December is one of the cooler months of the year in Nanaimo, with average highs near 5.2°C and lows around 1.7°C (mean 3.5°C). It is a relatively wet time of year, averaging 132 mm of rainfall and 90% relative humidity across the period.
December is one of the cooler months of the year in Nanaimo. Across 45 years of records, the warmest December in Nanaimo was 2023 — when the month averaged 6.1°C — while the coldest was 1983 at -0.6°C. Typical December days reach 5.2°C with nights near 1.7°C. The long-term trend is warming, about 0.3°C per decade.
December is a relatively wet time of year in Nanaimo, averaging 132 mm of rainfall. The wettest December on record was 1998 with 239 mm, while the driest was 2013 at 42 mm.
Relative humidity in Nanaimo during December averages 90%. The most humid December was 2023 at 95%, and the least humid was 2009 at 83%.
December receives about 0.7 kWh/m²/day of solar energy in Nanaimo. The sunniest December was 2009 at 0.9 kWh/m²/day, and the cloudiest were 2006, 2012 and 2019 at 0.5.
Average wind speed in Nanaimo during December is 1.8 m/s. The windiest Decembers were 2010, 2015 and 2018, among others at 2.1 m/s, while the calmest was 1985 at 1.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 2.9°C | 3.2°C | 3.5°C | 3.7°C | 4.1°C | +1.2°C |
| Avg High | 4.6°C | 5.1°C | 5.2°C | 5.4°C | 5.9°C | +1.3°C |
| Avg Low | 1.1°C | 1.4°C | 1.7°C | 2.0°C | 2.4°C | +1.3°C |
| Avg Rain | 139 mm | 157 mm | 116 mm | 116 mm | 130 mm | -9 mm |
December temperatures in Nanaimo have risen by about 2°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -12°C (1990) to a record high of 14.6°C (2025).
Rainfall in December is a relatively wet time of year, averaging 132 mm, with a wettest year of 239 mm.
A quieter season to visit Nanaimo
If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Nanaimo. That said, December — with days averaging 5.2°C and nights around 1.7°C (mean 3.5°C) and higher rainfall (132 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 | 6.8°C | 5.2°C | 3.6°C | 14.6°C | -1.4°C | 143 mm | 93% | 1.8 m/s | — |
| 2024 | 6.8°C | 5.1°C | 3.5°C | 9.3°C | 1.3°C | 132 mm | 94% | 1.9 m/s | 0.7 |
| 2023 🔥 | 7.9°C | 6.1°C | 4.3°C | 10.8°C | 1.1°C | 134 mm | 95% | 1.6 m/s | 0.6 |
| 2022 | 4.1°C | 2.1°C | 0.2°C | 9.3°C | -8.9°C | 123 mm | 89% | 1.8 m/s | 0.8 |
| 2021 | 2.9°C | 1.1°C | -0.6°C | 11.6°C | -9.6°C | 106 mm | 86% | 1.9 m/s | 0.8 |
| 2020 | 6.8°C | 5.1°C | 3.3°C | 9.8°C | -0.5°C | 143 mm | 93% | 1.8 m/s | 0.7 |
| 2019 | 6.4°C | 4.9°C | 3.4°C | 10.8°C | 0.8°C | 99 mm | 94% | 1.5 m/s | 0.5 |
| 2018 | 7.0°C | 5.1°C | 3.3°C | 11.0°C | -0.4°C | 140 mm | 87% | 2.1 m/s | 0.7 |
| 2017 | 4.8°C | 2.9°C | 1.1°C | 8.7°C | -3.7°C | 100 mm | 88% | 1.4 m/s | 0.8 |
| 2016 | 3.2°C | 1.4°C | -0.4°C | 9.4°C | -5.9°C | 95 mm | 86% | 1.9 m/s | 0.7 |
| 2015 | 5.7°C | 4.1°C | 2.5°C | 10.9°C | -2.3°C | 177 mm | 91% | 2.1 m/s | 0.6 |
| 2014 | 6.6°C | 4.9°C | 3.2°C | 13.1°C | -3.8°C | 132 mm | 89% | 1.7 m/s | 0.8 |
| 2013 | 4.1°C | 2.4°C | 0.7°C | 9.2°C | -6.8°C | 42 mm | 85% | 1.5 m/s | 0.7 |
| 2012 | 5.1°C | 3.8°C | 2.4°C | 8.6°C | 0.2°C | 150 mm | 93% | 1.9 m/s | 0.5 |
| 2011 | 5.2°C | 3.6°C | 1.9°C | 9.8°C | -0.9°C | 62 mm | 90% | 1.5 m/s | 0.8 |
| 2010 | 5.6°C | 3.9°C | 2.3°C | 10.1°C | -3.1°C | 166 mm | 90% | 2.1 m/s | 0.6 |
| 2009 | 3.9°C | 2.1°C | 0.2°C | 9.2°C | -4.1°C | 48 mm | 83% | 1.6 m/s | 0.9 |
| 2008 | 2.9°C | 1.1°C | -0.6°C | 8.5°C | -10.0°C | 103 mm | 86% | 1.9 m/s | 0.7 |
| 2007 | 4.8°C | 3.1°C | 1.5°C | 11.1°C | -1.0°C | 142 mm | 91% | 2 m/s | 0.6 |
| 2006 | 5.7°C | 4.0°C | 2.4°C | 10.0°C | -0.5°C | 133 mm | 92% | 2 m/s | 0.5 |
| 2005 | 6.0°C | 4.3°C | 2.6°C | 12.5°C | -1.9°C | 119 mm | 88% | 1.6 m/s | 0.7 |
| 2004 | 6.4°C | 4.7°C | 3.0°C | 12.2°C | -0.1°C | 135 mm | 92% | 1.6 m/s | 0.7 |
| 2003 | 5.5°C | 3.7°C | 1.9°C | 8.8°C | -0.9°C | 121 mm | 93% | 1.9 m/s | 0.6 |
| 2002 | 6.8°C | 4.9°C | 3.1°C | 12.1°C | -1.5°C | 112 mm | 93% | 1.9 m/s | 0.6 |
| 2001 | 5.3°C | 3.5°C | 1.7°C | 9.1°C | -1.2°C | 144 mm | 91% | 2 m/s | 0.7 |
| 2000 | 4.9°C | 3.1°C | 1.4°C | 9.3°C | -4.5°C | 105 mm | 88% | 1.6 m/s | 0.7 |
| 1999 | 6.5°C | 4.7°C | 2.8°C | 11.4°C | 0.2°C | 152 mm | 91% | 1.7 m/s | 0.6 |
| 1998 🌧️ | 5.0°C | 3.2°C | 1.4°C | 10.7°C | -9.1°C | 239 mm | 91% | 2.1 m/s | 0.6 |
| 1997 | 6.7°C | 4.7°C | 2.8°C | 10.6°C | 0.4°C | 83 mm | 93% | 1.8 m/s | 0.7 |
| 1996 | 3.1°C | 1.1°C | -0.8°C | 7.4°C | -9.3°C | 221 mm | 90% | 2.1 m/s | 0.6 |
| 1995 | 5.4°C | 3.5°C | 1.7°C | 8.7°C | -5.5°C | 188 mm | 90% | 2 m/s | 0.7 |
| 1994 | 5.2°C | 3.5°C | 1.8°C | 10.7°C | -4.0°C | 156 mm | 90% | 1.9 m/s | 0.7 |
| 1993 | 6.1°C | 4.3°C | 2.5°C | 11.8°C | -1.0°C | 165 mm | 88% | 1.7 m/s | 0.7 |
| 1992 | 3.7°C | 1.8°C | 0.0°C | 8.6°C | -7.4°C | 104 mm | 88% | 2.1 m/s | 0.7 |
| 1991 | 6.6°C | 4.9°C | 3.1°C | 10.5°C | 0.5°C | 95 mm | 91% | 1.8 m/s | 0.6 |
| 1990 | 3.0°C | 0.6°C | -1.7°C | 9.8°C | -12.0°C | 162 mm | 87% | 2 m/s | 0.7 |
| 1989 | 6.7°C | 5.1°C | 3.4°C | 11.3°C | 0.5°C | 100 mm | 94% | 1.3 m/s | 0.6 |
| 1988 | 5.7°C | 4.1°C | 2.5°C | 10.0°C | -0.3°C | 133 mm | 89% | 1.5 m/s | 0.7 |
| 1987 | 4.9°C | 3.2°C | 1.5°C | 10.8°C | -2.4°C | 169 mm | 87% | 2 m/s | 0.7 |
| 1986 | 5.8°C | 4.0°C | 2.1°C | 9.3°C | -1.9°C | 144 mm | 91% | 1.6 m/s | 0.7 |
| 1985 | 4.0°C | 2.3°C | 0.6°C | 6.1°C | -8.6°C | 50 mm | 89% | 1.2 m/s | 0.7 |
| 1984 | 2.4°C | 0.5°C | -1.4°C | 5.1°C | -7.7°C | 145 mm | 87% | 1.6 m/s | 0.7 |
| 1983 ❄️ | 1.3°C | -0.6°C | -2.4°C | 6.5°C | -10.2°C | 102 mm | 84% | 1.9 m/s | — |
| 1982 | 5.4°C | 3.5°C | 1.6°C | 10.5°C | -1.9°C | 171 mm | 88% | 1.7 m/s | — |
| 1981 | 5.4°C | 3.7°C | 2.0°C | 10.5°C | -2.7°C | 236 mm | 90% | 2.1 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 5.2°C with lows near 1.7°C (mean 3.5°C), based on 45 years of NASA POWER data.
December averages 132 mm of rainfall in Nanaimo, a relatively wet time of year. The wettest on record was 239 mm in 1998.
The hottest December reached 14.6°C in 2025. The coldest dipped to -12°C in 1990.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2°C. Daytime highs moved from 3.7°C to 5.7°C and overnight lows from 0.1°C to 2.2°C over the same span.
December is one of the cooler months of the year in Nanaimo and a relatively wet time of year, so plan for around 5.2°C daytime highs and 1.7°C at night.
Yes — December is the coldest month of the year in Nanaimo, averaging 3.5°C.
For December in Nanaimo, pack warm layers and a jacket for chilly mornings, with typical highs of 5.2°C and lows of 1.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 90% — quite humid.
Average wind speed in December is 1.8 m/s. The windiest December on record averaged 2.1 m/s (1981).
The wettest December on record was 1998 with 239 mm. On average, December sees 132 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 Nanaimo 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.
