December is one of the warmer months of the year in Mandurah, with average highs near 24.7°C and lows around 17.5°C (mean 21.1°C). It is one of the drier months, averaging 11 mm of rainfall and 63% relative humidity across the period.
December is one of the warmer months of the year in Mandurah. Across 45 years of records, the warmest December in Mandurah was 2019 — when the month averaged 23.8°C — while the coldest was 2005 at 17.8°C. Typical December days reach 24.7°C with nights near 17.5°C. The long-term trend is warming, about 0.4°C per decade.
December is one of the drier months in Mandurah, averaging 11 mm of rainfall. The wettest December on record was 2011 with 47 mm, while the driest was 1994 at 0 mm.
Relative humidity in Mandurah during December averages 63%. The most humid December was 2005 at 73%, and the least humid were 2020 and 2023 at 59%.
December receives about 8.3 kWh/m²/day of solar energy in Mandurah. The sunniest Decembers were 2000 and 2020 at 8.8 kWh/m²/day, and the cloudiest was 2011 at 7.5.
Average wind speed in Mandurah during December is 5.8 m/s. The windiest December was 1996 at 6.5 m/s, while the calmest was 2012 at 5.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 20.2°C | 21.2°C | 20.6°C | 21.5°C | 22.2°C | +2°C |
| Avg High | 23.6°C | 25.0°C | 24.2°C | 25.1°C | 26.2°C | +2.6°C |
| Avg Low | 16.9°C | 17.4°C | 17.1°C | 17.9°C | 18.3°C | +1.4°C |
| Avg Rain | 10 mm | 9 mm | 10 mm | 18 mm | 6 mm | -4 mm |
December temperatures in Mandurah have risen by about 2.4°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 12.3°C (2002) to a record high of 38.2°C (2021).
Rainfall in December is one of the drier months, averaging 11 mm, with a wettest year of 47 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.5°C per decade while lows rose 0.3°C per decade, widening the gap between day and night.
One of the best times to visit Mandurah
December is one of the best times to visit Mandurah. Expect days averaging 24.7°C and nights around 17.5°C (mean 21.1°C) — warmer than Mandurah's yearly average — with low rainfall (11 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 | 26.2°C | 22.2°C | 18.2°C | 35.1°C | 15.3°C | 9 mm | 62% | 6 m/s | — |
| 2024 | 26.3°C | 22.4°C | 18.6°C | 35.7°C | 15.8°C | 9 mm | 62% | 6 m/s | 8.4 |
| 2023 | 26.8°C | 22.9°C | 18.9°C | 30.7°C | 15.0°C | 2 mm | 59% | 6 m/s | 8.4 |
| 2022 | 25.1°C | 21.4°C | 17.7°C | 31.5°C | 14.7°C | 5 mm | 62% | 5.8 m/s | 8.5 |
| 2021 | 26.5°C | 22.5°C | 18.5°C | 38.2°C | 14.7°C | 5 mm | 60% | 5.8 m/s | 8.4 |
| 2020 | 26.2°C | 22.0°C | 17.7°C | 34.0°C | 13.2°C | 6 mm | 59% | 5.6 m/s | 8.8 |
| 2019 🔥 | 27.4°C | 23.8°C | 20.1°C | 34.9°C | 15.0°C | 9 mm | 59% | 5.3 m/s | 8.4 |
| 2018 | 23.9°C | 20.7°C | 17.5°C | 31.2°C | 14.4°C | 9 mm | 65% | 5.5 m/s | 8.4 |
| 2017 | 25.2°C | 21.5°C | 17.9°C | 32.7°C | 14.7°C | 21 mm | 62% | 6.1 m/s | 8.3 |
| 2016 | 23.8°C | 20.3°C | 16.7°C | 34.4°C | 14.0°C | 14 mm | 64% | 6.2 m/s | 8.6 |
| 2015 | 24.6°C | 21.0°C | 17.5°C | 31.8°C | 14.9°C | 8 mm | 62% | 5.8 m/s | 8.4 |
| 2014 | 24.0°C | 20.3°C | 16.7°C | 33.1°C | 13.9°C | 1 mm | 64% | 6 m/s | 8.6 |
| 2013 | 25.1°C | 21.5°C | 17.9°C | 32.6°C | 13.7°C | 3 mm | 62% | 5.5 m/s | 8.4 |
| 2012 | 25.6°C | 22.0°C | 18.5°C | 34.7°C | 14.6°C | 42 mm | 66% | 5.2 m/s | 7.9 |
| 2011 🌧️ | 25.8°C | 22.1°C | 18.4°C | 33.9°C | 16.0°C | 47 mm | 65% | 5.6 m/s | 7.5 |
| 2010 | 25.1°C | 21.5°C | 17.8°C | 34.9°C | 14.0°C | 20 mm | 63% | 6.2 m/s | 7.8 |
| 2009 | 25.7°C | 21.5°C | 17.3°C | 34.1°C | 13.6°C | 1 mm | 59% | 6 m/s | 8.6 |
| 2008 | 23.0°C | 20.0°C | 17.0°C | 31.8°C | 14.6°C | 15 mm | 69% | 6 m/s | 8.3 |
| 2007 | 23.7°C | 20.2°C | 16.8°C | 34.7°C | 12.5°C | 38 mm | 65% | 6.2 m/s | 7.7 |
| 2006 | 25.7°C | 21.8°C | 17.9°C | 32.0°C | 14.2°C | 6 mm | 61% | 5.5 m/s | 8.4 |
| 2005 ❄️ | 19.8°C | 17.8°C | 15.8°C | 24.0°C | 13.3°C | 15 mm | 73% | 5.7 m/s | 7.7 |
| 2004 | 25.3°C | 21.4°C | 17.5°C | 35.1°C | 13.7°C | 5 mm | 63% | 5.6 m/s | 8.4 |
| 2003 | 23.9°C | 20.3°C | 16.8°C | 33.5°C | 13.5°C | 3 mm | 67% | 6.2 m/s | 8.5 |
| 2002 | 26.0°C | 22.0°C | 18.0°C | 36.1°C | 12.3°C | 3 mm | 62% | 5.7 m/s | 8.2 |
| 2001 | 23.2°C | 19.5°C | 15.9°C | 27.1°C | 13.2°C | 10 mm | 65% | 6.2 m/s | 8.3 |
| 2000 | 25.5°C | 21.6°C | 17.6°C | 34.6°C | 14.3°C | 2 mm | 63% | 6.2 m/s | 8.8 |
| 1999 | 27.2°C | 23.1°C | 19.0°C | 34.2°C | 14.6°C | 11 mm | 60% | 5.6 m/s | 8.4 |
| 1998 | 25.4°C | 21.7°C | 18.0°C | 33.9°C | 14.3°C | 15 mm | 64% | 5.6 m/s | 8.2 |
| 1997 | 25.9°C | 22.0°C | 18.0°C | 36.1°C | 14.8°C | 1 mm | 63% | 5.9 m/s | 8.5 |
| 1996 | 24.2°C | 20.4°C | 16.6°C | 32.3°C | 14.3°C | 18 mm | 64% | 6.5 m/s | 8.3 |
| 1995 | 24.6°C | 20.8°C | 17.1°C | 29.9°C | 13.4°C | 14 mm | 65% | 6.1 m/s | 8.2 |
| 1994 | 26.0°C | 22.0°C | 18.1°C | 33.4°C | 13.6°C | 0 mm | 60% | 5.7 m/s | 8.5 |
| 1993 | 25.0°C | 20.7°C | 16.4°C | 34.2°C | 13.6°C | 3 mm | 60% | 6.3 m/s | 8.7 |
| 1992 | 23.9°C | 20.2°C | 16.5°C | 33.1°C | 13.6°C | 7 mm | 65% | 5.9 m/s | 8.2 |
| 1991 | 24.2°C | 20.7°C | 17.2°C | 34.1°C | 13.9°C | 16 mm | 68% | 5.4 m/s | 8.1 |
| 1990 | 23.4°C | 20.3°C | 17.1°C | 32.6°C | 14.3°C | 6 mm | 65% | 6.1 m/s | 8.2 |
| 1989 | 23.4°C | 20.2°C | 16.9°C | 33.7°C | 14.5°C | 9 mm | 64% | 6 m/s | 8.1 |
| 1988 | 25.0°C | 21.0°C | 17.1°C | 29.7°C | 13.3°C | 6 mm | 64% | 5.8 m/s | 8.5 |
| 1987 | 24.3°C | 20.9°C | 17.5°C | 37.0°C | 13.2°C | 18 mm | 65% | 5.5 m/s | 7.9 |
| 1986 | 24.2°C | 20.4°C | 16.6°C | 31.3°C | 12.5°C | 14 mm | 61% | 5.9 m/s | 8.2 |
| 1985 | 22.2°C | 19.2°C | 16.3°C | 30.0°C | 13.5°C | 4 mm | 63% | 5.7 m/s | 8.3 |
| 1984 | 21.8°C | 18.9°C | 16.1°C | 27.6°C | 13.0°C | 16 mm | 66% | 5.8 m/s | 7.7 |
| 1983 | 24.7°C | 21.0°C | 17.4°C | 33.5°C | 13.5°C | 12 mm | 66% | 5.4 m/s | — |
| 1982 | 23.6°C | 20.9°C | 18.2°C | 32.1°C | 14.0°C | 11 mm | 68% | 5.5 m/s | — |
| 1981 | 23.1°C | 19.7°C | 16.2°C | 30.3°C | 13.0°C | 5 mm | 63% | 6.1 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 24.7°C with lows near 17.5°C (mean 21.1°C), based on 45 years of NASA POWER data.
December averages 11 mm of rainfall in Mandurah, one of the drier months. The wettest on record was 47 mm in 2011.
The hottest December reached 38.2°C in 2021. The coldest dipped to 12.3°C in 2002.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2.4°C. Daytime highs moved from 23.1°C to 26.2°C and overnight lows from 16.8°C to 18.4°C over the same span.
December is one of the warmer months of the year in Mandurah and one of the drier months, so plan for around 24.7°C daytime highs and 17.5°C at night.
Not quite — December is the 9th coolest month in Mandurah, averaging 21.1°C.
For December in Mandurah, pack light layers you can adjust through the day, with typical highs of 24.7°C and lows of 17.5°C.
Relative humidity in December averages 63% — moderately humid.
Average wind speed in December is 5.8 m/s. The windiest December on record averaged 6.5 m/s (1996).
The wettest December on record was 2011 with 47 mm. On average, December sees 11 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 Mandurah 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.
