | 4.5 m/s | 0.5 |
| 2023 | 7.2°C | 5.4°C | 3.7°C | 11.1°C | -2.0°C | 185 mm | 95% | 5 m/s | 0.5 |
| 2022 | 4.7°C | 2.7°C | 0.7°C | 10.1°C | -5.3°C | 104 mm | 97% | 3.2 m/s | 0.6 |
| 2021 | 6.6°C | 4.8°C | 2.9°C | 11.4°C | -2.0°C | 120 mm | 96% | 3.6 m/s | 0.4 |
| 2020 | 5.6°C | 4.0°C | 2.4°C | 10.9°C | -2.0°C | 164 mm | 96% | 3.6 m/s | 0.5 |
| 2019 | 6.4°C | 4.8°C | 3.1°C | 11.2°C | -1.6°C | 108 mm | 96% | 4.1 m/s | 0.5 |
| 2018 | 7.1°C | 5.4°C | 3.7°C | 10.8°C | -1.8°C | 143 mm | 96% | 3.7 m/s | 0.5 |
| 2017 | 5.6°C | 3.8°C | 1.9°C | 11.1°C | -3.1°C | 90 mm | 96% | 3.6 m/s | 0.5 |
| 2016 | 7.2°C | 5.5°C | 3.8°C | 11.1°C | -1.1°C | 65 mm | 96% | 3.7 m/s | 0.5 |
| 2015 🔥 🌧️ | 9.4°C | 7.3°C | 5.1°C | 12.6°C | 0.3°C | 247 mm | 94% | 5.5 m/s | 0.4 |
| 2014 | 6.1°C | 4.3°C | 2.4°C | 10.6°C | -1.4°C | 101 mm | 94% | 4.4 m/s | 0.5 |
| 2013 | 7.5°C | 5.5°C | 3.4°C | 11.1°C | 1.2°C | 124 mm | 94% | 5.2 m/s | 0.5 |
| 2012 | 5.1°C | 3.2°C | 1.3°C | 10.3°C | -2.7°C | 162 mm | 96% | 4 m/s | 0.5 |
| 2011 | 6.6°C | 4.8°C | 3.0°C | 10.3°C | -1.3°C | 150 mm | 93% | 5.2 m/s | 0.4 |
| 2010 | 1.3°C | -0.9°C | -3.1°C | 6.3°C | -7.7°C | 37 mm | 97% | 2.5 m/s | 0.6 |
| 2009 | 3.9°C | 2.3°C | 0.6°C | 9.5°C | -3.3°C | 93 mm | 96% | 3.3 m/s | 0.5 |
| 2008 | 4.7°C | 2.7°C | 0.7°C | 9.8°C | -3.4°C | 90 mm | 96% | 3.2 m/s | 0.6 |
| 2007 | 5.7°C | 3.9°C | 2.0°C | 11.7°C | -3.1°C | 122 mm | 96% | 4.2 m/s | 0.5 |
| 2006 | 7.6°C | 5.7°C | 3.8°C | 11.7°C | 0.1°C | 166 mm | 94% | 4.4 m/s | 0.5 |
| 2005 | 6.1°C | 4.1°C | 2.1°C | 9.5°C | -2.3°C | 70 mm | 96% | 3.3 m/s | 0.5 |
| 2004 | 6.9°C | 4.9°C | 3.0°C | 9.9°C | -1.5°C | 81 mm | 95% | 3.9 m/s | 0.5 |
| 2003 | 5.9°C | 3.5°C | 1.2°C | 10.5°C | -3.6°C | 109 mm | 96% | 3.6 m/s | 0.5 |
| 2002 | 5.0°C | 3.6°C | 2.2°C | 9.9°C | -1.6°C | 136 mm | 96% | 3.7 m/s | 0.5 |
| 2001 | 5.5°C | 2.9°C | 0.3°C | 11.5°C | -2.8°C | 66 mm | 95% | 3.6 m/s | 0.6 |
| 2000 | 5.5°C | 4.1°C | 2.7°C | 11.6°C | -3.3°C | 124 mm | 95% | 4.3 m/s | 0.5 |
| 1999 | 5.4°C | 3.5°C | 1.5°C | 10.0°C | -4.0°C | 167 mm | 94% | 5 m/s | 0.5 |
| 1998 | 6.5°C | 4.5°C | 2.6°C | 12.1°C | -2.5°C | 100 mm | 96% | 4.2 m/s | 0.5 |
| 1997 | 6.4°C | 4.7°C | 3.1°C | 11.2°C | -2.0°C | 143 mm | 96% | 4.2 m/s | 0.4 |
| 1996 | 3.6°C | 1.8°C | 0.1°C | 8.8°C | -2.6°C | 71 mm | 96% | 3.7 m/s | 0.5 |
| 1995 | 2.8°C | 0.9°C | -1.0°C | 9.0°C | -8.1°C | 50 mm | 96% | 3.4 m/s | 0.5 |
| 1994 | 6.9°C | 4.9°C | 2.9°C | 12.4°C | -1.6°C | 163 mm | 95% | 4.8 m/s | 0.5 |
| 1993 | 5.6°C | 3.6°C | 1.6°C | 10.7°C | -3.2°C | 184 mm | 95% | 4.9 m/s | 0.4 |
| 1992 | 4.3°C | 2.5°C | 0.7°C | 10.6°C | -5.4°C | 104 mm | 96% | 3.5 m/s | 0.5 |
| 1991 | 5.6°C | 3.6°C | 1.6°C | 10.4°C | -5.0°C | 77 mm | 96% | 3.6 m/s | 0.5 |
| 1990 | 5.1°C | 3.2°C | 1.2°C | 9.6°C | -1.7°C | 127 mm | 94% | 4.3 m/s | 0.5 |
| 1989 | 4.5°C | 2.7°C | 0.9°C | 9.7°C | -2.1°C | 105 mm | 96% | 3.4 m/s | 0.5 |
| 1988 | 7.8°C | 6.0°C | 4.2°C | 10.1°C | -0.8°C | 84 mm | 96% | 4.5 m/s | 0.4 |
| 1987 | 5.8°C | 4.2°C | 2.6°C | 11.2°C | -2.9°C | 81 mm | 96% | 3.9 m/s | 0.5 |
| 1986 | 6.4°C | 4.3°C | 2.2°C | 11.9°C | -1.5°C | 188 mm | 94% | 5.1 m/s | 0.5 |
| 1985 | 6.4°C | 4.8°C | 3.2°C | 12.2°C | -5.8°C | 129 mm | 95% | 4.2 m/s | 0.5 |
| 1984 | 5.8°C | 4.1°C | 2.4°C | 10.7°C | -3.2°C | 81 mm | 95% | 3.8 m/s | 0.5 |
| 1983 | 6.3°C | 4.3°C | 2.3°C | 11.0°C | -2.4°C | 152 mm | 95% | 4.5 m/s | — |
| 1982 | 4.9°C | 2.9°C | 1.0°C | 9.5°C | -2.7°C | 123 mm | 95% | 4.2 m/s | — |
| 1981 ❄️ | 1.0°C | -1.2°C | -3.3°C | 8.7°C | -10.2°C | 61 mm | 96% | 3.1 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 5.8°C with lows near 2°C (mean 3.9°C), based on 45 years of NASA POWER data.
December averages 118 mm of rainfall in Nelson, a relatively wet time of year. The wettest on record was 247 mm in 2015.
The hottest December reached 12.7°C in 2025. The coldest dipped to -10.2°C in 1981.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.9°C. Daytime highs moved from 4.9°C to 6.7°C and overnight lows from 1.1°C to 3.1°C over the same span.
December is one of the cooler months of the year in Nelson and a relatively wet time of year, so plan for around 5.8°C daytime highs and 2°C at night.
Not quite — December is the 3rd coolest month in Nelson, averaging 3.9°C.
For December in Nelson, pack warm layers and a jacket for chilly mornings, with typical highs of 5.8°C and lows of 2°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 95% — quite humid.
Average wind speed in December is 4 m/s. The windiest December on record averaged 5.5 m/s (2015).
The wettest December on record was 2015 with 247 mm. On average, December sees 118 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 December, 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 December specifically, along with year-by-year records and how the month has changed over the decades.
