December is one of the cooler months of the year in Harwich, with average highs near 7.6°C and lows around 3.8°C (mean 5.7°C). It is a relatively wet time of year, averaging 68 mm of rainfall and 92% relative humidity across the period.
December is one of the cooler months of the year in Harwich. Across 45 years of records, the warmest December in Harwich was 2015 — when the month averaged 9.9°C — while the coldest was 2010 at 1.3°C. Typical December days reach 7.6°C with nights near 3.8°C. The long-term trend is warming, about 0.4°C per decade.
December is a relatively wet time of year in Harwich, averaging 68 mm of rainfall. The wettest December on record was 2020 with 131 mm, while the driest was 1988 at 22 mm.
Relative humidity in Harwich during December averages 92%. The most humid December was 2016 at 95%, and the least humid was 1996 at 87%.
December receives about 0.6 kWh/m²/day of solar energy in Harwich. The sunniest Decembers were 2016, 2019 and 2022, among others at 0.7 kWh/m²/day, and the cloudiest was 2002 at 0.4.
Average wind speed in Harwich during December is 4.8 m/s. The windiest December was 2015 at 6.2 m/s, while the calmest was 2016 at 3.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 5.5°C | 5.1°C | 5.5°C | 6.0°C | 6.7°C | +1.2°C |
| Avg High | 7.4°C | 7.0°C | 7.4°C | 7.9°C | 8.5°C | +1.1°C |
| Avg Low | 3.6°C | 3.2°C | 3.7°C | 4.1°C | 4.9°C | +1.3°C |
| Avg Rain | 61 mm | 65 mm | 60 mm | 74 mm | 83 mm | +22 mm |
December temperatures in Harwich have risen by about 1.9°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -4.1°C (1981) to a record high of 13.6°C (1986).
Rainfall in December is a relatively wet time of year, averaging 68 mm, with a wettest year of 131 mm.
A quieter season to visit Harwich
If your dates are flexible, the more temperate months of August and July tend to be the most comfortable for visiting Harwich. That said, December — with days averaging 7.6°C and nights around 3.8°C (mean 5.7°C) and moderate rainfall (68 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 | 9.3°C | 7.6°C | 5.8°C | 12.7°C | 0.7°C | 58 mm | 91% | 5.1 m/s | — |
| 2024 | 8.8°C | 7.0°C | 5.1°C | 12.9°C | 1.6°C | 47 mm | 93% | 5 m/s | 0.6 |
| 2023 | 9.2°C | 7.4°C | 5.7°C | 13.1°C | -0.2°C | 107 mm | 92% | 5.7 m/s | 0.6 |
| 2022 | 7.2°C | 5.3°C | 3.5°C | 12.3°C | -2.5°C | 68 mm | 92% | 4.5 m/s | 0.7 |
| 2021 | 8.6°C | 6.7°C | 4.8°C | 13.4°C | 0.7°C | 90 mm | 93% | 4.5 m/s | 0.5 |
| 2020 🌧️ | 7.8°C | 6.1°C | 4.3°C | 12.5°C | -0.5°C | 131 mm | 94% | 4.4 m/s | 0.6 |
| 2019 | 8.7°C | 6.8°C | 4.9°C | 12.3°C | 1.2°C | 117 mm | 93% | 5.1 m/s | 0.7 |
| 2018 | 8.9°C | 7.0°C | 5.2°C | 13.2°C | 0.8°C | 83 mm | 92% | 4.5 m/s | 0.6 |
| 2017 | 7.1°C | 5.0°C | 3.0°C | 11.2°C | -0.7°C | 101 mm | 94% | 5 m/s | 0.6 |
| 2016 | 8.5°C | 6.6°C | 4.8°C | 12.1°C | 0.7°C | 23 mm | 95% | 3.7 m/s | 0.7 |
| 2015 🔥 | 11.6°C | 9.9°C | 8.2°C | 13.5°C | 4.1°C | 69 mm | 91% | 6.2 m/s | 0.5 |
| 2014 | 7.7°C | 5.5°C | 3.4°C | 12.7°C | -0.8°C | 61 mm | 92% | 5.4 m/s | 0.7 |
| 2013 | 8.6°C | 6.5°C | 4.4°C | 11.9°C | 0.8°C | 66 mm | 93% | 5.4 m/s | 0.6 |
| 2012 | 7.2°C | 5.3°C | 3.3°C | 11.4°C | -1.4°C | 106 mm | 93% | 5.2 m/s | 0.6 |
| 2011 | 8.0°C | 5.9°C | 3.8°C | 11.7°C | -1.7°C | 83 mm | 91% | 5.8 m/s | 0.7 |
| 2010 ❄️ | 3.0°C | 1.3°C | -0.4°C | 6.8°C | -3.5°C | 35 mm | 92% | 4 m/s | 0.5 |
| 2009 | 6.3°C | 4.6°C | 2.9°C | 12.2°C | -2.4°C | 89 mm | 91% | 4.6 m/s | 0.7 |
| 2008 | 6.1°C | 4.4°C | 2.7°C | 10.5°C | -0.6°C | 33 mm | 94% | 4.1 m/s | 0.7 |
| 2007 | 8.1°C | 5.9°C | 3.7°C | 13.0°C | 0.7°C | 47 mm | 92% | 4.9 m/s | 0.7 |
| 2006 | 9.3°C | 7.5°C | 5.7°C | 13.2°C | 1.3°C | 71 mm | 91% | 5.2 m/s | 0.6 |
| 2005 | 6.9°C | 5.1°C | 3.2°C | 10.0°C | -1.3°C | 43 mm | 93% | 4.6 m/s | 0.7 |
| 2004 | 7.4°C | 5.4°C | 3.4°C | 11.5°C | -1.3°C | 38 mm | 93% | 3.9 m/s | 0.6 |
| 2003 | 7.7°C | 5.7°C | 3.7°C | 12.1°C | 0.3°C | 64 mm | 92% | 4.5 m/s | 0.6 |
| 2002 | 7.9°C | 6.3°C | 4.7°C | 12.0°C | 0.4°C | 109 mm | 92% | 4.5 m/s | 0.4 |
| 2001 | 6.5°C | 4.2°C | 1.9°C | 12.4°C | -1.5°C | 30 mm | 92% | 4.4 m/s | 0.7 |
| 2000 | 7.7°C | 6.2°C | 4.8°C | 12.6°C | -1.7°C | 77 mm | 92% | 5.4 m/s | 0.6 |
| 1999 | 6.9°C | 4.9°C | 2.9°C | 11.9°C | -1.3°C | 71 mm | 92% | 5.8 m/s | 0.6 |
| 1998 | 7.5°C | 5.7°C | 3.9°C | 12.3°C | -1.3°C | 79 mm | 94% | 4.9 m/s | 0.5 |
| 1997 | 8.3°C | 6.6°C | 4.9°C | 13.6°C | 0.5°C | 96 mm | 92% | 5.3 m/s | 0.5 |
| 1996 | 5.4°C | 3.6°C | 1.8°C | 11.1°C | -3.2°C | 35 mm | 87% | 4.2 m/s | 0.5 |
| 1995 | 5.2°C | 3.5°C | 1.9°C | 11.5°C | -2.4°C | 78 mm | 89% | 3.9 m/s | 0.5 |
| 1994 | 9.2°C | 7.0°C | 4.9°C | 13.2°C | -0.7°C | 60 mm | 92% | 5.4 m/s | 0.7 |
| 1993 | 7.4°C | 5.3°C | 3.2°C | 13.3°C | -0.1°C | 101 mm | 92% | 5.9 m/s | 0.6 |
| 1992 | 6.8°C | 4.8°C | 2.7°C | 12.6°C | -0.1°C | 49 mm | 91% | 4.4 m/s | 0.6 |
| 1991 | 6.9°C | 5.0°C | 3.0°C | 12.4°C | -2.6°C | 27 mm | 90% | 3.9 m/s | 0.7 |
| 1990 | 6.8°C | 4.7°C | 2.6°C | 11.0°C | -0.4°C | 49 mm | 90% | 5.1 m/s | 0.5 |
| 1989 | 8.2°C | 6.3°C | 4.3°C | 12.9°C | 0.7°C | 92 mm | 92% | 4.2 m/s | 0.6 |
| 1988 | 8.4°C | 6.6°C | 4.8°C | 11.6°C | 1.4°C | 22 mm | 94% | 4.6 m/s | 0.6 |
| 1987 | 7.8°C | 6.2°C | 4.5°C | 12.8°C | -0.4°C | 28 mm | 92% | 4.5 m/s | 0.5 |
| 1986 | 8.0°C | 5.8°C | 3.7°C | 13.6°C | 0.3°C | 70 mm | 92% | 6.1 m/s | 0.6 |
| 1985 | 8.4°C | 6.7°C | 5.0°C | 12.3°C | -2.8°C | 87 mm | 92% | 5.1 m/s | 0.6 |
| 1984 | 7.9°C | 5.9°C | 4.0°C | 12.2°C | 0.8°C | 63 mm | 93% | 4 m/s | 0.7 |
| 1983 | 7.3°C | 5.6°C | 3.8°C | 11.9°C | -1.4°C | 63 mm | 92% | 5.1 m/s | — |
| 1982 | 6.7°C | 4.5°C | 2.4°C | 11.6°C | -1.7°C | 60 mm | 91% | 4.8 m/s | — |
| 1981 | 3.5°C | 1.7°C | -0.2°C | 8.8°C | -4.1°C | 64 mm | 92% | 4.4 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 7.6°C with lows near 3.8°C (mean 5.7°C), based on 45 years of NASA POWER data.
December averages 68 mm of rainfall in Harwich, a relatively wet time of year. The wettest on record was 131 mm in 2020.
The hottest December reached 13.6°C in 1986. The coldest dipped to -4.1°C in 1981.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.9°C. Daytime highs moved from 6.8°C to 8.6°C and overnight lows from 3°C to 5°C over the same span.
December is one of the cooler months of the year in Harwich and a relatively wet time of year, so plan for around 7.6°C daytime highs and 3.8°C at night.
Not quite — December is the 3rd coolest month in Harwich, averaging 5.7°C.
For December in Harwich, pack warm layers and a jacket for chilly mornings, with typical highs of 7.6°C and lows of 3.8°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 92% — quite humid.
Average wind speed in December is 4.8 m/s. The windiest December on record averaged 6.2 m/s (2015).
The wettest December on record was 2020 with 131 mm. On average, December sees 68 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 Harwich 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.
