December is one of the warmer months of the year in Goonellabah, with average highs near 29.3°C and lows around 19.6°C (mean 24.5°C). It is a relatively wet time of year, averaging 132 mm of rainfall and 68% relative humidity across the period.
December is one of the warmer months of the year in Goonellabah. Across 45 years of records, the warmest December in Goonellabah was 1990 — when the month averaged 27.4°C — while the coldest was 1983 at 21.4°C. Typical December days reach 29.3°C with nights near 19.6°C. The long-term trend is warming, about 0.2°C per decade.
December is a relatively wet time of year in Goonellabah, averaging 132 mm of rainfall. The wettest December on record was 2020 with 357 mm, while the driest was 2013 at 36 mm.
Relative humidity in Goonellabah during December averages 68%. The most humid December was 2010 at 80%, and the least humid was 2019 at 58%.
December receives about 6.6 kWh/m²/day of solar energy in Goonellabah. The sunniest December was 2005 at 7.7 kWh/m²/day, and the cloudiest was 2010 at 4.9.
Average wind speed in Goonellabah during December is 2.9 m/s. The windiest December was 1988 at 3.4 m/s, while the calmest were 2021 and 2023 at 2.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 24.0°C | 24.0°C | 24.9°C | 24.5°C | 24.7°C | +0.7°C |
| Avg High | 28.9°C | 28.8°C | 29.9°C | 29.3°C | 29.3°C | +0.4°C |
| Avg Low | 19.1°C | 19.2°C | 19.9°C | 19.8°C | 20.2°C | +1.1°C |
| Avg Rain | 148 mm | 142 mm | 107 mm | 117 mm | 155 mm | +7 mm |
December temperatures in Goonellabah have risen by about 0.5°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 13.3°C (2010) to a record high of 42°C (1990).
Rainfall in December is a relatively wet time of year, averaging 132 mm, with a wettest year of 357 mm.
A good time to visit Goonellabah
December is a good time to visit Goonellabah, with days averaging 29.3°C and nights around 19.6°C (mean 24.5°C, warmer than Goonellabah's yearly average) and higher rainfall. October and November are marginally more temperate, but December still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 30.4°C | 25.0°C | 19.7°C | 37.9°C | 16.2°C | 100 mm | 64% | 2.9 m/s | — |
| 2024 | 29.9°C | 25.5°C | 21.0°C | 36.3°C | 17.7°C | 103 mm | 74% | 2.6 m/s | 6.8 |
| 2023 | 31.8°C | 26.6°C | 21.5°C | 36.8°C | 17.2°C | 117 mm | 68% | 2.5 m/s | 7.2 |
| 2022 | 27.7°C | 23.0°C | 18.3°C | 36.1°C | 15.9°C | 74 mm | 65% | 3.1 m/s | 6.4 |
| 2021 | 27.0°C | 23.2°C | 19.5°C | 33.3°C | 15.6°C | 181 mm | 78% | 2.5 m/s | 6.4 |
| 2020 🌧️ | 29.0°C | 25.1°C | 21.1°C | 37.7°C | 18.3°C | 357 mm | 74% | 3.2 m/s | 5.8 |
| 2019 | 31.6°C | 26.0°C | 20.5°C | 37.8°C | 16.6°C | 64 mm | 58% | 2.8 m/s | 7.3 |
| 2018 | 30.3°C | 25.3°C | 20.2°C | 40.1°C | 18.0°C | 61 mm | 65% | 3.2 m/s | 6.9 |
| 2017 | 30.3°C | 25.3°C | 20.2°C | 37.7°C | 15.0°C | 102 mm | 69% | 2.8 m/s | 7 |
| 2016 | 32.4°C | 26.6°C | 20.8°C | 40.2°C | 18.3°C | 49 mm | 60% | 3.2 m/s | 6.8 |
| 2015 | 28.1°C | 23.7°C | 19.3°C | 36.3°C | 16.3°C | 113 mm | 69% | 3 m/s | 6.3 |
| 2014 | 29.5°C | 24.9°C | 20.3°C | 37.4°C | 16.6°C | 203 mm | 70% | 3 m/s | 6.1 |
| 2013 | 29.6°C | 24.0°C | 18.5°C | 40.1°C | 13.3°C | 36 mm | 65% | 2.7 m/s | 7.1 |
| 2012 | 30.0°C | 25.2°C | 20.4°C | 37.8°C | 16.7°C | 105 mm | 66% | 2.8 m/s | 6.6 |
| 2011 | 25.3°C | 21.6°C | 17.9°C | 29.3°C | 14.3°C | 149 mm | 73% | 3 m/s | 5.5 |
| 2010 | 26.2°C | 22.8°C | 19.5°C | 31.4°C | 13.3°C | 287 mm | 80% | 2.7 m/s | 4.9 |
| 2009 | 30.8°C | 26.0°C | 21.1°C | 39.7°C | 16.4°C | 145 mm | 66% | 3 m/s | 6.5 |
| 2008 | 29.6°C | 24.5°C | 19.4°C | 35.9°C | 16.1°C | 105 mm | 69% | 2.9 m/s | 6.7 |
| 2007 | 27.3°C | 23.6°C | 19.9°C | 32.1°C | 18.1°C | 127 mm | 73% | 2.9 m/s | 5.6 |
| 2006 | 27.9°C | 23.1°C | 18.2°C | 35.7°C | 16.5°C | 75 mm | 64% | 2.9 m/s | 6.3 |
| 2005 | 32.5°C | 26.6°C | 20.8°C | 39.6°C | 15.4°C | 117 mm | 65% | 2.8 m/s | 7.7 |
| 2004 | 28.3°C | 23.8°C | 19.3°C | 37.9°C | 14.5°C | 153 mm | 71% | 3.2 m/s | 6 |
| 2003 | 30.2°C | 25.1°C | 20.0°C | 39.2°C | 16.2°C | 94 mm | 66% | 3.2 m/s | 6.2 |
| 2002 | 30.5°C | 25.2°C | 19.8°C | 39.5°C | 15.4°C | 102 mm | 58% | 3 m/s | 7.2 |
| 2001 | 32.0°C | 26.3°C | 20.5°C | 39.6°C | 17.8°C | 54 mm | 62% | 3.2 m/s | 6.6 |
| 2000 | 29.9°C | 25.0°C | 20.1°C | 38.6°C | 17.2°C | 92 mm | 65% | 2.9 m/s | 6.6 |
| 1999 | 26.1°C | 21.8°C | 17.5°C | 33.4°C | 15.3°C | 132 mm | 71% | 2.6 m/s | 6.7 |
| 1998 | 28.9°C | 24.3°C | 19.6°C | 36.4°C | 15.7°C | 111 mm | 71% | 2.6 m/s | 6.6 |
| 1997 | 31.8°C | 26.8°C | 21.8°C | 38.6°C | 18.6°C | 84 mm | 65% | 3 m/s | 6.8 |
| 1996 | 27.9°C | 23.4°C | 18.9°C | 37.5°C | 15.1°C | 146 mm | 71% | 2.6 m/s | 6.5 |
| 1995 | 28.4°C | 23.2°C | 18.1°C | 33.4°C | 13.9°C | 148 mm | 67% | 3 m/s | 7.1 |
| 1994 | 28.3°C | 23.6°C | 18.8°C | 37.4°C | 14.3°C | 170 mm | 68% | 3.2 m/s | 7 |
| 1993 | 28.7°C | 23.5°C | 18.3°C | 35.6°C | 13.8°C | 141 mm | 65% | 2.9 m/s | 6.9 |
| 1992 | 27.8°C | 23.2°C | 18.7°C | 34.4°C | 13.7°C | 124 mm | 69% | 3.1 m/s | 6.7 |
| 1991 | 27.0°C | 22.7°C | 18.4°C | 33.9°C | 15.0°C | 293 mm | 73% | 2.8 m/s | 6.8 |
| 1990 🔥 | 33.2°C | 27.4°C | 21.6°C | 42.0°C | 18.3°C | 70 mm | 59% | 3.3 m/s | 6.9 |
| 1989 | 27.6°C | 23.0°C | 18.4°C | 32.0°C | 15.7°C | 145 mm | 71% | 3 m/s | 6.6 |
| 1988 | 27.5°C | 23.8°C | 20.0°C | 34.6°C | 17.4°C | 244 mm | 76% | 3.4 m/s | 6 |
| 1987 | 29.4°C | 24.6°C | 19.7°C | 35.0°C | 14.0°C | 158 mm | 67% | 3 m/s | 6.7 |
| 1986 | 29.0°C | 23.8°C | 18.6°C | 38.2°C | 14.6°C | 61 mm | 65% | 2.8 m/s | 6.9 |
| 1985 | 30.7°C | 25.1°C | 19.4°C | 37.4°C | 15.1°C | 109 mm | 65% | 2.9 m/s | 6.9 |
| 1984 | 29.6°C | 24.2°C | 18.7°C | 36.4°C | 14.0°C | 129 mm | 66% | 2.7 m/s | 6.5 |
| 1983 ❄️ | 25.6°C | 21.4°C | 17.3°C | 33.9°C | 14.2°C | 220 mm | 76% | 2.7 m/s | — |
| 1982 | 30.2°C | 24.9°C | 19.5°C | 35.2°C | 16.4°C | 145 mm | 65% | 2.8 m/s | — |
| 1981 | 30.8°C | 25.6°C | 20.4°C | 41.2°C | 17.8°C | 120 mm | 69% | 2.8 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 29.3°C with lows near 19.6°C (mean 24.5°C), based on 45 years of NASA POWER data.
December averages 132 mm of rainfall in Goonellabah, a relatively wet time of year. The wettest on record was 357 mm in 2020.
The hottest December reached 42°C in 1990. The coldest dipped to 13.3°C in 2010.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 0.5°C. Daytime highs moved from 29.4°C to 29.4°C and overnight lows from 19.1°C to 20°C over the same span.
December is one of the warmer months of the year in Goonellabah and a relatively wet time of year, so plan for around 29.3°C daytime highs and 19.6°C at night.
Not quite — December is the 10th coolest month in Goonellabah, averaging 24.5°C.
For December in Goonellabah, pack light layers you can adjust through the day, with typical highs of 29.3°C and lows of 19.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 68% — moderately humid.
Average wind speed in December is 2.9 m/s. The windiest December on record averaged 3.4 m/s (1988).
The wettest December on record was 2020 with 357 mm. On average, December sees 132 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 Goonellabah 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.
