December is one of the warmer months of the year in Swan Hill, with average highs near 31°C and lows around 14.5°C (mean 22.8°C). It is about average for rainfall, averaging 32 mm of rainfall and 42% relative humidity across the period.
December is one of the warmer months of the year in Swan Hill. Across 45 years of records, the warmest December in Swan Hill was 2015 — when the month averaged 25.8°C — while the coldest was 2010 at 19.8°C. Typical December days reach 31°C with nights near 14.5°C. The long-term trend is warming, about 0.3°C per decade.
December is about average for rainfall in Swan Hill, averaging 32 mm of rainfall. The wettest December on record was 1992 with 123 mm, while the driest was 1984 at 2 mm.
Relative humidity in Swan Hill during December averages 42%. The most humid December was 1992 at 65%, and the least humid was 2015 at 30%.
December receives about 7.9 kWh/m²/day of solar energy in Swan Hill. The sunniest December was 1994 at 8.7 kWh/m²/day, and the cloudiest was 1992 at 6.6.
Average wind speed in Swan Hill during December is 3.6 m/s. The windiest December was 1984 at 4.2 m/s, while the calmest were 1992, 2010 and 2017 at 3.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.3°C | 22.4°C | 22.7°C | 23.6°C | 22.7°C | +0.4°C |
| Avg High | 30.5°C | 30.7°C | 31.1°C | 31.8°C | 31.0°C | +0.5°C |
| Avg Low | 14.2°C | 14.2°C | 14.3°C | 15.4°C | 14.4°C | +0.2°C |
| Avg Rain | 31 mm | 30 mm | 34 mm | 31 mm | 33 mm | +2 mm |
December temperatures in Swan Hill have risen by about 0.6°C between 1981–1985 and 2021–2025.
December has ranged from a record low of 6.6°C (1987) to a record high of 47°C (2019).
Rainfall in December is about average for rainfall, averaging 32 mm, with a wettest year of 123 mm.
One of the best times to visit Swan Hill
December is one of the best times to visit Swan Hill. Expect days averaging 31°C and nights around 14.5°C (mean 22.8°C) — warmer than Swan Hill's yearly average — with moderate rainfall (32 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 | 23.1°C | 14.4°C | 42.8°C | 7.6°C | 17 mm | 37% | 3.7 m/s | — |
| 2024 | 32.5°C | 24.0°C | 15.5°C | 43.8°C | 10.4°C | 22 mm | 44% | 3.4 m/s | 8.4 |
| 2023 | 30.4°C | 23.0°C | 15.5°C | 41.1°C | 10.3°C | 94 mm | 52% | 3.3 m/s | 7.2 |
| 2022 | 29.5°C | 21.4°C | 13.2°C | 40.5°C | 7.3°C | 9 mm | 50% | 3.3 m/s | 7.9 |
| 2021 | 31.9°C | 23.4°C | 14.9°C | 39.5°C | 8.8°C | 11 mm | 41% | 3.5 m/s | 8.5 |
| 2020 | 29.7°C | 21.4°C | 13.0°C | 38.6°C | 8.8°C | 45 mm | 43% | 3.8 m/s | 8.1 |
| 2019 | 34.2°C | 25.2°C | 16.3°C | 47.0°C | 8.5°C | 6 mm | 34% | 3.7 m/s | 8.3 |
| 2018 | 33.1°C | 25.2°C | 17.2°C | 43.1°C | 11.1°C | 49 mm | 44% | 3.3 m/s | 7.5 |
| 2017 | 30.6°C | 22.8°C | 15.0°C | 39.8°C | 8.4°C | 60 mm | 49% | 3.2 m/s | 7.5 |
| 2016 | 31.9°C | 23.9°C | 15.8°C | 39.2°C | 9.1°C | 16 mm | 40% | 3.5 m/s | 7.7 |
| 2015 🔥 | 34.5°C | 25.8°C | 17.1°C | 42.7°C | 8.9°C | 8 mm | 30% | 3.5 m/s | 8.4 |
| 2014 | 31.8°C | 23.9°C | 15.9°C | 37.8°C | 11.3°C | 18 mm | 38% | 3.3 m/s | 8.2 |
| 2013 | 32.0°C | 23.1°C | 14.3°C | 41.9°C | 6.7°C | 46 mm | 41% | 3.4 m/s | 7.7 |
| 2012 | 32.0°C | 23.6°C | 15.3°C | 41.3°C | 10.4°C | 13 mm | 37% | 3.8 m/s | 8.1 |
| 2011 | 30.8°C | 22.7°C | 14.6°C | 38.1°C | 7.9°C | 30 mm | 45% | 3.6 m/s | 8.3 |
| 2010 ❄️ | 26.7°C | 19.8°C | 12.9°C | 40.5°C | 7.0°C | 65 mm | 63% | 3.2 m/s | 7.6 |
| 2009 | 31.1°C | 22.3°C | 13.6°C | 40.9°C | 8.5°C | 24 mm | 44% | 3.3 m/s | 8.4 |
| 2008 | 28.3°C | 20.6°C | 12.9°C | 35.7°C | 8.6°C | 58 mm | 51% | 3.6 m/s | 7.6 |
| 2007 | 31.4°C | 23.5°C | 15.5°C | 41.8°C | 8.4°C | 52 mm | 44% | 3.3 m/s | 8 |
| 2006 | 31.7°C | 22.9°C | 14.1°C | 43.1°C | 7.6°C | 12 mm | 31% | 3.7 m/s | 8.3 |
| 2005 | 31.5°C | 23.0°C | 14.6°C | 46.0°C | 10.4°C | 28 mm | 40% | 3.9 m/s | 8 |
| 2004 | 29.5°C | 21.7°C | 14.0°C | 39.1°C | 8.0°C | 70 mm | 50% | 3.4 m/s | 7.9 |
| 2003 | 33.1°C | 24.7°C | 16.3°C | 42.4°C | 9.6°C | 51 mm | 44% | 3.3 m/s | 7.6 |
| 2002 | 32.6°C | 23.8°C | 15.0°C | 43.2°C | 7.1°C | 25 mm | 36% | 4 m/s | 7.8 |
| 2001 | 28.9°C | 20.9°C | 12.9°C | 39.0°C | 9.1°C | 4 mm | 40% | 3.8 m/s | 7.7 |
| 2000 | 32.4°C | 23.3°C | 14.3°C | 40.7°C | 8.8°C | 11 mm | 38% | 3.4 m/s | 8.4 |
| 1999 | 29.5°C | 21.6°C | 13.7°C | 38.4°C | 8.1°C | 43 mm | 46% | 3.8 m/s | 7.8 |
| 1998 | 32.0°C | 23.3°C | 14.6°C | 42.8°C | 8.4°C | 7 mm | 41% | 3.4 m/s | 8.5 |
| 1997 | 32.6°C | 24.1°C | 15.6°C | 39.1°C | 10.6°C | 6 mm | 36% | 3.5 m/s | 8.5 |
| 1996 | 30.4°C | 21.8°C | 13.2°C | 39.7°C | 8.8°C | 9 mm | 37% | 3.7 m/s | 7.9 |
| 1995 | 29.6°C | 20.9°C | 12.1°C | 37.5°C | 7.0°C | 12 mm | 40% | 3.8 m/s | 7.8 |
| 1994 | 34.2°C | 25.0°C | 15.7°C | 42.6°C | 8.3°C | 12 mm | 30% | 3.6 m/s | 8.7 |
| 1993 | 28.8°C | 20.9°C | 13.1°C | 38.1°C | 6.9°C | 42 mm | 49% | 3.9 m/s | 7.3 |
| 1992 🌧️ | 27.0°C | 20.7°C | 14.4°C | 34.3°C | 9.4°C | 123 mm | 65% | 3.2 m/s | 6.6 |
| 1991 | 29.5°C | 21.5°C | 13.6°C | 39.5°C | 8.6°C | 34 mm | 44% | 3.5 m/s | 7.6 |
| 1990 | 33.2°C | 24.6°C | 16.0°C | 42.1°C | 8.1°C | 12 mm | 36% | 3.8 m/s | 8 |
| 1989 | 32.0°C | 23.3°C | 14.7°C | 40.0°C | 9.1°C | 13 mm | 37% | 3.6 m/s | 8.1 |
| 1988 | 30.9°C | 23.2°C | 15.5°C | 40.2°C | 9.1°C | 63 mm | 51% | 3.4 m/s | 7.5 |
| 1987 | 31.1°C | 22.4°C | 13.7°C | 41.0°C | 6.6°C | 33 mm | 41% | 3.8 m/s | 8.3 |
| 1986 | 27.8°C | 20.0°C | 12.3°C | 38.9°C | 7.2°C | 37 mm | 49% | 3.8 m/s | 7.6 |
| 1985 | 28.0°C | 20.7°C | 13.4°C | 36.6°C | 9.5°C | 62 mm | 51% | 3.8 m/s | 7.6 |
| 1984 | 30.2°C | 21.8°C | 13.5°C | 39.8°C | 8.1°C | 2 mm | 36% | 4.2 m/s | 8 |
| 1983 | 31.6°C | 23.2°C | 14.7°C | 40.5°C | 8.7°C | 51 mm | 43% | 3.6 m/s | — |
| 1982 | 32.0°C | 23.8°C | 15.6°C | 39.5°C | 9.6°C | 9 mm | 34% | 3.6 m/s | — |
| 1981 | 31.3°C | 22.7°C | 14.0°C | 42.6°C | 8.5°C | 8 mm | 37% | 3.8 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 31°C with lows near 14.5°C (mean 22.8°C), based on 45 years of NASA POWER data.
December averages 32 mm of rainfall in Swan Hill, about average for rainfall. The wettest on record was 123 mm in 1992.
The hottest December reached 47°C in 2019. The coldest dipped to 6.6°C in 1987.
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 30.6°C to 31.2°C and overnight lows from 14.2°C to 14.7°C over the same span.
December is one of the warmer months of the year in Swan Hill and about average for rainfall, so plan for around 31°C daytime highs and 14.5°C at night.
Not quite — December is the 10th coolest month in Swan Hill, averaging 22.8°C.
For December in Swan Hill, pack light, breathable clothing and sun protection, with typical highs of 31°C and lows of 14.5°C.
Relative humidity in December averages 42% — relatively dry.
Average wind speed in December is 3.6 m/s. The windiest December on record averaged 4.2 m/s (1984).
The wettest December on record was 1992 with 123 mm. On average, December sees 32 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 Swan Hill 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.
