December is one of the cooler months of the year in Truro, with average highs near 0.7°C and lows around -6.1°C (mean -2.7°C). It is about average for rainfall, averaging 84 mm of rainfall and 88% relative humidity across the period.
December is one of the cooler months of the year in Truro. Across 45 years of records, the warmest December in Truro was 2010 — when the month averaged 0.8°C — while the coldest was 1989 at -10.8°C. Typical December days reach 0.7°C with nights near -6.1°C. The long-term trend is warming, about 0.5°C per decade.
December is about average for rainfall in Truro, averaging 84 mm of rainfall. The wettest December on record was 2008 with 168 mm, while the driest was 1989 at 20 mm.
Relative humidity in Truro during December averages 88%. The most humid December was 2013 at 93%, and the least humid was 2021 at 83%.
December receives about 1.1 kWh/m²/day of solar energy in Truro. The sunniest Decembers were 1989 and 1995 at 1.3 kWh/m²/day, and the cloudiest was 1993 at 0.8.
Average wind speed in Truro during December is 0.7 m/s. The windiest Decembers were 2009, 2010 and 2025, among others at 0.8 m/s, while the calmest were 2018, 2021 and 2022, among others at 0.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | -4.2°C | -2.6°C | -2.9°C | -2.2°C | -1.2°C | +3°C |
| Avg High | -0.5°C | 0.9°C | 0.4°C | 1.1°C | 2.2°C | +2.7°C |
| Avg Low | -7.9°C | -6.0°C | -6.2°C | -5.5°C | -4.5°C | +3.4°C |
| Avg Rain | 61 mm | 78 mm | 108 mm | 96 mm | 72 mm | +11 mm |
December temperatures in Truro have risen by about 1.4°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -23.9°C (2016) to a record high of 14.7°C (2008).
Rainfall in December is about average for rainfall, averaging 84 mm, with a wettest year of 168 mm.
A quieter season to visit Truro
If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Truro. That said, December — with days averaging 0.7°C and nights around -6.1°C (mean -2.7°C) and higher rainfall (84 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 | -0.3°C | -3.9°C | -7.5°C | 12.7°C | -14.6°C | 61 mm | 84% | 0.8 m/s | — |
| 2024 | 1.4°C | -1.8°C | -5.1°C | 13.9°C | -11.9°C | 59 mm | 89% | 0.7 m/s | 1.1 |
| 2023 | 2.8°C | -0.1°C | -3.1°C | 13.1°C | -9.0°C | 82 mm | 91% | 0.7 m/s | 1.1 |
| 2022 | 2.8°C | -0.1°C | -3.0°C | 12.1°C | -9.6°C | 83 mm | 87% | 0.5 m/s | 1 |
| 2021 | 2.3°C | -1.5°C | -5.3°C | 13.7°C | -13.6°C | 62 mm | 83% | 0.5 m/s | 1.1 |
| 2020 | 4.0°C | 0.5°C | -3.0°C | 14.7°C | -12.3°C | 85 mm | 89% | 0.6 m/s | 1 |
| 2019 | 0.9°C | -2.7°C | -6.2°C | 12.7°C | -11.6°C | 61 mm | 86% | 0.6 m/s | 1.1 |
| 2018 | -1.5°C | -5.1°C | -8.6°C | 10.8°C | -15.4°C | 74 mm | 89% | 0.5 m/s | 1.1 |
| 2017 | -0.6°C | -4.0°C | -7.4°C | 12.6°C | -18.0°C | 84 mm | 85% | 0.6 m/s | 1.1 |
| 2016 | -0.4°C | -4.1°C | -7.8°C | 11.0°C | -23.9°C | 89 mm | 90% | 0.6 m/s | 1 |
| 2015 | 2.8°C | 0.1°C | -2.7°C | 9.6°C | -12.4°C | 116 mm | 93% | 0.7 m/s | 1 |
| 2014 | 3.1°C | -0.2°C | -3.6°C | 12.1°C | -15.4°C | 136 mm | 87% | 0.7 m/s | 1 |
| 2013 | -2.2°C | -5.7°C | -9.2°C | 8.6°C | -18.4°C | 118 mm | 93% | 0.7 m/s | 0.9 |
| 2012 | 2.3°C | -1.0°C | -4.3°C | 11.4°C | -10.0°C | 88 mm | 90% | 0.7 m/s | 1 |
| 2011 | 3.4°C | -0.1°C | -3.5°C | 14.5°C | -10.5°C | 82 mm | 87% | 0.7 m/s | 1 |
| 2010 🔥 | 3.2°C | 0.8°C | -1.6°C | 12.1°C | -9.5°C | 111 mm | 92% | 0.8 m/s | 1 |
| 2009 | 0.1°C | -2.7°C | -5.5°C | 12.0°C | -14.2°C | 111 mm | 91% | 0.8 m/s | 1 |
| 2008 🌧️ | 2.6°C | -1.6°C | -5.8°C | 14.7°C | -16.7°C | 168 mm | 86% | 0.8 m/s | 1 |
| 2007 | -1.5°C | -5.1°C | -8.7°C | 7.9°C | -15.9°C | 98 mm | 91% | 0.8 m/s | 1 |
| 2006 | 0.9°C | -2.3°C | -5.6°C | 10.9°C | -13.8°C | 101 mm | 87% | 0.5 m/s | 1.1 |
| 2005 | 0.7°C | -2.3°C | -5.3°C | 10.9°C | -11.4°C | 109 mm | 90% | 0.7 m/s | 1 |
| 2004 | 0.1°C | -3.7°C | -7.4°C | 11.0°C | -18.1°C | 122 mm | 87% | 0.7 m/s | 1 |
| 2003 | 1.3°C | -1.7°C | -4.6°C | 10.5°C | -12.3°C | 102 mm | 87% | 0.7 m/s | 1.1 |
| 2002 | -0.5°C | -3.9°C | -7.2°C | 8.7°C | -15.7°C | 92 mm | 90% | 0.7 m/s | 1.1 |
| 2001 | 1.7°C | -1.1°C | -3.9°C | 13.5°C | -8.3°C | 53 mm | 90% | 0.6 m/s | 1.1 |
| 2000 | -1.1°C | -4.8°C | -8.5°C | 11.7°C | -17.0°C | 120 mm | 88% | 0.7 m/s | 1.2 |
| 1999 | 2.2°C | -1.3°C | -4.7°C | 11.9°C | -14.5°C | 112 mm | 88% | 0.6 m/s | 0.9 |
| 1998 | 1.3°C | -2.3°C | -5.9°C | 10.8°C | -15.7°C | 45 mm | 85% | 0.7 m/s | 1.1 |
| 1997 | -0.4°C | -3.6°C | -6.8°C | 8.3°C | -16.6°C | 67 mm | 91% | 0.7 m/s | 1.2 |
| 1996 | 3.3°C | -0.1°C | -3.5°C | 11.6°C | -18.7°C | 100 mm | 88% | 0.6 m/s | 1 |
| 1995 | -1.4°C | -4.2°C | -7.1°C | 6.9°C | -13.9°C | 62 mm | 87% | 0.6 m/s | 1.3 |
| 1994 | 0.0°C | -3.4°C | -6.7°C | 6.9°C | -14.0°C | 77 mm | 88% | 0.6 m/s | 1 |
| 1993 | 1.5°C | -1.9°C | -5.3°C | 12.1°C | -23.1°C | 78 mm | 87% | 0.6 m/s | 0.8 |
| 1992 | 0.1°C | -3.2°C | -6.6°C | 9.1°C | -17.0°C | 70 mm | 87% | 0.7 m/s | 1 |
| 1991 | -0.7°C | -4.6°C | -8.5°C | 10.8°C | -18.5°C | 55 mm | 88% | 0.6 m/s | 1.1 |
| 1990 | 2.7°C | -1.1°C | -4.9°C | 13.0°C | -14.5°C | 113 mm | 86% | 0.6 m/s | 0.9 |
| 1989 ❄️ | -7.0°C | -10.8°C | -14.7°C | 3.2°C | -22.9°C | 20 mm | 87% | 0.7 m/s | 1.3 |
| 1988 | -1.1°C | -4.8°C | -8.4°C | 5.9°C | -17.1°C | 24 mm | 83% | 0.6 m/s | 1.1 |
| 1987 | -1.4°C | -4.3°C | -7.1°C | 11.4°C | -18.9°C | 51 mm | 91% | 0.7 m/s | 1.2 |
| 1986 | 0.3°C | -3.8°C | -7.8°C | 9.4°C | -17.9°C | 22 mm | 83% | 0.7 m/s | 1.1 |
| 1985 | -1.4°C | -5.8°C | -10.3°C | 10.1°C | -18.7°C | 34 mm | 86% | 0.6 m/s | 1.1 |
| 1984 | 1.5°C | -2.7°C | -6.8°C | 8.2°C | -21.2°C | 99 mm | 85% | 0.6 m/s | 1 |
| 1983 | -0.1°C | -3.7°C | -7.2°C | 10.3°C | -17.7°C | 127 mm | 87% | 0.7 m/s | — |
| 1982 | 1.9°C | -2.0°C | -5.8°C | 12.9°C | -20.2°C | 104 mm | 89% | 0.7 m/s | — |
| 1981 | 2.5°C | -0.2°C | -2.9°C | 13.5°C | -9.9°C | 66 mm | 89% | 0.6 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 0.7°C with lows near -6.1°C (mean -2.7°C), based on 45 years of NASA POWER data.
December averages 84 mm of rainfall in Truro, about average for rainfall. The wettest on record was 168 mm in 2008.
The hottest December reached 14.7°C in 2008. The coldest dipped to -23.9°C in 2016.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.4°C. Daytime highs moved from 0.9°C to 1.8°C and overnight lows from -6.6°C to -4.8°C over the same span.
December is one of the cooler months of the year in Truro and about average for rainfall, so plan for around 0.7°C daytime highs and -6.1°C at night.
Not quite — December is the 3rd coolest month in Truro, averaging -2.7°C.
For December in Truro, pack warm layers and a jacket for chilly mornings, with typical highs of 0.7°C and lows of -6.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 88% — quite humid.
Average wind speed in December is 0.7 m/s. The windiest December on record averaged 0.8 m/s (2007).
The wettest December on record was 2008 with 168 mm. On average, December sees 84 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 Truro 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.
