December is one of the cooler months of the year in Summerland, with average highs near -4.8°C and lows around -12.6°C (mean -8.7°C). It is a relatively wet time of year, averaging 60 mm of rainfall and 98% relative humidity across the period.
December is one of the cooler months of the year in Summerland. Across 45 years of records, the warmest December in Summerland was 2023 — when the month averaged -4.7°C — while the coldest was 1983 at -15.3°C. Typical December days reach -4.8°C with nights near -12.6°C. The long-term trend is warming, about 0.6°C per decade.
December is a relatively wet time of year in Summerland, averaging 60 mm of rainfall. The wettest December on record was 2025 with 109 mm, while the driest was 1985 at 22 mm.
Relative humidity in Summerland during December averages 98%. The most humid December was 2006 at 100%, and the least humid was 2021 at 95%.
December receives about 0.8 kWh/m²/day of solar energy in Summerland. The sunniest Decembers were 2011, 2017 and 2020, among others at 0.9 kWh/m²/day, and the cloudiest were 2012 and 2019 at 0.6.
Average wind speed in Summerland during December is 0.3 m/s. The windiest Decembers were 2016, 2017 and 2018, among others at 0.4 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -10.0°C | -8.9°C | -8.3°C | -8.3°C | -7.6°C | +2.4°C |
| Avg High | -5.7°C | -5.0°C | -4.5°C | -4.4°C | -4.0°C | +1.7°C |
| Avg Low | -14.2°C | -12.9°C | -12.1°C | -12.2°C | -11.2°C | +3°C |
| Avg Rain | 49 mm | 59 mm | 59 mm | 61 mm | 75 mm | +26 mm |
December temperatures in Summerland have risen by about 3.7°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -39.5°C (1990) to a record high of 6.2°C (2021).
Rainfall in December is a relatively wet time of year, averaging 60 mm, with a wettest year of 109 mm.
A quieter season to visit Summerland
If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Summerland. That said, December — with days averaging -4.8°C and nights around -12.6°C (mean -8.7°C) and moderate rainfall (60 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 🌧️ | -2.3°C | -5.2°C | -8.1°C | 0.3°C | -20.9°C | 109 mm | 99% | 0.3 m/s | — |
| 2024 | -3.0°C | -6.6°C | -10.2°C | 0.1°C | -15.4°C | 82 mm | 99% | 0.3 m/s | 0.7 |
| 2023 🔥 | -1.7°C | -4.7°C | -7.7°C | 0.7°C | -17.5°C | 72 mm | 99% | 0.3 m/s | 0.7 |
| 2022 | -7.7°C | -12.1°C | -16.4°C | 0.3°C | -35.8°C | 57 mm | 99% | 0.3 m/s | 0.8 |
| 2021 | -6.9°C | -11.1°C | -15.3°C | 6.2°C | -35.0°C | 60 mm | 95% | 0.3 m/s | 0.8 |
| 2020 | -2.6°C | -6.0°C | -9.4°C | 0.8°C | -15.6°C | 73 mm | 98% | 0.3 m/s | 0.9 |
| 2019 | -2.6°C | -6.0°C | -9.4°C | 1.5°C | -17.7°C | 80 mm | 99% | 0.3 m/s | 0.6 |
| 2018 | -3.3°C | -6.9°C | -10.4°C | 0.4°C | -19.1°C | 55 mm | 98% | 0.4 m/s | 0.8 |
| 2017 | -6.1°C | -10.7°C | -15.3°C | -0.2°C | -28.3°C | 79 mm | 99% | 0.4 m/s | 0.9 |
| 2016 | -8.3°C | -13.0°C | -17.7°C | -0.8°C | -30.4°C | 50 mm | 98% | 0.4 m/s | 0.8 |
| 2015 | -4.6°C | -8.3°C | -12.0°C | 0.5°C | -24.0°C | 76 mm | 99% | 0.4 m/s | 0.7 |
| 2014 | -2.4°C | -6.0°C | -9.6°C | 2.6°C | -25.4°C | 60 mm | 97% | 0.3 m/s | 0.8 |
| 2013 | -5.4°C | -9.3°C | -13.3°C | 1.1°C | -32.3°C | 48 mm | 97% | 0.4 m/s | 0.8 |
| 2012 | -3.9°C | -7.5°C | -11.1°C | 0.9°C | -16.8°C | 77 mm | 99% | 0.4 m/s | 0.6 |
| 2011 | -3.2°C | -6.9°C | -10.7°C | 1.1°C | -16.1°C | 29 mm | 97% | 0.3 m/s | 0.9 |
| 2010 | -4.2°C | -8.2°C | -12.3°C | 0.5°C | -25.8°C | 53 mm | 98% | 0.4 m/s | 0.8 |
| 2009 | -7.0°C | -11.5°C | -16.1°C | 0.1°C | -28.3°C | 38 mm | 97% | 0.4 m/s | 0.9 |
| 2008 | -8.1°C | -12.3°C | -16.5°C | 3.2°C | -33.8°C | 68 mm | 97% | 0.3 m/s | 0.8 |
| 2007 | -4.0°C | -7.6°C | -11.1°C | 2.6°C | -17.8°C | 68 mm | 96% | 0.3 m/s | 0.7 |
| 2006 | -4.3°C | -7.9°C | -11.4°C | 0.1°C | -17.3°C | 74 mm | 100% | 0.3 m/s | 0.7 |
| 2005 | -4.4°C | -8.1°C | -11.8°C | 0.3°C | -20.3°C | 49 mm | 98% | 0.4 m/s | 0.8 |
| 2004 | -2.1°C | -5.6°C | -9.2°C | 0.8°C | -16.6°C | 67 mm | 98% | 0.3 m/s | 0.8 |
| 2003 | -4.1°C | -7.9°C | -11.8°C | 0.1°C | -20.1°C | 46 mm | 99% | 0.4 m/s | 0.8 |
| 2002 | -1.6°C | -5.2°C | -8.7°C | 4.3°C | -16.5°C | 83 mm | 96% | 0.3 m/s | 0.8 |
| 2001 | -4.3°C | -8.2°C | -12.1°C | 0.0°C | -17.2°C | 64 mm | 99% | 0.4 m/s | 0.9 |
| 2000 | -4.7°C | -8.4°C | -12.2°C | 0.5°C | -21.8°C | 36 mm | 96% | 0.3 m/s | 0.8 |
| 1999 | -2.3°C | -6.1°C | -9.9°C | 0.6°C | -14.9°C | 45 mm | 98% | 0.3 m/s | 0.7 |
| 1998 | -5.5°C | -8.7°C | -11.9°C | 0.7°C | -32.1°C | 74 mm | 98% | 0.3 m/s | 0.7 |
| 1997 | -2.0°C | -5.4°C | -8.9°C | 2.3°C | -14.0°C | 30 mm | 95% | 0.3 m/s | 0.8 |
| 1996 | -8.0°C | -12.2°C | -16.3°C | 0.1°C | -32.8°C | 81 mm | 99% | 0.3 m/s | 0.8 |
| 1995 | -4.7°C | -8.7°C | -12.8°C | 0.2°C | -27.1°C | 76 mm | 97% | 0.3 m/s | 0.9 |
| 1994 | -5.3°C | -9.3°C | -13.3°C | 0.0°C | -28.3°C | 59 mm | 99% | 0.3 m/s | 0.8 |
| 1993 | -3.8°C | -7.4°C | -11.1°C | 0.3°C | -17.8°C | 69 mm | 99% | 0.3 m/s | 0.7 |
| 1992 | -7.8°C | -12.1°C | -16.4°C | 0.1°C | -28.7°C | 52 mm | 99% | 0.3 m/s | 0.8 |
| 1991 | -2.6°C | -6.3°C | -10.0°C | 0.9°C | -16.7°C | 32 mm | 99% | 0.3 m/s | 0.7 |
| 1990 | -8.4°C | -13.2°C | -18.0°C | 0.3°C | -39.5°C | 74 mm | 99% | 0.3 m/s | 0.8 |
| 1989 | -2.0°C | -5.4°C | -8.8°C | 0.8°C | -16.7°C | 40 mm | 98% | 0.3 m/s | 0.7 |
| 1988 | -4.7°C | -8.9°C | -13.2°C | 0.0°C | -25.3°C | 52 mm | 98% | 0.3 m/s | 0.8 |
| 1987 | -5.5°C | -9.6°C | -13.6°C | 0.6°C | -23.2°C | 82 mm | 99% | 0.3 m/s | 0.8 |
| 1986 | -3.8°C | -7.9°C | -11.9°C | 0.1°C | -17.0°C | 32 mm | 98% | 0.3 m/s | 0.8 |
| 1985 | -4.7°C | -9.0°C | -13.3°C | 0.1°C | -30.5°C | 22 mm | 99% | 0.4 m/s | 0.9 |
| 1984 | -9.5°C | -14.6°C | -19.6°C | -0.8°C | -33.8°C | 46 mm | 99% | 0.4 m/s | 0.9 |
| 1983 ❄️ | -10.3°C | -15.3°C | -20.4°C | -2.4°C | -37.7°C | 46 mm | 100% | 0.4 m/s | — |
| 1982 | -5.6°C | -9.4°C | -13.2°C | 0.2°C | -21.3°C | 60 mm | 99% | 0.4 m/s | — |
| 1981 | -5.5°C | -9.6°C | -13.6°C | 0.2°C | -24.4°C | 67 mm | 99% | 0.4 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around -4.8°C with lows near -12.6°C (mean -8.7°C), based on 45 years of NASA POWER data.
December averages 60 mm of rainfall in Summerland, a relatively wet time of year. The wettest on record was 109 mm in 2025.
The hottest December reached 6.2°C in 2021. The coldest dipped to -39.5°C in 1990.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 3.7°C. Daytime highs moved from -7.1°C to -4.3°C and overnight lows from -16°C to -11.5°C over the same span.
December is one of the cooler months of the year in Summerland and a relatively wet time of year, so plan for around -4.8°C daytime highs and -12.6°C at night.
Yes — December is the coldest month of the year in Summerland, averaging -8.7°C.
For December in Summerland, pack warm layers and a jacket for chilly mornings, with typical highs of -4.8°C and lows of -12.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 98% — quite humid.
Average wind speed in December is 0.3 m/s. The windiest December on record averaged 0.4 m/s (1981).
The wettest December on record was 2025 with 109 mm. On average, December sees 60 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 Summerland 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.
