December is one of the warmer months of the year in Timaru, with average highs near 17.4°C and lows around 11.4°C (mean 14.4°C). It is a relatively wet time of year, averaging 69 mm of rainfall and 74% relative humidity across the period.
December is one of the warmer months of the year in Timaru. Across 45 years of records, the warmest December in Timaru was 2017 — when the month averaged 16.8°C — while the coldest was 2004 at 11.9°C. Typical December days reach 17.4°C with nights near 11.4°C. The long-term trend is warming, about 0.2°C per decade.
December is a relatively wet time of year in Timaru, averaging 69 mm of rainfall. The wettest December on record was 2004 with 128 mm, while the driest was 2003 at 21 mm.
Relative humidity in Timaru during December averages 74%. The most humid December was 2018 at 80%, and the least humid was 1997 at 68%.
December receives about 6.2 kWh/m²/day of solar energy in Timaru. The sunniest December was 2003 at 6.9 kWh/m²/day, and the cloudiest were 1993, 2018 and 2021 at 5.5.
Average wind speed in Timaru during December is 3.8 m/s. The windiest December was 2004 at 4.8 m/s, while the calmest were 1985 and 2005 at 3.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 14.4°C | 13.8°C | 14.2°C | 14.9°C | 15.0°C | +0.6°C |
| Avg High | 17.2°C | 16.9°C | 17.2°C | 18.0°C | 18.0°C | +0.8°C |
| Avg Low | 11.6°C | 10.7°C | 11.1°C | 11.8°C | 12.1°C | +0.5°C |
| Avg Rain | 92 mm | 69 mm | 66 mm | 54 mm | 66 mm | -26 mm |
December temperatures in Timaru have risen by about 0.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 6.1°C (1995) to a record high of 26.8°C (2010).
Rainfall in December is a relatively wet time of year, averaging 69 mm, with a wettest year of 128 mm.
One of the best times to visit Timaru
December is one of the best times to visit Timaru. Expect days averaging 17.4°C and nights around 11.4°C (mean 14.4°C) — warmer than Timaru's yearly average — with moderate rainfall (69 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 | 17.4°C | 14.5°C | 11.6°C | 22.8°C | 8.4°C | 53 mm | 72% | 3.9 m/s | — |
| 2024 | 18.6°C | 15.7°C | 12.8°C | 24.1°C | 8.6°C | 59 mm | 76% | 4 m/s | 6.1 |
| 2023 | 18.8°C | 15.4°C | 12.1°C | 25.8°C | 8.3°C | 47 mm | 74% | 3.9 m/s | 5.8 |
| 2022 | 17.4°C | 14.9°C | 12.4°C | 24.7°C | 8.5°C | 55 mm | 79% | 3.5 m/s | 6 |
| 2021 | 17.6°C | 14.8°C | 12.1°C | 22.7°C | 10.0°C | 110 mm | 78% | 3.9 m/s | 5.5 |
| 2020 | 18.0°C | 14.8°C | 11.6°C | 25.0°C | 7.7°C | 72 mm | 71% | 4 m/s | 6.5 |
| 2019 | 17.8°C | 14.7°C | 11.5°C | 21.8°C | 8.5°C | 57 mm | 70% | 4.5 m/s | 6.6 |
| 2018 | 17.7°C | 14.9°C | 12.2°C | 25.5°C | 9.5°C | 66 mm | 80% | 3.5 m/s | 5.5 |
| 2017 🔥 | 19.9°C | 16.8°C | 13.6°C | 26.0°C | 9.9°C | 49 mm | 73% | 3.7 m/s | 6.5 |
| 2016 | 17.4°C | 14.2°C | 11.1°C | 22.8°C | 8.3°C | 72 mm | 73% | 3.9 m/s | 6.1 |
| 2015 | 18.0°C | 14.4°C | 10.8°C | 25.2°C | 6.4°C | 42 mm | 71% | 3.7 m/s | 6.5 |
| 2014 | 17.6°C | 14.5°C | 11.4°C | 23.1°C | 7.0°C | 30 mm | 75% | 3.9 m/s | 6.2 |
| 2013 | 17.9°C | 14.9°C | 11.9°C | 23.7°C | 9.0°C | 66 mm | 76% | 3.5 m/s | 5.9 |
| 2012 | 18.4°C | 15.0°C | 11.5°C | 24.8°C | 8.2°C | 30 mm | 75% | 3.7 m/s | 6.1 |
| 2011 | 17.0°C | 14.3°C | 11.7°C | 24.6°C | 8.2°C | 52 mm | 78% | 3.4 m/s | 6.3 |
| 2010 | 18.7°C | 15.5°C | 12.3°C | 26.8°C | 7.4°C | 73 mm | 72% | 4 m/s | 5.7 |
| 2009 | 16.7°C | 13.6°C | 10.4°C | 22.4°C | 6.8°C | 57 mm | 73% | 3.9 m/s | 6.2 |
| 2008 | 17.1°C | 14.2°C | 11.3°C | 23.1°C | 8.0°C | 81 mm | 75% | 3.8 m/s | 6.1 |
| 2007 | 17.9°C | 14.7°C | 11.4°C | 24.8°C | 8.8°C | 59 mm | 74% | 3.7 m/s | 6.1 |
| 2006 | 15.1°C | 12.3°C | 9.4°C | 19.9°C | 6.7°C | 101 mm | 75% | 4 m/s | 6.2 |
| 2005 | 18.1°C | 15.4°C | 12.8°C | 22.9°C | 10.0°C | 84 mm | 79% | 3.3 m/s | 5.6 |
| 2004 ❄️ 🌧️ | 14.7°C | 11.9°C | 9.1°C | 19.3°C | 6.2°C | 128 mm | 74% | 4.8 m/s | 6.2 |
| 2003 | 18.3°C | 14.8°C | 11.4°C | 24.1°C | 9.3°C | 21 mm | 70% | 3.8 m/s | 6.9 |
| 2002 | 17.6°C | 14.4°C | 11.3°C | 23.3°C | 8.1°C | 44 mm | 71% | 4.2 m/s | 6.3 |
| 2001 | 17.7°C | 15.0°C | 12.2°C | 24.1°C | 7.3°C | 39 mm | 75% | 3.5 m/s | 5.8 |
| 2000 | 18.5°C | 15.3°C | 12.0°C | 23.4°C | 9.4°C | 47 mm | 72% | 4 m/s | 6.5 |
| 1999 | 16.7°C | 13.6°C | 10.6°C | 22.5°C | 8.2°C | 47 mm | 73% | 3.8 m/s | 6.1 |
| 1998 | 18.1°C | 14.9°C | 11.7°C | 24.8°C | 8.8°C | 44 mm | 73% | 3.8 m/s | 5.9 |
| 1997 | 16.7°C | 13.4°C | 10.0°C | 22.4°C | 6.5°C | 57 mm | 68% | 4.1 m/s | 6.2 |
| 1996 | 17.0°C | 13.8°C | 10.6°C | 21.4°C | 7.8°C | 48 mm | 72% | 3.9 m/s | 6.6 |
| 1995 | 18.0°C | 14.5°C | 11.0°C | 22.7°C | 6.1°C | 77 mm | 75% | 3.9 m/s | 6 |
| 1994 | 17.7°C | 14.3°C | 10.8°C | 24.5°C | 8.3°C | 37 mm | 70% | 3.7 m/s | 6.6 |
| 1993 | 15.6°C | 12.9°C | 10.2°C | 21.3°C | 7.4°C | 117 mm | 79% | 3.4 m/s | 5.5 |
| 1992 | 15.4°C | 12.7°C | 10.1°C | 20.7°C | 7.1°C | 92 mm | 79% | 4.4 m/s | 5.8 |
| 1991 | 16.2°C | 13.4°C | 10.7°C | 22.8°C | 6.7°C | 91 mm | 77% | 3.6 m/s | 6.1 |
| 1990 | 18.1°C | 14.8°C | 11.4°C | 22.5°C | 7.6°C | 78 mm | 70% | 4.5 m/s | 6.6 |
| 1989 | 17.4°C | 14.4°C | 11.3°C | 21.9°C | 7.9°C | 101 mm | 71% | 3.8 m/s | 6.5 |
| 1988 | 19.4°C | 16.0°C | 12.7°C | 23.7°C | 8.9°C | 56 mm | 71% | 3.7 m/s | 6.8 |
| 1987 | 16.4°C | 13.8°C | 11.2°C | 22.3°C | 8.6°C | 81 mm | 76% | 3.6 m/s | 5.9 |
| 1986 | 17.1°C | 14.4°C | 11.7°C | 21.7°C | 7.5°C | 88 mm | 76% | 3.6 m/s | 6.8 |
| 1985 | 16.8°C | 14.4°C | 11.9°C | 22.3°C | 7.6°C | 87 mm | 79% | 3.3 m/s | 5.9 |
| 1984 | 17.3°C | 14.8°C | 12.3°C | 21.2°C | 9.4°C | 106 mm | 77% | 3.7 m/s | 5.9 |
| 1983 | 16.1°C | 13.2°C | 10.4°C | 22.4°C | 7.8°C | 124 mm | 76% | 4 m/s | — |
| 1982 | 16.6°C | 13.3°C | 10.1°C | 22.6°C | 6.6°C | 95 mm | 70% | 3.5 m/s | — |
| 1981 | 18.1°C | 15.5°C | 12.8°C | 23.1°C | 10.1°C | 91 mm | 78% | 3.6 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 17.4°C with lows near 11.4°C (mean 14.4°C), based on 45 years of NASA POWER data.
December averages 69 mm of rainfall in Timaru, a relatively wet time of year. The wettest on record was 128 mm in 2004.
The hottest December reached 26.8°C in 2010. The coldest dipped to 6.1°C in 1995.
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 17°C to 18°C and overnight lows from 11.5°C to 12.2°C over the same span.
December is one of the warmer months of the year in Timaru and a relatively wet time of year, so plan for around 17.4°C daytime highs and 11.4°C at night.
Not quite — December is the 9th coolest month in Timaru, averaging 14.4°C.
For December in Timaru, pack light layers you can adjust through the day, with typical highs of 17.4°C and lows of 11.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 74% — moderately humid.
Average wind speed in December is 3.8 m/s. The windiest December on record averaged 4.8 m/s (2004).
The wettest December on record was 2004 with 128 mm. On average, December sees 69 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 Timaru 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.
