December is one of the warmer months of the year in Greymouth, with average highs near 16.3°C and lows around 10.8°C (mean 13.6°C). It is a relatively wet time of year, averaging 194 mm of rainfall and 83% relative humidity across the period.
December is one of the warmer months of the year in Greymouth. Across 45 years of records, the warmest December in Greymouth was 2017 — when the month averaged 15.8°C — while the coldest was 2004 at 10.8°C. Typical December days reach 16.3°C with nights near 10.8°C. The long-term trend is warming, about 0.2°C per decade.
December is a relatively wet time of year in Greymouth, averaging 194 mm of rainfall. The wettest December on record was 1995 with 317 mm, while the driest was 1999 at 69 mm.
Relative humidity in Greymouth during December averages 83%. The most humid December was 1995 at 86%, and the least humid was 1992 at 80%.
December receives about 5.8 kWh/m²/day of solar energy in Greymouth. The sunniest December was 2017 at 7.1 kWh/m²/day, and the cloudiest was 2001 at 4.7.
Average wind speed in Greymouth during December is 1.2 m/s. The windiest December was 1990 at 1.6 m/s, while the calmest were 2017, 2018 and 2022, among others at 1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 13.7°C | 13.0°C | 13.1°C | 14.1°C | 14.3°C | +0.6°C |
| Avg High | 16.5°C | 15.7°C | 15.8°C | 17.0°C | 17.0°C | +0.5°C |
| Avg Low | 10.9°C | 10.2°C | 10.4°C | 11.2°C | 11.6°C | +0.7°C |
| Avg Rain | 211 mm | 187 mm | 187 mm | 184 mm | 207 mm | -4 mm |
December temperatures in Greymouth have risen by about 0.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 4.8°C (1993) to a record high of 22.1°C (2005).
Rainfall in December is a relatively wet time of year, averaging 194 mm, with a wettest year of 317 mm.
One of the best times to visit Greymouth
December is one of the best times to visit Greymouth. Expect days averaging 16.3°C and nights around 10.8°C (mean 13.6°C) — warmer than Greymouth's yearly average — with higher rainfall (194 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 16.1°C | 13.4°C | 10.8°C | 19.6°C | 7.9°C | 175 mm | 82% | 1.4 m/s | — |
| 2024 | 18.1°C | 15.0°C | 11.9°C | 20.8°C | 7.4°C | 239 mm | 83% | 1.1 m/s | 6.1 |
| 2023 | 17.0°C | 14.5°C | 11.9°C | 20.2°C | 8.6°C | 267 mm | 85% | 1.2 m/s | 5.9 |
| 2022 | 18.1°C | 15.1°C | 12.2°C | 21.8°C | 9.0°C | 88 mm | 81% | 1 m/s | 6.6 |
| 2021 | 16.9°C | 14.6°C | 12.3°C | 19.3°C | 9.9°C | 241 mm | 86% | 1.3 m/s | 5.1 |
| 2020 | 16.1°C | 13.4°C | 10.6°C | 19.3°C | 6.5°C | 230 mm | 83% | 1.3 m/s | 6.3 |
| 2019 | 15.6°C | 13.0°C | 10.3°C | 19.7°C | 7.2°C | 245 mm | 84% | 1.4 m/s | 5.3 |
| 2018 | 18.4°C | 15.4°C | 12.4°C | 21.5°C | 8.2°C | 104 mm | 83% | 1 m/s | 6.3 |
| 2017 🔥 | 18.9°C | 15.8°C | 12.7°C | 21.9°C | 8.7°C | 87 mm | 81% | 1 m/s | 7.1 |
| 2016 | 15.5°C | 12.7°C | 9.9°C | 18.4°C | 8.3°C | 233 mm | 84% | 1.3 m/s | 5.8 |
| 2015 | 15.9°C | 12.9°C | 10.0°C | 20.3°C | 6.4°C | 167 mm | 84% | 1.1 m/s | 6.1 |
| 2014 | 17.0°C | 14.1°C | 11.3°C | 21.0°C | 5.4°C | 218 mm | 85% | 1 m/s | 5.9 |
| 2013 | 16.7°C | 13.8°C | 11.0°C | 20.5°C | 7.6°C | 177 mm | 83% | 1.2 m/s | 5.7 |
| 2012 | 16.8°C | 13.9°C | 11.0°C | 22.1°C | 7.8°C | 147 mm | 85% | 1.1 m/s | 6 |
| 2011 | 17.5°C | 14.5°C | 11.6°C | 19.8°C | 7.6°C | 192 mm | 83% | 1 m/s | 6.1 |
| 2010 | 17.3°C | 14.7°C | 12.1°C | 20.2°C | 9.6°C | 268 mm | 84% | 1.3 m/s | 5.6 |
| 2009 | 15.2°C | 12.6°C | 10.0°C | 17.7°C | 6.3°C | 229 mm | 84% | 1.3 m/s | 5.4 |
| 2008 | 15.9°C | 13.1°C | 10.4°C | 20.0°C | 6.9°C | 188 mm | 84% | 1.2 m/s | 5.7 |
| 2007 | 16.9°C | 14.0°C | 11.2°C | 21.0°C | 7.2°C | 181 mm | 84% | 1.1 m/s | 5.6 |
| 2006 | 14.2°C | 11.2°C | 8.1°C | 16.6°C | 5.1°C | 163 mm | 81% | 1.1 m/s | 6.1 |
| 2005 | 17.8°C | 15.0°C | 12.2°C | 22.1°C | 9.2°C | 182 mm | 85% | 1.2 m/s | 5.6 |
| 2004 ❄️ | 13.4°C | 10.8°C | 8.2°C | 17.0°C | 5.5°C | 218 mm | 83% | 1.5 m/s | 5.4 |
| 2003 | 16.0°C | 13.2°C | 10.4°C | 19.6°C | 8.2°C | 172 mm | 84% | 1.3 m/s | 6 |
| 2002 | 15.6°C | 13.0°C | 10.5°C | 19.6°C | 6.5°C | 145 mm | 84% | 1.4 m/s | 5.5 |
| 2001 | 16.7°C | 14.3°C | 11.9°C | 19.6°C | 7.1°C | 264 mm | 86% | 1.3 m/s | 4.7 |
| 2000 | 16.4°C | 13.6°C | 10.8°C | 18.6°C | 7.9°C | 129 mm | 83% | 1.3 m/s | 6.1 |
| 1999 | 15.9°C | 13.1°C | 10.4°C | 18.8°C | 6.6°C | 69 mm | 81% | 1.2 m/s | 6.3 |
| 1998 | 16.3°C | 13.7°C | 11.2°C | 19.9°C | 7.2°C | 212 mm | 84% | 1.2 m/s | 5.7 |
| 1997 | 14.3°C | 11.7°C | 9.0°C | 17.4°C | 5.1°C | 197 mm | 83% | 1.3 m/s | 5.7 |
| 1996 | 15.7°C | 12.7°C | 9.6°C | 21.1°C | 5.8°C | 124 mm | 81% | 1.1 m/s | 6.4 |
| 1995 🌧️ | 16.2°C | 13.9°C | 11.6°C | 19.0°C | 6.7°C | 317 mm | 86% | 1.3 m/s | 5.5 |
| 1994 | 15.7°C | 12.9°C | 10.0°C | 18.6°C | 6.7°C | 99 mm | 82% | 1.1 m/s | 6.5 |
| 1993 | 15.2°C | 12.4°C | 9.5°C | 19.7°C | 4.8°C | 166 mm | 83% | 1.1 m/s | 5.4 |
| 1992 | 16.4°C | 13.4°C | 10.4°C | 18.8°C | 5.9°C | 183 mm | 80% | 1.3 m/s | 5.7 |
| 1991 | 15.7°C | 12.9°C | 10.1°C | 19.1°C | 5.9°C | 231 mm | 84% | 1.1 m/s | 5.8 |
| 1990 | 15.7°C | 13.1°C | 10.5°C | 18.6°C | 7.2°C | 272 mm | 83% | 1.6 m/s | 5.5 |
| 1989 | 15.9°C | 13.2°C | 10.4°C | 18.3°C | 7.4°C | 287 mm | 82% | 1.5 m/s | 5.6 |
| 1988 | 17.6°C | 14.6°C | 11.7°C | 20.7°C | 7.8°C | 75 mm | 82% | 1.2 m/s | 6.1 |
| 1987 | 15.9°C | 13.1°C | 10.4°C | 20.7°C | 8.5°C | 230 mm | 83% | 1.2 m/s | 5.2 |
| 1986 | 17.4°C | 14.3°C | 11.3°C | 20.2°C | 6.6°C | 170 mm | 81% | 1.2 m/s | 6.1 |
| 1985 | 17.2°C | 14.5°C | 11.7°C | 20.2°C | 7.3°C | 285 mm | 84% | 1.2 m/s | 5.3 |
| 1984 | 17.2°C | 14.4°C | 11.6°C | 22.0°C | 8.5°C | 228 mm | 83% | 1.3 m/s | 5.2 |
| 1983 | 15.2°C | 12.5°C | 9.8°C | 18.3°C | 7.3°C | 242 mm | 84% | 1.4 m/s | — |
| 1982 | 14.4°C | 11.7°C | 9.0°C | 17.8°C | 5.4°C | 168 mm | 84% | 1.3 m/s | — |
| 1981 | 17.4°C | 14.9°C | 12.4°C | 20.7°C | 9.3°C | 215 mm | 86% | 1.2 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 16.3°C with lows near 10.8°C (mean 13.6°C), based on 45 years of NASA POWER data.
December averages 194 mm of rainfall in Greymouth, a relatively wet time of year. The wettest on record was 317 mm in 1995.
The hottest December reached 22.1°C in 2005. The coldest dipped to 4.8°C in 1993.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 0.9°C. Daytime highs moved from 16.3°C to 17.2°C and overnight lows from 10.9°C to 11.8°C over the same span.
December is one of the warmer months of the year in Greymouth and a relatively wet time of year, so plan for around 16.3°C daytime highs and 10.8°C at night.
Not quite — December is the 9th coolest month in Greymouth, averaging 13.6°C.
For December in Greymouth, pack light layers you can adjust through the day, with typical highs of 16.3°C and lows of 10.8°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 83% — quite humid.
Average wind speed in December is 1.2 m/s. The windiest December on record averaged 1.6 m/s (1990).
The wettest December on record was 1995 with 317 mm. On average, December sees 194 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 Greymouth 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.
