December is one of the cooler months of the year in Calgary, with average highs near -3.5°C and lows around -11.8°C (mean -7.6°C). It is one of the drier months, averaging 19 mm of rainfall and 81% relative humidity across the period.
December is one of the cooler months of the year in Calgary. Across 45 years of records, the warmest December in Calgary was 1999 — when the month averaged -2°C — while the coldest was 1983 at -16.3°C. Typical December days reach -3.5°C with nights near -11.8°C. The long-term trend is warming, about 0.3°C per decade.
December is one of the drier months in Calgary, averaging 19 mm of rainfall. The wettest December on record was 2017 with 49 mm, while the driest was 1986 at 3 mm.
Relative humidity in Calgary during December averages 81%. The most humid December was 1996 at 94%, and the least humid was 1997 at 65%.
December receives about 0.9 kWh/m²/day of solar energy in Calgary. The sunniest Decembers were 1997 and 2002 at 1 kWh/m²/day, and the cloudiest was 1989 at 0.7.
Average wind speed in Calgary during December is 1.6 m/s. The windiest Decembers were 1990 and 2011 at 2.1 m/s, while the calmest was 2010 at 1.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -8.2°C | -7.7°C | -7.5°C | -7.8°C | -6.8°C | +1.4°C |
| Avg High | -4.1°C | -3.5°C | -3.3°C | -3.7°C | -2.9°C | +1.2°C |
| Avg Low | -12.2°C | -11.8°C | -11.7°C | -11.9°C | -10.8°C | +1.4°C |
| Avg Rain | 13 mm | 15 mm | 18 mm | 22 mm | 34 mm | +21 mm |
December temperatures in Calgary have risen by about 2.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -36.2°C (1992) to a record high of 9.8°C (2002).
Rainfall in December is one of the drier months, averaging 19 mm, with a wettest year of 49 mm.
A quieter season to visit Calgary
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Calgary. That said, December — with days averaging -3.5°C and nights around -11.8°C (mean -7.6°C) and low rainfall (19 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 | -6.5°C | -10.9°C | 4.8°C | -25.6°C | 43 mm | 90% | 1.6 m/s | — |
| 2024 | -0.8°C | -4.1°C | -7.4°C | 2.4°C | -16.5°C | 19 mm | 88% | 1.4 m/s | 0.9 |
| 2023 | 1.1°C | -2.6°C | -6.3°C | 7.3°C | -13.7°C | 36 mm | 83% | 1.6 m/s | 0.8 |
| 2022 | -7.5°C | -11.9°C | -16.4°C | 2.4°C | -34.0°C | 27 mm | 89% | 1.4 m/s | 0.9 |
| 2021 | -7.6°C | -11.8°C | -16.0°C | 6.8°C | -31.9°C | 29 mm | 79% | 1.5 m/s | 0.8 |
| 2020 | -0.4°C | -4.2°C | -8.0°C | 6.9°C | -17.5°C | 47 mm | 82% | 1.7 m/s | 0.9 |
| 2019 | -2.0°C | -6.0°C | -9.9°C | 3.4°C | -16.2°C | 20 mm | 88% | 1.6 m/s | 0.9 |
| 2018 | -1.0°C | -5.1°C | -9.2°C | 4.4°C | -16.5°C | 14 mm | 77% | 1.6 m/s | 0.9 |
| 2017 🌧️ | -4.7°C | -8.8°C | -13.0°C | 6.5°C | -32.8°C | 49 mm | 75% | 1.7 m/s | 0.9 |
| 2016 | -8.8°C | -12.2°C | -15.7°C | 1.1°C | -25.1°C | 29 mm | 81% | 1.8 m/s | 0.9 |
| 2015 | -2.6°C | -6.8°C | -11.1°C | 3.9°C | -22.0°C | 21 mm | 85% | 1.4 m/s | 0.9 |
| 2014 | -1.9°C | -5.9°C | -10.0°C | 3.0°C | -24.2°C | 10 mm | 84% | 1.5 m/s | 0.9 |
| 2013 | -5.5°C | -9.8°C | -14.1°C | 3.3°C | -30.0°C | 29 mm | 86% | 1.8 m/s | 0.8 |
| 2012 | -5.7°C | -10.0°C | -14.2°C | 1.6°C | -25.6°C | 22 mm | 89% | 1.4 m/s | 0.9 |
| 2011 | -1.0°C | -4.9°C | -8.8°C | 3.7°C | -17.2°C | 19 mm | 77% | 2.1 m/s | 0.8 |
| 2010 | -4.2°C | -8.7°C | -13.2°C | 1.5°C | -24.1°C | 11 mm | 88% | 1.3 m/s | 0.9 |
| 2009 | -7.6°C | -12.0°C | -16.3°C | 2.3°C | -26.9°C | 21 mm | 80% | 1.6 m/s | 0.9 |
| 2008 | -8.7°C | -13.4°C | -18.1°C | 6.7°C | -34.0°C | 43 mm | 90% | 1.5 m/s | 0.8 |
| 2007 | -4.5°C | -8.9°C | -13.3°C | 0.1°C | -21.4°C | 17 mm | 85% | 1.5 m/s | 0.8 |
| 2006 | -0.6°C | -4.4°C | -8.1°C | 3.3°C | -17.4°C | 11 mm | 78% | 1.7 m/s | 0.9 |
| 2005 | -2.0°C | -5.7°C | -9.4°C | 6.5°C | -21.3°C | 10 mm | 80% | 1.5 m/s | 0.9 |
| 2004 | -1.2°C | -5.2°C | -9.1°C | 6.5°C | -22.9°C | 27 mm | 79% | 1.9 m/s | 0.8 |
| 2003 | -1.2°C | -5.3°C | -9.4°C | 4.1°C | -17.9°C | 5 mm | 79% | 1.7 m/s | 0.9 |
| 2002 | 0.5°C | -3.8°C | -8.1°C | 9.8°C | -14.9°C | 15 mm | 78% | 1.4 m/s | 1 |
| 2001 | -2.7°C | -7.5°C | -12.3°C | 2.5°C | -17.7°C | 9 mm | 82% | 1.5 m/s | 0.9 |
| 2000 | -4.8°C | -8.9°C | -13.1°C | 5.2°C | -26.2°C | 18 mm | 81% | 1.5 m/s | 0.8 |
| 1999 🔥 | 1.8°C | -2.0°C | -5.8°C | 8.9°C | -13.5°C | 10 mm | 71% | 1.8 m/s | 0.8 |
| 1998 | -4.7°C | -8.7°C | -12.7°C | 6.9°C | -26.3°C | 19 mm | 78% | 1.7 m/s | 0.8 |
| 1997 | 1.0°C | -2.9°C | -6.8°C | 4.6°C | -13.4°C | 3 mm | 65% | 1.9 m/s | 1 |
| 1996 | -10.3°C | -15.0°C | -19.6°C | -1.1°C | -33.5°C | 28 mm | 94% | 1.4 m/s | 0.8 |
| 1995 | -4.5°C | -8.7°C | -12.9°C | 1.4°C | -28.0°C | 31 mm | 87% | 1.5 m/s | 0.9 |
| 1994 | -2.8°C | -7.1°C | -11.3°C | 3.4°C | -22.5°C | 13 mm | 81% | 1.5 m/s | 0.9 |
| 1993 | -0.5°C | -4.4°C | -8.3°C | 6.1°C | -14.3°C | 10 mm | 79% | 1.7 m/s | 0.9 |
| 1992 | -7.7°C | -12.4°C | -17.2°C | 0.7°C | -36.2°C | 20 mm | 81% | 1.5 m/s | 0.9 |
| 1991 | 0.3°C | -3.4°C | -7.1°C | 5.3°C | -12.5°C | 3 mm | 73% | 1.9 m/s | 0.8 |
| 1990 | -7.9°C | -12.3°C | -16.6°C | 3.5°C | -34.5°C | 16 mm | 80% | 2.1 m/s | 0.8 |
| 1989 | -2.3°C | -5.9°C | -9.5°C | 4.9°C | -29.1°C | 20 mm | 80% | 1.8 m/s | 0.7 |
| 1988 | -2.3°C | -6.5°C | -10.6°C | 6.6°C | -20.4°C | 12 mm | 75% | 1.6 m/s | 0.8 |
| 1987 | -1.3°C | -5.0°C | -8.7°C | 5.1°C | -18.4°C | 11 mm | 71% | 1.6 m/s | 0.8 |
| 1986 | -0.3°C | -4.5°C | -8.8°C | 2.8°C | -14.6°C | 3 mm | 73% | 1.9 m/s | 0.9 |
| 1985 | -1.7°C | -5.5°C | -9.2°C | 4.3°C | -27.7°C | 7 mm | 80% | 2 m/s | 0.9 |
| 1984 | -9.6°C | -14.2°C | -18.8°C | 2.0°C | -33.7°C | 20 mm | 83% | 1.6 m/s | 0.9 |
| 1983 ❄️ | -11.9°C | -16.3°C | -20.8°C | -2.6°C | -34.8°C | 19 mm | 86% | 1.5 m/s | — |
| 1982 | -3.4°C | -7.5°C | -11.5°C | 2.3°C | -18.3°C | 18 mm | 86% | 1.6 m/s | — |
| 1981 | -4.0°C | -8.1°C | -12.2°C | 3.9°C | -24.9°C | 7 mm | 78% | 1.4 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around -3.5°C with lows near -11.8°C (mean -7.6°C), based on 45 years of NASA POWER data.
December averages 19 mm of rainfall in Calgary, one of the drier months. The wettest on record was 49 mm in 2017.
The hottest December reached 9.8°C in 2002. The coldest dipped to -36.2°C in 1992.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2.9°C. Daytime highs moved from -6.1°C to -3.4°C and overnight lows from -14.5°C to -11.4°C over the same span.
December is one of the cooler months of the year in Calgary and one of the drier months, so plan for around -3.5°C daytime highs and -11.8°C at night.
Yes — December is the coldest month of the year in Calgary, averaging -7.6°C.
For December in Calgary, pack warm layers and a jacket for chilly mornings, with typical highs of -3.5°C and lows of -11.8°C.
Relative humidity in December averages 81% — quite humid.
Average wind speed in December is 1.6 m/s. The windiest December on record averaged 2.1 m/s (1990).
The wettest December on record was 2017 with 49 mm. On average, December sees 19 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 Calgary 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.
