December is one of the cooler months of the year in Moncton, with average highs near -0.8°C and lows around -8.9°C (mean -4.9°C). It is about average for rainfall, averaging 98 mm of rainfall and 90% relative humidity across the period.
December is one of the cooler months of the year in Moncton. Across 45 years of records, the warmest December in Moncton was 2023 — when the month averaged -1°C — while the coldest was 1989 at -15.3°C. Typical December days reach -0.8°C with nights near -8.9°C. The long-term trend is warming, about 0.7°C per decade.
December is about average for rainfall in Moncton, averaging 98 mm of rainfall. The wettest December on record was 2014 with 179 mm, while the driest was 2001 at 46 mm.
Relative humidity in Moncton during December averages 90%. The most humid December was 1989 at 100%, and the least humid was 2025 at 82%.
December receives about 1.1 kWh/m²/day of solar energy in Moncton. The sunniest Decembers were 1995 and 2001 at 1.3 kWh/m²/day, and the cloudiest were 1993 and 2013 at 0.8.
Average wind speed in Moncton during December is 0.1 m/s. The windiest Decembers were 2018, 2024 and 2025, among others at 0.2 m/s, while the calmest were 2021, 2022 and 2023, among others at 0.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -6.8°C | -4.8°C | -4.9°C | -4.3°C | -2.6°C | +4.2°C |
| Avg High | -2.4°C | -0.7°C | -0.9°C | -0.4°C | 1.3°C | +3.7°C |
| Avg Low | -11.3°C | -9.0°C | -8.9°C | -8.1°C | -6.5°C | +4.8°C |
| Avg Rain | 92 mm | 95 mm | 105 mm | 111 mm | 79 mm | -13 mm |
December temperatures in Moncton have risen by about 2.4°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -33.3°C (1989) to a record high of 15.4°C (2020).
Rainfall in December is about average for rainfall, averaging 98 mm, with a wettest year of 179 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.6°C per decade while lows rose 0.9°C per decade, narrowing the gap between day and night.
A quieter season to visit Moncton
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Moncton. That said, December — with days averaging -0.8°C and nights around -8.9°C (mean -4.9°C) and higher rainfall (98 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 | -1.8°C | -6.0°C | -10.2°C | 14.0°C | -20.1°C | 58 mm | 82% | 0.2 m/s | — |
| 2024 | 0.5°C | -3.4°C | -7.4°C | 13.8°C | -17.1°C | 57 mm | 88% | 0.2 m/s | 1.2 |
| 2023 🔥 | 2.8°C | -1.0°C | -4.8°C | 15.2°C | -12.6°C | 65 mm | 87% | 0.1 m/s | 1.1 |
| 2022 | 1.9°C | -1.6°C | -5.0°C | 10.7°C | -12.4°C | 107 mm | 88% | 0.1 m/s | 1 |
| 2021 | 1.5°C | -2.6°C | -6.8°C | 13.4°C | -14.7°C | 58 mm | 82% | 0.1 m/s | 1.2 |
| 2020 | 2.6°C | -1.2°C | -4.9°C | 15.4°C | -17.0°C | 130 mm | 90% | 0.1 m/s | 1 |
| 2019 | 0.2°C | -4.0°C | -8.2°C | 12.4°C | -16.0°C | 78 mm | 87% | 0.1 m/s | 1.2 |
| 2018 | -2.8°C | -7.2°C | -11.6°C | 11.6°C | -21.8°C | 70 mm | 92% | 0.2 m/s | 1.2 |
| 2017 | -2.8°C | -6.7°C | -10.5°C | 9.5°C | -22.8°C | 81 mm | 88% | 0.1 m/s | 1.1 |
| 2016 | -2.2°C | -6.4°C | -10.5°C | 7.6°C | -26.4°C | 89 mm | 93% | 0.2 m/s | 1 |
| 2015 | 1.3°C | -1.7°C | -4.7°C | 9.3°C | -17.6°C | 123 mm | 95% | 0.1 m/s | 1 |
| 2014 🌧️ | 1.7°C | -2.1°C | -5.8°C | 13.9°C | -17.0°C | 179 mm | 86% | 0.2 m/s | 1 |
| 2013 | -4.2°C | -8.0°C | -11.8°C | 5.1°C | -24.2°C | 140 mm | 92% | 0.1 m/s | 0.8 |
| 2012 | 0.5°C | -3.4°C | -7.2°C | 8.8°C | -15.9°C | 116 mm | 91% | 0.2 m/s | 1.1 |
| 2011 | 2.3°C | -2.0°C | -6.4°C | 14.1°C | -15.7°C | 99 mm | 88% | 0.1 m/s | 1.1 |
| 2010 | 1.9°C | -1.2°C | -4.4°C | 13.9°C | -17.4°C | 140 mm | 92% | 0.1 m/s | 1 |
| 2009 | -1.7°C | -4.9°C | -8.1°C | 11.7°C | -19.2°C | 113 mm | 94% | 0.2 m/s | 1 |
| 2008 | 1.1°C | -3.6°C | -8.3°C | 12.4°C | -18.8°C | 168 mm | 86% | 0.1 m/s | 1 |
| 2007 | -3.5°C | -8.2°C | -12.8°C | 8.1°C | -23.5°C | 108 mm | 96% | 0.2 m/s | 1 |
| 2006 | 0.4°C | -3.2°C | -6.9°C | 10.9°C | -18.9°C | 89 mm | 89% | 0.1 m/s | 1.1 |
| 2005 | -1.0°C | -4.4°C | -7.7°C | 10.4°C | -15.6°C | 101 mm | 90% | 0.2 m/s | 1.1 |
| 2004 | -1.5°C | -6.1°C | -10.7°C | 9.3°C | -20.6°C | 108 mm | 88% | 0.1 m/s | 1.1 |
| 2003 | 0.1°C | -3.5°C | -7.1°C | 9.9°C | -14.9°C | 121 mm | 86% | 0.1 m/s | 1 |
| 2002 | -2.2°C | -6.3°C | -10.3°C | 5.5°C | -19.6°C | 94 mm | 92% | 0.1 m/s | 1.2 |
| 2001 | 1.4°C | -2.0°C | -5.4°C | 11.8°C | -11.5°C | 46 mm | 87% | 0.1 m/s | 1.3 |
| 2000 | -2.4°C | -6.9°C | -11.3°C | 12.0°C | -19.2°C | 104 mm | 88% | 0.2 m/s | 1.2 |
| 1999 | 0.6°C | -3.1°C | -6.7°C | 10.9°C | -17.4°C | 99 mm | 88% | 0.1 m/s | 1 |
| 1998 | 0.4°C | -3.8°C | -8.1°C | 10.4°C | -20.6°C | 65 mm | 86% | 0.1 m/s | 1.1 |
| 1997 | -2.2°C | -6.7°C | -11.3°C | 1.9°C | -23.6°C | 73 mm | 96% | 0.2 m/s | 1.1 |
| 1996 | 1.9°C | -1.6°C | -5.1°C | 11.8°C | -22.1°C | 118 mm | 89% | 0.1 m/s | 1 |
| 1995 | -3.1°C | -6.9°C | -10.7°C | 2.6°C | -21.4°C | 77 mm | 91% | 0.2 m/s | 1.3 |
| 1994 | -1.6°C | -5.7°C | -9.8°C | 5.3°C | -19.5°C | 72 mm | 93% | 0.2 m/s | 1 |
| 1993 | -0.3°C | -4.0°C | -7.7°C | 13.4°C | -28.5°C | 119 mm | 87% | 0.2 m/s | 0.8 |
| 1992 | -1.0°C | -4.9°C | -8.8°C | 5.0°C | -20.0°C | 79 mm | 91% | 0.2 m/s | 1 |
| 1991 | -2.8°C | -7.9°C | -13.0°C | 10.0°C | -24.5°C | 67 mm | 91% | 0.1 m/s | 1.1 |
| 1990 | 0.8°C | -3.7°C | -8.3°C | 13.1°C | -18.5°C | 178 mm | 89% | 0.1 m/s | 1 |
| 1989 ❄️ | -10.2°C | -15.3°C | -20.4°C | 0.0°C | -33.3°C | 65 mm | 100% | 0.1 m/s | 1.2 |
| 1988 | -2.4°C | -6.7°C | -10.9°C | 6.5°C | -20.7°C | 48 mm | 84% | 0.1 m/s | 1.1 |
| 1987 | -3.2°C | -7.3°C | -11.3°C | 10.2°C | -24.4°C | 130 mm | 96% | 0.1 m/s | 1.1 |
| 1986 | -1.1°C | -6.0°C | -11.0°C | 9.8°C | -21.8°C | 49 mm | 88% | 0.2 m/s | 1.1 |
| 1985 | -3.2°C | -8.3°C | -13.4°C | 9.9°C | -27.5°C | 62 mm | 89% | 0.2 m/s | 1.2 |
| 1984 | -0.2°C | -4.8°C | -9.3°C | 7.5°C | -24.5°C | 94 mm | 87% | 0.1 m/s | 0.9 |
| 1983 | -2.1°C | -6.3°C | -10.5°C | 9.5°C | -22.5°C | 132 mm | 86% | 0.1 m/s | — |
| 1982 | 0.9°C | -3.5°C | -7.9°C | 13.0°C | -22.6°C | 88 mm | 88% | 0.2 m/s | — |
| 1981 | 0.1°C | -3.4°C | -6.8°C | 10.6°C | -20.3°C | 158 mm | 95% | 0.1 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around -0.8°C with lows near -8.9°C (mean -4.9°C), based on 45 years of NASA POWER data.
December averages 98 mm of rainfall in Moncton, about average for rainfall. The wettest on record was 179 mm in 2014.
The hottest December reached 15.4°C in 2020. The coldest dipped to -33.3°C in 1989.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 2.4°C. Daytime highs moved from -0.9°C to 1°C and overnight lows from -9.6°C to -6.8°C over the same span.
December is one of the cooler months of the year in Moncton and about average for rainfall, so plan for around -0.8°C daytime highs and -8.9°C at night.
Not quite — December is the 3rd coolest month in Moncton, averaging -4.9°C.
For December in Moncton, pack warm layers and a jacket for chilly mornings, with typical highs of -0.8°C and lows of -8.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 90% — quite humid.
Average wind speed in December is 0.1 m/s. The windiest December on record averaged 0.2 m/s (1982).
The wettest December on record was 2014 with 179 mm. On average, December sees 98 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 Moncton 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.
