December is one of the cooler months of the year in Caledon, with average highs near -0.6°C and lows around -7°C (mean -3.8°C). It is about average for rainfall, averaging 53 mm of rainfall and 90% relative humidity across the period.
December is one of the cooler months of the year in Caledon. Across 45 years of records, the warmest December in Caledon was 2015 — when the month averaged 1.9°C — while the coldest was 1989 at -9.9°C. Typical December days reach -0.6°C with nights near -7°C. The long-term trend is warming, about 0.4°C per decade.
December is about average for rainfall in Caledon, averaging 53 mm of rainfall. The wettest December on record was 2008 with 102 mm, while the driest was 1994 at 12 mm.
Relative humidity in Caledon during December averages 90%. The most humid December was 1983 at 96%, and the least humid was 1988 at 82%.
December receives about 1.1 kWh/m²/day of solar energy in Caledon. The sunniest December was 1995 at 1.4 kWh/m²/day, and the cloudiest was 1984 at 0.9.
Average wind speed in Caledon during December is 3.5 m/s. The windiest December was 1988 at 4.2 m/s, while the calmest was 2023 at 2.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -4.9°C | -3.1°C | -4.6°C | -3.4°C | -2.7°C | +2.2°C |
| Avg High | -1.6°C | 0.1°C | -1.4°C | -0.4°C | 0.4°C | +2°C |
| Avg Low | -8.1°C | -6.4°C | -7.8°C | -6.4°C | -5.8°C | +2.3°C |
| Avg Rain | 46 mm | 31 mm | 67 mm | 59 mm | 70 mm | +24 mm |
December temperatures in Caledon have risen by about 2.1°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -26.4°C (1983) to a record high of 18.6°C (1982).
Rainfall in December is about average for rainfall, averaging 53 mm, with a wettest year of 102 mm.
A quieter season to visit Caledon
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Caledon. That said, December — with days averaging -0.6°C and nights around -7°C (mean -3.8°C) and moderate rainfall (53 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | -2.2°C | -6.4°C | -10.6°C | 5.1°C | -17.3°C | 75 mm | 89% | 4 m/s | — |
| 2024 | -0.1°C | -2.9°C | -5.8°C | 7.8°C | -14.9°C | 72 mm | 89% | 3.2 m/s | 1.1 |
| 2023 | 2.5°C | 0.1°C | -2.3°C | 9.2°C | -7.1°C | 74 mm | 90% | 2.7 m/s | 1 |
| 2022 | 0.2°C | -3.0°C | -6.1°C | 7.8°C | -15.0°C | 69 mm | 89% | 3.7 m/s | 1.1 |
| 2021 | 1.8°C | -1.4°C | -4.6°C | 14.1°C | -10.6°C | 60 mm | 89% | 3.6 m/s | 1.2 |
| 2020 | 0.3°C | -2.6°C | -5.6°C | 6.5°C | -10.7°C | 68 mm | 90% | 3.6 m/s | 1.2 |
| 2019 | 0.4°C | -2.9°C | -6.2°C | 6.1°C | -14.4°C | 51 mm | 90% | 3.4 m/s | 1.1 |
| 2018 | 0.1°C | -3.2°C | -6.4°C | 5.7°C | -12.1°C | 72 mm | 93% | 2.8 m/s | 1.1 |
| 2017 | -3.5°C | -6.2°C | -8.8°C | 9.4°C | -19.3°C | 39 mm | 87% | 3.5 m/s | 1.3 |
| 2016 | -1.0°C | -3.9°C | -6.8°C | 6.1°C | -18.2°C | 72 mm | 91% | 3.8 m/s | 1.1 |
| 2015 🔥 | 5.0°C | 1.9°C | -1.3°C | 14.5°C | -8.1°C | 74 mm | 91% | 3.4 m/s | 1.1 |
| 2014 | 0.1°C | -2.5°C | -5.1°C | 6.4°C | -11.6°C | 45 mm | 89% | 3.2 m/s | 1.2 |
| 2013 | -3.9°C | -6.9°C | -9.9°C | 6.6°C | -20.2°C | 60 mm | 92% | 3.1 m/s | 1.1 |
| 2012 | 1.2°C | -1.7°C | -4.6°C | 12.0°C | -9.2°C | 62 mm | 92% | 3.2 m/s | 1.1 |
| 2011 | 1.3°C | -2.1°C | -5.6°C | 9.5°C | -15.1°C | 61 mm | 91% | 3.1 m/s | 1.3 |
| 2010 | -3.8°C | -6.6°C | -9.5°C | 3.3°C | -16.5°C | 53 mm | 95% | 3.5 m/s | 1.1 |
| 2009 | -1.9°C | -5.1°C | -8.3°C | 7.5°C | -15.6°C | 60 mm | 91% | 3.3 m/s | 1.3 |
| 2008 🌧️ | -2.1°C | -6.0°C | -9.8°C | 8.7°C | -18.5°C | 102 mm | 93% | 4 m/s | 1.1 |
| 2007 | -2.2°C | -5.7°C | -9.2°C | 2.1°C | -18.5°C | 89 mm | 96% | 3.2 m/s | 1 |
| 2006 | 1.9°C | -1.1°C | -4.1°C | 8.1°C | -13.8°C | 73 mm | 92% | 3.6 m/s | 1.3 |
| 2005 | -2.8°C | -5.5°C | -8.2°C | 1.7°C | -15.4°C | 57 mm | 92% | 3.4 m/s | 1.1 |
| 2004 | -2.0°C | -5.7°C | -9.5°C | 7.0°C | -21.9°C | 93 mm | 93% | 3.8 m/s | 1.2 |
| 2003 | 0.1°C | -2.7°C | -5.6°C | 4.9°C | -13.2°C | 57 mm | 91% | 3.3 m/s | 1.3 |
| 2002 | -1.1°C | -4.5°C | -7.9°C | 3.9°C | -16.7°C | 35 mm | 90% | 3.6 m/s | 1.1 |
| 2001 | 1.9°C | -0.7°C | -3.3°C | 14.6°C | -9.8°C | 53 mm | 92% | 3.3 m/s | 1.3 |
| 2000 | -5.5°C | -8.6°C | -11.7°C | 1.1°C | -17.6°C | 52 mm | 93% | 3.4 m/s | 1.3 |
| 1999 | 0.4°C | -2.9°C | -6.2°C | 11.2°C | -14.3°C | 55 mm | 89% | 3.7 m/s | 1.1 |
| 1998 | 2.8°C | -1.1°C | -4.9°C | 15.4°C | -15.8°C | 57 mm | 87% | 3.6 m/s | 1.3 |
| 1997 | 0.4°C | -2.7°C | -5.7°C | 5.6°C | -13.8°C | 18 mm | 86% | 3.4 m/s | 1.2 |
| 1996 | -0.1°C | -2.9°C | -5.8°C | 8.6°C | -16.3°C | 56 mm | 92% | 3.2 m/s | 1 |
| 1995 | -3.7°C | -6.6°C | -9.5°C | 3.1°C | -14.5°C | 13 mm | 89% | 3.7 m/s | 1.4 |
| 1994 | 1.8°C | -1.4°C | -4.7°C | 8.0°C | -13.4°C | 12 mm | 87% | 2.9 m/s | 1 |
| 1993 | -0.9°C | -4.1°C | -7.3°C | 5.9°C | -19.0°C | 13 mm | 88% | 3.3 m/s | 1.1 |
| 1992 | 0.0°C | -2.9°C | -5.7°C | 5.7°C | -14.1°C | 23 mm | 88% | 3.6 m/s | 1 |
| 1991 | -0.2°C | -3.8°C | -7.4°C | 8.7°C | -15.9°C | 23 mm | 87% | 3.7 m/s | 1.1 |
| 1990 | 0.3°C | -3.1°C | -6.6°C | 6.0°C | -14.3°C | 37 mm | 87% | 3.9 m/s | 1.1 |
| 1989 ❄️ | -6.7°C | -9.9°C | -13.1°C | 2.3°C | -17.5°C | 14 mm | 84% | 3.4 m/s | 1.2 |
| 1988 | -0.9°C | -4.1°C | -7.4°C | 6.7°C | -16.1°C | 20 mm | 82% | 4.2 m/s | 1.1 |
| 1987 | 0.9°C | -2.2°C | -5.2°C | 7.8°C | -14.4°C | 25 mm | 86% | 3.8 m/s | 1.1 |
| 1986 | -0.3°C | -3.7°C | -7.2°C | 1.9°C | -15.9°C | 24 mm | 92% | 3.3 m/s | 1.1 |
| 1985 | -3.7°C | -6.5°C | -9.3°C | 5.7°C | -15.6°C | 28 mm | 91% | 3.8 m/s | 1 |
| 1984 | 1.2°C | -2.4°C | -5.9°C | 12.8°C | -13.6°C | 85 mm | 89% | 4 m/s | 0.9 |
| 1983 | -5.8°C | -9.4°C | -13.1°C | 1.3°C | -26.4°C | 99 mm | 96% | 3.8 m/s | — |
| 1982 | 2.4°C | -1.2°C | -4.7°C | 18.6°C | -20.1°C | 95 mm | 90% | 3.7 m/s | — |
| 1981 | -1.7°C | -4.5°C | -7.4°C | 3.2°C | -13.4°C | 22 mm | 91% | 3.2 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around -0.6°C with lows near -7°C (mean -3.8°C), based on 45 years of NASA POWER data.
December averages 53 mm of rainfall in Caledon, about average for rainfall. The wettest on record was 102 mm in 2008.
The hottest December reached 18.6°C in 1982. The coldest dipped to -26.4°C in 1983.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2.1°C. Daytime highs moved from -1.5°C to 0.4°C and overnight lows from -8.1°C to -5.9°C over the same span.
December is one of the cooler months of the year in Caledon and about average for rainfall, so plan for around -0.6°C daytime highs and -7°C at night.
Not quite — December is the 3rd coolest month in Caledon, averaging -3.8°C.
For December in Caledon, pack warm layers and a jacket for chilly mornings, with typical highs of -0.6°C and lows of -7°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 90% — quite humid.
Average wind speed in December is 3.5 m/s. The windiest December on record averaged 4.2 m/s (1988).
The wettest December on record was 2008 with 102 mm. On average, December sees 53 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 Caledon 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.
