December is one of the warmer months of the year in Penrith, with average highs near 28.4°C and lows around 14.4°C (mean 21.4°C). It is one of the drier months, averaging 79 mm of rainfall and 65% relative humidity across the period.
December is one of the warmer months of the year in Penrith. Across 45 years of records, the warmest December in Penrith was 1990 — when the month averaged 24.6°C — while the coldest was 2011 at 16.9°C. Typical December days reach 28.4°C with nights near 14.4°C. The long-term trend is warming, about 0.4°C per decade.
December is one of the drier months in Penrith, averaging 79 mm of rainfall. The wettest December on record was 1991 with 223 mm, while the driest was 2019 at 3 mm.
Relative humidity in Penrith during December averages 65%. The most humid December was 1992 at 81%, and the least humid was 2019 at 48%.
December receives about 6.6 kWh/m²/day of solar energy in Penrith. The sunniest December was 2005 at 8.4 kWh/m²/day, and the cloudiest was 2011 at 5.1.
Average wind speed in Penrith during December is 1.4 m/s. The windiest Decembers were 2002 and 2012 at 1.6 m/s, while the calmest were 2011, 2018 and 2021, among others at 1.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 20.6°C | 21.1°C | 21.8°C | 22.0°C | 21.7°C | +1.1°C |
| Avg High | 27.3°C | 28.0°C | 28.9°C | 28.9°C | 28.7°C | +1.4°C |
| Avg Low | 13.8°C | 14.1°C | 14.6°C | 15.0°C | 14.8°C | +1°C |
| Avg Rain | 87 mm | 85 mm | 68 mm | 78 mm | 75 mm | -12 mm |
December temperatures in Penrith have risen by about 0.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 5.7°C (2011) to a record high of 44.1°C (2019).
Rainfall in December is one of the drier months, averaging 79 mm, with a wettest year of 223 mm.
One of the best times to visit Penrith
December is one of the best times to visit Penrith. Expect days averaging 28.4°C and nights around 14.4°C (mean 21.4°C) — warmer than Penrith's yearly average — with moderate rainfall (79 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 | 31.3°C | 23.2°C | 15.1°C | 41.2°C | 8.3°C | 60 mm | 54% | 1.4 m/s | — |
| 2024 | 32.1°C | 24.2°C | 16.3°C | 41.0°C | 11.2°C | 41 mm | 61% | 1.4 m/s | 7.5 |
| 2023 | 29.9°C | 23.1°C | 16.3°C | 40.3°C | 12.4°C | 120 mm | 70% | 1.3 m/s | 6.5 |
| 2022 | 25.4°C | 18.8°C | 12.3°C | 34.3°C | 7.7°C | 37 mm | 67% | 1.3 m/s | 7 |
| 2021 | 26.0°C | 19.9°C | 13.9°C | 34.7°C | 9.2°C | 87 mm | 76% | 1.2 m/s | 6.3 |
| 2020 | 27.3°C | 21.0°C | 14.8°C | 39.2°C | 10.8°C | 105 mm | 68% | 1.5 m/s | 5.6 |
| 2019 | 32.3°C | 23.9°C | 15.4°C | 44.1°C | 9.5°C | 3 mm | 48% | 1.5 m/s | 7.2 |
| 2018 | 28.8°C | 22.1°C | 15.5°C | 38.4°C | 9.6°C | 136 mm | 70% | 1.2 m/s | 7 |
| 2017 | 31.2°C | 24.0°C | 16.7°C | 42.2°C | 12.2°C | 62 mm | 63% | 1.4 m/s | 6.3 |
| 2016 | 31.4°C | 24.2°C | 17.0°C | 38.1°C | 12.4°C | 73 mm | 60% | 1.4 m/s | 6.6 |
| 2015 | 29.8°C | 22.4°C | 15.0°C | 39.7°C | 11.1°C | 75 mm | 59% | 1.4 m/s | 6.7 |
| 2014 | 28.7°C | 22.2°C | 15.7°C | 35.7°C | 9.5°C | 132 mm | 67% | 1.3 m/s | 6.4 |
| 2013 | 28.9°C | 21.4°C | 14.0°C | 39.7°C | 7.6°C | 51 mm | 62% | 1.3 m/s | 7.5 |
| 2012 | 30.0°C | 22.4°C | 14.7°C | 38.9°C | 9.4°C | 43 mm | 60% | 1.6 m/s | 6.2 |
| 2011 ❄️ | 21.8°C | 16.9°C | 12.0°C | 28.8°C | 5.7°C | 99 mm | 80% | 1.2 m/s | 5.1 |
| 2010 | 26.0°C | 20.1°C | 14.2°C | 34.5°C | 8.0°C | 107 mm | 74% | 1.3 m/s | 6 |
| 2009 | 30.5°C | 22.9°C | 15.3°C | 41.2°C | 10.1°C | 71 mm | 60% | 1.5 m/s | 6.6 |
| 2008 | 28.5°C | 21.3°C | 14.1°C | 35.7°C | 9.5°C | 82 mm | 61% | 1.4 m/s | 6.8 |
| 2007 | 25.0°C | 19.7°C | 14.3°C | 31.3°C | 10.9°C | 114 mm | 78% | 1.2 m/s | 5.6 |
| 2006 | 28.1°C | 21.1°C | 14.0°C | 39.4°C | 7.0°C | 77 mm | 64% | 1.4 m/s | 6.2 |
| 2005 | 31.9°C | 23.3°C | 14.6°C | 40.3°C | 9.5°C | 29 mm | 54% | 1.3 m/s | 8.4 |
| 2004 | 27.8°C | 21.0°C | 14.2°C | 39.0°C | 8.3°C | 89 mm | 67% | 1.4 m/s | 6.7 |
| 2003 | 29.0°C | 22.1°C | 15.2°C | 39.8°C | 11.1°C | 53 mm | 67% | 1.3 m/s | 6.2 |
| 2002 | 29.1°C | 21.8°C | 14.4°C | 41.0°C | 8.8°C | 79 mm | 61% | 1.6 m/s | 6.8 |
| 2001 | 29.4°C | 21.9°C | 14.4°C | 38.0°C | 10.4°C | 39 mm | 58% | 1.3 m/s | 6.9 |
| 2000 | 30.1°C | 22.7°C | 15.2°C | 38.4°C | 8.1°C | 45 mm | 61% | 1.3 m/s | 7.3 |
| 1999 | 25.5°C | 19.5°C | 13.5°C | 33.6°C | 7.6°C | 90 mm | 70% | 1.3 m/s | 6.3 |
| 1998 | 28.7°C | 22.0°C | 15.4°C | 36.1°C | 10.8°C | 47 mm | 67% | 1.3 m/s | 6.8 |
| 1997 | 32.1°C | 24.2°C | 16.3°C | 39.7°C | 12.2°C | 36 mm | 56% | 1.4 m/s | 6.6 |
| 1996 | 28.6°C | 20.9°C | 13.2°C | 36.9°C | 8.8°C | 51 mm | 62% | 1.4 m/s | 6.7 |
| 1995 | 25.3°C | 18.7°C | 12.2°C | 31.5°C | 5.9°C | 78 mm | 70% | 1.3 m/s | 6.7 |
| 1994 | 29.6°C | 22.0°C | 14.3°C | 42.5°C | 7.7°C | 62 mm | 63% | 1.5 m/s | 6.9 |
| 1993 | 28.4°C | 21.2°C | 14.1°C | 39.3°C | 9.7°C | 46 mm | 62% | 1.5 m/s | 6.3 |
| 1992 | 23.6°C | 18.6°C | 13.5°C | 29.5°C | 8.9°C | 173 mm | 81% | 1.2 m/s | 5.7 |
| 1991 🌧️ | 24.8°C | 18.8°C | 12.7°C | 34.7°C | 6.7°C | 223 mm | 73% | 1.3 m/s | 6.1 |
| 1990 🔥 | 33.3°C | 24.6°C | 15.9°C | 40.5°C | 9.6°C | 46 mm | 56% | 1.5 m/s | 7.5 |
| 1989 | 27.2°C | 20.5°C | 13.7°C | 35.5°C | 8.5°C | 126 mm | 67% | 1.4 m/s | 6.8 |
| 1988 | 26.1°C | 20.5°C | 15.0°C | 33.1°C | 9.5°C | 129 mm | 76% | 1.3 m/s | 5.7 |
| 1987 | 26.4°C | 19.9°C | 13.4°C | 36.9°C | 6.8°C | 78 mm | 68% | 1.3 m/s | 6.4 |
| 1986 | 27.0°C | 19.8°C | 12.7°C | 35.1°C | 7.4°C | 28 mm | 62% | 1.4 m/s | 7.4 |
| 1985 | 26.6°C | 20.3°C | 14.0°C | 33.9°C | 9.7°C | 118 mm | 69% | 1.2 m/s | 6.8 |
| 1984 | 26.6°C | 19.7°C | 12.7°C | 38.0°C | 7.5°C | 88 mm | 60% | 1.3 m/s | 7.2 |
| 1983 | 26.0°C | 19.8°C | 13.6°C | 38.7°C | 7.4°C | 111 mm | 71% | 1.2 m/s | — |
| 1982 | 31.1°C | 23.0°C | 14.9°C | 40.2°C | 10.1°C | 23 mm | 54% | 1.5 m/s | — |
| 1981 | 29.0°C | 21.7°C | 14.3°C | 37.6°C | 9.6°C | 82 mm | 63% | 1.3 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 28.4°C with lows near 14.4°C (mean 21.4°C), based on 45 years of NASA POWER data.
December averages 79 mm of rainfall in Penrith, one of the drier months. The wettest on record was 223 mm in 1991.
The hottest December reached 44.1°C in 2019. The coldest dipped to 5.7°C in 2011.
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 27.9°C to 28.9°C and overnight lows from 13.9°C to 14.8°C over the same span.
December is one of the warmer months of the year in Penrith and one of the drier months, so plan for around 28.4°C daytime highs and 14.4°C at night.
Not quite — December is the 10th coolest month in Penrith, averaging 21.4°C.
For December in Penrith, pack light layers you can adjust through the day, with typical highs of 28.4°C and lows of 14.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 65% — moderately humid.
Average wind speed in December is 1.4 m/s. The windiest December on record averaged 1.6 m/s (2002).
The wettest December on record was 1991 with 223 mm. On average, December sees 79 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 Penrith 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.
