December is one of the warmer months of the year in Muswellbrook, with average highs near 29.6°C and lows around 15.2°C (mean 22.4°C). It is a relatively wet time of year, averaging 82 mm of rainfall and 58% relative humidity across the period.
December is one of the warmer months of the year in Muswellbrook. Across 45 years of records, the warmest December in Muswellbrook was 1990 — when the month averaged 25.7°C — while the coldest was 2011 at 18°C. Typical December days reach 29.6°C with nights near 15.2°C. The long-term trend is warming, about 0.3°C per decade.
December is a relatively wet time of year in Muswellbrook, averaging 82 mm of rainfall. The wettest December on record was 1992 with 176 mm, while the driest was 2019 at 2 mm.
Relative humidity in Muswellbrook during December averages 58%. The most humid December was 2007 at 77%, and the least humid was 2019 at 41%.
December receives about 7 kWh/m²/day of solar energy in Muswellbrook. The sunniest December was 2005 at 8.4 kWh/m²/day, and the cloudiest was 2011 at 5.9.
Average wind speed in Muswellbrook during December is 0.9 m/s. The windiest Decembers were 2015, 2019 and 2020, among others at 1 m/s, while the calmest were 2013, 2018 and 2021, among others at 0.8 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.0°C | 22.0°C | 22.4°C | 22.8°C | 22.6°C | +0.6°C |
| Avg High | 29.4°C | 29.2°C | 29.6°C | 30.0°C | 29.8°C | +0.4°C |
| Avg Low | 14.7°C | 14.8°C | 15.3°C | 15.6°C | 15.5°C | +0.8°C |
| Avg Rain | 76 mm | 93 mm | 84 mm | 78 mm | 74 mm | -3 mm |
December temperatures in Muswellbrook have risen by about 0.6°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 6.5°C (1995) to a record high of 41.1°C (2019).
Rainfall in December is a relatively wet time of year, averaging 82 mm, with a wettest year of 176 mm.
One of the best times to visit Muswellbrook
December is one of the best times to visit Muswellbrook. Expect days averaging 29.6°C and nights around 15.2°C (mean 22.4°C) — warmer than Muswellbrook's yearly average — with higher rainfall (82 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 | 31.8°C | 23.7°C | 15.7°C | 40.1°C | 8.4°C | 42 mm | 49% | 0.9 m/s | — |
| 2024 | 33.0°C | 25.2°C | 17.4°C | 38.9°C | 11.7°C | 39 mm | 52% | 0.9 m/s | 7.6 |
| 2023 | 32.1°C | 24.7°C | 17.3°C | 40.0°C | 13.6°C | 82 mm | 58% | 0.9 m/s | 7.1 |
| 2022 | 27.4°C | 20.1°C | 12.7°C | 34.5°C | 8.2°C | 42 mm | 57% | 0.9 m/s | 7.5 |
| 2021 | 26.2°C | 20.2°C | 14.3°C | 33.5°C | 8.0°C | 87 mm | 76% | 0.8 m/s | 6.9 |
| 2020 | 28.2°C | 21.9°C | 15.7°C | 40.4°C | 11.0°C | 150 mm | 66% | 1 m/s | 6 |
| 2019 | 33.3°C | 24.8°C | 16.3°C | 41.1°C | 10.0°C | 2 mm | 41% | 1 m/s | 7.7 |
| 2018 | 31.9°C | 24.1°C | 16.3°C | 38.9°C | 10.7°C | 78 mm | 56% | 0.8 m/s | 7.6 |
| 2017 | 31.7°C | 24.6°C | 17.5°C | 40.1°C | 12.6°C | 63 mm | 57% | 0.9 m/s | 6.7 |
| 2016 | 32.2°C | 24.9°C | 17.6°C | 38.6°C | 13.4°C | 67 mm | 54% | 0.9 m/s | 7.1 |
| 2015 | 29.3°C | 22.2°C | 15.0°C | 37.1°C | 10.2°C | 119 mm | 59% | 1 m/s | 7.1 |
| 2014 | 29.0°C | 22.5°C | 16.0°C | 34.2°C | 10.1°C | 155 mm | 64% | 0.9 m/s | 6.7 |
| 2013 | 30.8°C | 22.7°C | 14.6°C | 38.3°C | 7.8°C | 26 mm | 52% | 0.8 m/s | 7.8 |
| 2012 | 31.4°C | 23.3°C | 15.3°C | 39.1°C | 9.9°C | 77 mm | 55% | 0.9 m/s | 6.7 |
| 2011 ❄️ | 23.6°C | 18.0°C | 12.4°C | 30.9°C | 7.6°C | 78 mm | 74% | 0.9 m/s | 5.9 |
| 2010 | 26.5°C | 20.8°C | 15.1°C | 35.8°C | 8.1°C | 114 mm | 71% | 0.8 m/s | 6.2 |
| 2009 | 30.7°C | 23.6°C | 16.4°C | 39.3°C | 9.5°C | 100 mm | 56% | 0.9 m/s | 6.6 |
| 2008 | 28.5°C | 21.7°C | 15.0°C | 32.1°C | 11.0°C | 92 mm | 59% | 0.9 m/s | 7 |
| 2007 | 25.3°C | 20.0°C | 14.6°C | 29.3°C | 9.7°C | 133 mm | 77% | 0.8 m/s | 6.2 |
| 2006 | 29.4°C | 21.8°C | 14.2°C | 37.4°C | 7.2°C | 63 mm | 57% | 0.9 m/s | 6.8 |
| 2005 | 32.8°C | 24.3°C | 15.8°C | 40.7°C | 9.7°C | 25 mm | 47% | 0.9 m/s | 8.4 |
| 2004 | 28.7°C | 21.8°C | 15.0°C | 39.6°C | 8.9°C | 116 mm | 62% | 0.8 m/s | 7.1 |
| 2003 | 30.4°C | 23.2°C | 15.9°C | 39.3°C | 9.7°C | 71 mm | 61% | 0.9 m/s | 6.8 |
| 2002 | 29.0°C | 21.8°C | 14.7°C | 37.9°C | 9.0°C | 118 mm | 59% | 0.9 m/s | 7.3 |
| 2001 | 30.4°C | 22.8°C | 15.2°C | 37.0°C | 10.5°C | 55 mm | 51% | 0.9 m/s | 7.1 |
| 2000 | 30.4°C | 23.1°C | 15.8°C | 36.5°C | 9.7°C | 63 mm | 57% | 0.8 m/s | 7.5 |
| 1999 | 27.0°C | 20.3°C | 13.7°C | 34.0°C | 9.0°C | 77 mm | 63% | 0.8 m/s | 6.8 |
| 1998 | 30.5°C | 23.2°C | 15.8°C | 36.3°C | 9.1°C | 44 mm | 58% | 0.8 m/s | 7.4 |
| 1997 | 32.9°C | 25.2°C | 17.4°C | 39.0°C | 14.0°C | 55 mm | 51% | 0.9 m/s | 7.2 |
| 1996 | 28.8°C | 21.5°C | 14.1°C | 36.1°C | 9.8°C | 99 mm | 58% | 0.9 m/s | 7.2 |
| 1995 | 26.3°C | 19.6°C | 13.0°C | 33.1°C | 6.5°C | 131 mm | 66% | 0.8 m/s | 7 |
| 1994 | 30.8°C | 22.8°C | 14.8°C | 39.8°C | 8.1°C | 79 mm | 57% | 1 m/s | 7.5 |
| 1993 | 29.1°C | 21.7°C | 14.4°C | 37.9°C | 9.7°C | 54 mm | 57% | 1 m/s | 6.6 |
| 1992 🌧️ | 25.1°C | 19.6°C | 14.1°C | 30.2°C | 8.8°C | 176 mm | 74% | 0.8 m/s | 6.4 |
| 1991 | 26.8°C | 20.2°C | 13.7°C | 34.3°C | 10.7°C | 163 mm | 64% | 1 m/s | 6.5 |
| 1990 🔥 | 34.3°C | 25.7°C | 17.1°C | 40.8°C | 10.8°C | 55 mm | 49% | 0.9 m/s | 7.6 |
| 1989 | 28.8°C | 21.5°C | 14.3°C | 35.2°C | 9.6°C | 81 mm | 60% | 1 m/s | 7.4 |
| 1988 | 28.9°C | 22.4°C | 15.9°C | 35.8°C | 10.2°C | 117 mm | 66% | 1 m/s | 6.2 |
| 1987 | 29.2°C | 21.8°C | 14.5°C | 37.7°C | 7.6°C | 109 mm | 57% | 1 m/s | 6.9 |
| 1986 | 29.4°C | 21.4°C | 13.4°C | 37.5°C | 8.9°C | 21 mm | 50% | 0.9 m/s | 8 |
| 1985 | 28.5°C | 21.7°C | 14.8°C | 36.5°C | 9.2°C | 67 mm | 57% | 0.9 m/s | 7 |
| 1984 | 29.1°C | 21.4°C | 13.6°C | 37.1°C | 8.8°C | 65 mm | 50% | 0.9 m/s | 7.5 |
| 1983 | 28.1°C | 21.0°C | 14.0°C | 37.9°C | 9.6°C | 111 mm | 63% | 0.9 m/s | — |
| 1982 | 31.9°C | 23.9°C | 16.0°C | 38.6°C | 11.2°C | 40 mm | 49% | 0.9 m/s | — |
| 1981 | 30.8°C | 23.1°C | 15.4°C | 38.5°C | 9.2°C | 76 mm | 55% | 0.9 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 29.6°C with lows near 15.2°C (mean 22.4°C), based on 45 years of NASA POWER data.
December averages 82 mm of rainfall in Muswellbrook, a relatively wet time of year. The wettest on record was 176 mm in 1992.
The hottest December reached 41.1°C in 2019. The coldest dipped to 6.5°C in 1995.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 0.6°C. Daytime highs moved from 29.7°C to 30.1°C and overnight lows from 14.8°C to 15.5°C over the same span.
December is one of the warmer months of the year in Muswellbrook and a relatively wet time of year, so plan for around 29.6°C daytime highs and 15.2°C at night.
Not quite — December is the 10th coolest month in Muswellbrook, averaging 22.4°C.
For December in Muswellbrook, pack light layers you can adjust through the day, with typical highs of 29.6°C and lows of 15.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 58% — moderately humid.
Average wind speed in December is 0.9 m/s. The windiest December on record averaged 1 m/s (1987).
The wettest December on record was 1992 with 176 mm. On average, December sees 82 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 Muswellbrook 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.
