December is one of the warmer months of the year in New Plymouth, with average highs near 18.7°C and lows around 12.6°C (mean 15.7°C). It is about average for rainfall, averaging 107 mm of rainfall and 83% relative humidity across the period.
December is one of the warmer months of the year in New Plymouth. Across 45 years of records, the warmest December in New Plymouth was 2021 — when the month averaged 17.8°C — while the coldest was 2006 at 13°C. Typical December days reach 18.7°C with nights near 12.6°C. The long-term trend is warming, about 0.2°C per decade.
December is about average for rainfall in New Plymouth, averaging 107 mm of rainfall. The wettest December on record was 2011 with 246 mm, while the driest was 2017 at 31 mm.
Relative humidity in New Plymouth during December averages 83%. The most humid December was 2023 at 87%, and the least humid was 1983 at 80%.
December receives about 6.4 kWh/m²/day of solar energy in New Plymouth. The sunniest December was 2017 at 7.4 kWh/m²/day, and the cloudiest was 2001 at 5.2.
Average wind speed in New Plymouth during December is 4 m/s. The windiest December was 2004 at 5.2 m/s, while the calmest was 2022 at 3.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 15.8°C | 15.0°C | 15.4°C | 16.0°C | 16.5°C | +0.7°C |
| Avg High | 19.0°C | 18.1°C | 18.3°C | 19.1°C | 19.5°C | +0.5°C |
| Avg Low | 12.7°C | 11.9°C | 12.5°C | 12.9°C | 13.5°C | +0.8°C |
| Avg Rain | 104 mm | 90 mm | 111 mm | 101 mm | 140 mm | +36 mm |
December temperatures in New Plymouth have risen by about 0.8°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 5°C (1992) to a record high of 26.9°C (2012).
Rainfall in December is about average for rainfall, averaging 107 mm, with a wettest year of 246 mm.
One of the best times to visit New Plymouth
December is one of the best times to visit New Plymouth. Expect days averaging 18.7°C and nights around 12.6°C (mean 15.7°C) — warmer than New Plymouth's yearly average — with higher rainfall (107 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 | 19.5°C | 16.5°C | 13.4°C | 24.0°C | 9.9°C | 149 mm | 82% | 4.2 m/s | — |
| 2024 | 19.5°C | 16.4°C | 13.2°C | 21.5°C | 8.3°C | 67 mm | 86% | 4.2 m/s | 6.5 |
| 2023 | 19.3°C | 16.6°C | 13.9°C | 22.9°C | 11.3°C | 156 mm | 87% | 3.8 m/s | 5.9 |
| 2022 | 20.1°C | 16.9°C | 13.6°C | 23.6°C | 9.1°C | 127 mm | 84% | 3.4 m/s | 6.7 |
| 2021 🔥 | 20.3°C | 17.8°C | 15.3°C | 23.8°C | 12.7°C | 223 mm | 87% | 3.9 m/s | 6 |
| 2020 | 18.0°C | 14.9°C | 11.7°C | 20.4°C | 6.1°C | 118 mm | 84% | 4.4 m/s | 6.7 |
| 2019 | 19.0°C | 15.8°C | 12.6°C | 23.6°C | 8.9°C | 130 mm | 84% | 4.6 m/s | 6.8 |
| 2018 | 19.9°C | 16.8°C | 13.7°C | 23.3°C | 8.9°C | 96 mm | 84% | 3.5 m/s | 6.5 |
| 2017 | 20.6°C | 17.4°C | 14.1°C | 24.9°C | 10.1°C | 31 mm | 83% | 3.5 m/s | 7.4 |
| 2016 | 17.7°C | 14.6°C | 11.5°C | 20.9°C | 8.1°C | 61 mm | 84% | 3.9 m/s | 6.8 |
| 2015 | 18.2°C | 15.1°C | 12.0°C | 23.6°C | 8.3°C | 42 mm | 83% | 3.9 m/s | 7.1 |
| 2014 | 19.0°C | 15.7°C | 12.5°C | 23.5°C | 5.8°C | 80 mm | 83% | 3.5 m/s | 6.4 |
| 2013 | 18.8°C | 15.9°C | 12.9°C | 21.3°C | 8.7°C | 109 mm | 82% | 4 m/s | 6.5 |
| 2012 | 19.4°C | 16.3°C | 13.2°C | 26.9°C | 7.8°C | 85 mm | 85% | 3.7 m/s | 6.1 |
| 2011 🌧️ | 19.3°C | 16.1°C | 12.8°C | 21.7°C | 7.8°C | 246 mm | 83% | 3.8 m/s | 6.3 |
| 2010 | 19.4°C | 16.3°C | 13.2°C | 22.9°C | 8.5°C | 128 mm | 85% | 3.8 m/s | 6 |
| 2009 | 18.0°C | 14.8°C | 11.7°C | 20.5°C | 8.6°C | 121 mm | 84% | 4 m/s | 6.5 |
| 2008 | 18.7°C | 15.7°C | 12.6°C | 22.3°C | 8.9°C | 94 mm | 83% | 3.9 m/s | 6.4 |
| 2007 | 19.3°C | 16.2°C | 13.1°C | 22.2°C | 9.0°C | 77 mm | 82% | 3.6 m/s | 6.2 |
| 2006 ❄️ | 16.0°C | 13.0°C | 10.1°C | 19.4°C | 5.8°C | 87 mm | 82% | 4.1 m/s | 6.6 |
| 2005 | 19.4°C | 16.7°C | 14.1°C | 23.3°C | 10.1°C | 111 mm | 85% | 4 m/s | 6 |
| 2004 | 15.8°C | 13.3°C | 10.7°C | 19.7°C | 7.1°C | 115 mm | 82% | 5.2 m/s | 6.3 |
| 2003 | 18.8°C | 15.8°C | 12.9°C | 22.3°C | 8.0°C | 130 mm | 85% | 4 m/s | 6 |
| 2002 | 18.4°C | 15.4°C | 12.4°C | 21.4°C | 9.3°C | 118 mm | 82% | 4.4 m/s | 6.2 |
| 2001 | 19.3°C | 16.7°C | 14.1°C | 22.1°C | 10.9°C | 191 mm | 84% | 4.8 m/s | 5.2 |
| 2000 | 19.4°C | 16.4°C | 13.4°C | 22.2°C | 11.1°C | 65 mm | 83% | 3.9 m/s | 6.4 |
| 1999 | 17.9°C | 14.5°C | 11.2°C | 21.2°C | 7.0°C | 33 mm | 81% | 4.2 m/s | 6.9 |
| 1998 | 19.1°C | 16.0°C | 13.0°C | 22.4°C | 10.7°C | 67 mm | 82% | 4 m/s | 6.6 |
| 1997 | 18.0°C | 14.7°C | 11.5°C | 21.5°C | 9.1°C | 73 mm | 81% | 3.9 m/s | 6.6 |
| 1996 | 17.6°C | 14.6°C | 11.6°C | 21.9°C | 6.9°C | 119 mm | 83% | 4.1 m/s | 6.3 |
| 1995 | 19.5°C | 16.4°C | 13.3°C | 23.5°C | 9.4°C | 108 mm | 84% | 4.2 m/s | 6.5 |
| 1994 | 18.5°C | 15.1°C | 11.7°C | 21.5°C | 8.0°C | 65 mm | 83% | 3.7 m/s | 6.9 |
| 1993 | 17.1°C | 14.1°C | 11.1°C | 21.3°C | 8.0°C | 130 mm | 84% | 4 m/s | 6.2 |
| 1992 | 17.8°C | 14.7°C | 11.6°C | 20.9°C | 5.0°C | 168 mm | 84% | 4.4 m/s | 5.8 |
| 1991 | 17.1°C | 14.2°C | 11.3°C | 20.2°C | 6.2°C | 97 mm | 85% | 3.9 m/s | 6.3 |
| 1990 | 18.4°C | 15.4°C | 12.4°C | 22.1°C | 9.2°C | 39 mm | 82% | 4.6 m/s | 6.7 |
| 1989 | 17.9°C | 14.8°C | 11.6°C | 20.9°C | 6.9°C | 114 mm | 81% | 4.9 m/s | 6.5 |
| 1988 | 20.3°C | 16.9°C | 13.5°C | 23.6°C | 10.0°C | 68 mm | 81% | 3.6 m/s | 6.9 |
| 1987 | 18.3°C | 15.4°C | 12.5°C | 21.6°C | 9.9°C | 148 mm | 83% | 4.2 m/s | 6.2 |
| 1986 | 19.0°C | 15.6°C | 12.2°C | 21.2°C | 7.2°C | 66 mm | 80% | 3.9 m/s | 6.7 |
| 1985 | 19.7°C | 16.6°C | 13.6°C | 21.8°C | 8.8°C | 117 mm | 82% | 3.6 m/s | 6.6 |
| 1984 | 20.6°C | 17.2°C | 13.8°C | 24.5°C | 10.5°C | 127 mm | 82% | 3.7 m/s | 6.2 |
| 1983 | 18.0°C | 14.8°C | 11.6°C | 22.8°C | 7.8°C | 92 mm | 80% | 4.5 m/s | — |
| 1982 | 17.5°C | 14.4°C | 11.4°C | 19.7°C | 5.9°C | 111 mm | 81% | 4.6 m/s | — |
| 1981 | 19.8°C | 16.9°C | 14.1°C | 24.0°C | 11.0°C | 92 mm | 85% | 3.8 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 18.7°C with lows near 12.6°C (mean 15.7°C), based on 45 years of NASA POWER data.
December averages 107 mm of rainfall in New Plymouth, about average for rainfall. The wettest on record was 246 mm in 2011.
The hottest December reached 26.9°C in 2012. The coldest dipped to 5°C in 1992.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 0.8°C. Daytime highs moved from 19.1°C to 19.7°C and overnight lows from 12.9°C to 13.9°C over the same span.
December is one of the warmer months of the year in New Plymouth and about average for rainfall, so plan for around 18.7°C daytime highs and 12.6°C at night.
Not quite — December is the 9th coolest month in New Plymouth, averaging 15.7°C.
For December in New Plymouth, pack light layers you can adjust through the day, with typical highs of 18.7°C and lows of 12.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 83% — quite humid.
Average wind speed in December is 4 m/s. The windiest December on record averaged 5.2 m/s (2004).
The wettest December on record was 2011 with 246 mm. On average, December sees 107 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 New Plymouth 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.
