December is one of the cooler months of the year in Ballymena, with average highs near 7.2°C and lows around 4.3°C (mean 5.8°C). It is a relatively wet time of year, averaging 112 mm of rainfall and 91% relative humidity across the period.
December is one of the cooler months of the year in Ballymena. Across 45 years of records, the warmest December in Ballymena was 2015 — when the month averaged 7.6°C — while the coldest was 2010 at 2.5°C. Typical December days reach 7.2°C with nights near 4.3°C. The long-term trend is warming, about 0.3°C per decade.
December is a relatively wet time of year in Ballymena, averaging 112 mm of rainfall. The wettest December on record was 1999 with 193 mm, while the driest was 2010 at 53 mm.
Relative humidity in Ballymena during December averages 91%. The most humid December was 2018 at 93%, and the least humid was 1995 at 88%.
December receives about 0.4 kWh/m²/day of solar energy in Ballymena. The sunniest Decembers were 2019, 2020 and 2022, among others at 0.5 kWh/m²/day, and the cloudiest were 2021, 2023 and 2024, among others at 0.4.
Average wind speed in Ballymena during December is 5.6 m/s. The windiest December was 2013 at 7.3 m/s, while the calmest was 2010 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 | 5.3°C | 5.9°C | 5.9°C | 6.4°C | +0.9°C |
| Avg High | 7.0°C | 6.8°C | 7.4°C | 7.4°C | 7.8°C | +0.8°C |
| Avg Low | 4.1°C | 3.8°C | 4.4°C | 4.3°C | 5.0°C | +0.9°C |
| Avg Rain | 103 mm | 114 mm | 106 mm | 117 mm | 123 mm | +20 mm |
December temperatures in Ballymena have risen by about 1.4°C between 1981–1985 and 2021–2025.
December has ranged from a record low of -3.7°C (1981) to a record high of 13.3°C (2016).
Rainfall in December is a relatively wet time of year, averaging 112 mm, with a wettest year of 193 mm.
A quieter season to visit Ballymena
If your dates are flexible, the more temperate months of July and August tend to be the most comfortable for visiting Ballymena. That said, December — with days averaging 7.2°C and nights around 4.3°C (mean 5.8°C) and higher rainfall (112 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 | 8.1°C | 6.7°C | 5.2°C | 13.1°C | 2.3°C | 115 mm | 93% | 5.3 m/s | — |
| 2024 | 9.0°C | 7.3°C | 5.7°C | 12.0°C | 2.7°C | 105 mm | 90% | 6 m/s | 0.4 |
| 2023 | 8.4°C | 7.1°C | 5.9°C | 11.7°C | 1.8°C | 161 mm | 91% | 6.2 m/s | 0.4 |
| 2022 | 6.3°C | 4.9°C | 3.5°C | 12.4°C | 0.6°C | 101 mm | 91% | 4.9 m/s | 0.5 |
| 2021 | 8.1°C | 6.7°C | 5.2°C | 11.6°C | 2.8°C | 139 mm | 92% | 5.2 m/s | 0.4 |
| 2020 | 7.1°C | 5.9°C | 4.6°C | 10.8°C | 2.1°C | 118 mm | 90% | 5.6 m/s | 0.5 |
| 2019 | 7.6°C | 6.1°C | 4.6°C | 11.7°C | 1.5°C | 117 mm | 93% | 5.8 m/s | 0.5 |
| 2018 | 8.4°C | 7.0°C | 5.6°C | 11.1°C | 2.5°C | 112 mm | 93% | 5.5 m/s | 0.4 |
| 2017 | 7.2°C | 5.7°C | 4.2°C | 12.1°C | 0.2°C | 109 mm | 91% | 5.3 m/s | 0.4 |
| 2016 | 8.3°C | 6.8°C | 5.2°C | 13.3°C | 2.2°C | 79 mm | 93% | 5.5 m/s | 0.5 |
| 2015 🔥 | 9.7°C | 7.6°C | 5.5°C | 12.9°C | 1.7°C | 171 mm | 91% | 7 m/s | 0.4 |
| 2014 | 7.0°C | 5.6°C | 4.2°C | 11.3°C | 0.9°C | 123 mm | 90% | 6 m/s | 0.5 |
| 2013 | 8.0°C | 6.3°C | 4.6°C | 12.3°C | 1.7°C | 102 mm | 92% | 7.3 m/s | 0.4 |
| 2012 | 6.8°C | 5.3°C | 3.8°C | 11.2°C | 1.9°C | 156 mm | 91% | 5.4 m/s | 0.5 |
| 2011 | 7.3°C | 5.8°C | 4.3°C | 11.5°C | 1.2°C | 149 mm | 90% | 7.2 m/s | 0.4 |
| 2010 ❄️ | 3.9°C | 2.5°C | 1.1°C | 8.3°C | -2.4°C | 53 mm | 89% | 3.7 m/s | 0.5 |
| 2009 | 5.7°C | 4.4°C | 3.0°C | 10.1°C | 0.5°C | 82 mm | 90% | 4.6 m/s | 0.5 |
| 2008 | 6.6°C | 5.0°C | 3.4°C | 10.8°C | 0.8°C | 84 mm | 90% | 4.7 m/s | 0.5 |
| 2007 | 8.1°C | 6.4°C | 4.6°C | 12.7°C | 2.1°C | 109 mm | 91% | 6 m/s | 0.4 |
| 2006 | 8.3°C | 6.8°C | 5.2°C | 11.8°C | 2.0°C | 134 mm | 92% | 6.3 m/s | 0.4 |
| 2005 | 7.9°C | 6.5°C | 5.1°C | 10.9°C | 1.3°C | 106 mm | 91% | 4.8 m/s | 0.4 |
| 2004 | 8.2°C | 6.6°C | 5.1°C | 11.0°C | 1.1°C | 102 mm | 91% | 6.2 m/s | 0.4 |
| 2003 | 7.8°C | 6.3°C | 4.7°C | 11.0°C | 1.0°C | 112 mm | 90% | 5.2 m/s | 0.4 |
| 2002 | 6.9°C | 6.0°C | 5.0°C | 11.1°C | 2.2°C | 86 mm | 90% | 5.1 m/s | 0.4 |
| 2001 | 7.1°C | 5.4°C | 3.8°C | 11.0°C | 0.5°C | 84 mm | 90% | 5.2 m/s | 0.5 |
| 2000 | 7.0°C | 5.7°C | 4.5°C | 11.2°C | -0.9°C | 166 mm | 92% | 5.6 m/s | 0.4 |
| 1999 🌧️ | 6.9°C | 5.3°C | 3.7°C | 11.2°C | 0.6°C | 193 mm | 89% | 6.5 m/s | 0.4 |
| 1998 | 8.1°C | 6.2°C | 4.3°C | 12.0°C | 0.9°C | 105 mm | 91% | 6.1 m/s | 0.4 |
| 1997 | 7.8°C | 6.6°C | 5.3°C | 11.6°C | 1.9°C | 134 mm | 92% | 5.9 m/s | 0.4 |
| 1996 | 5.5°C | 4.3°C | 3.0°C | 9.4°C | 0.6°C | 66 mm | 90% | 4.9 m/s | 0.5 |
| 1995 | 5.3°C | 4.0°C | 2.7°C | 11.8°C | -1.8°C | 56 mm | 88% | 4.8 m/s | 0.4 |
| 1994 | 7.9°C | 6.3°C | 4.7°C | 13.0°C | 1.8°C | 136 mm | 90% | 6.6 m/s | 0.4 |
| 1993 | 6.5°C | 4.9°C | 3.3°C | 10.9°C | 0.6°C | 175 mm | 90% | 6.5 m/s | 0.4 |
| 1992 | 6.1°C | 4.7°C | 3.2°C | 9.3°C | 0.6°C | 96 mm | 92% | 5.1 m/s | 0.5 |
| 1991 | 7.7°C | 6.2°C | 4.7°C | 11.5°C | 1.1°C | 76 mm | 91% | 5.4 m/s | 0.5 |
| 1990 | 6.3°C | 4.6°C | 2.9°C | 10.8°C | 0.6°C | 102 mm | 89% | 5.8 m/s | 0.4 |
| 1989 | 6.4°C | 5.0°C | 3.6°C | 10.6°C | 1.7°C | 75 mm | 89% | 4.7 m/s | 0.5 |
| 1988 | 8.9°C | 7.4°C | 6.0°C | 11.4°C | 2.5°C | 73 mm | 92% | 6.2 m/s | 0.4 |
| 1987 | 7.6°C | 6.3°C | 5.0°C | 11.6°C | 1.4°C | 75 mm | 90% | 5.3 m/s | 0.4 |
| 1986 | 7.3°C | 5.5°C | 3.6°C | 11.3°C | 1.0°C | 170 mm | 90% | 6.5 m/s | 0.4 |
| 1985 | 7.3°C | 6.0°C | 4.6°C | 12.5°C | -1.0°C | 96 mm | 91% | 5.5 m/s | 0.4 |
| 1984 | 7.1°C | 5.6°C | 4.2°C | 10.7°C | -0.2°C | 110 mm | 92% | 5.4 m/s | 0.4 |
| 1983 | 8.0°C | 6.5°C | 5.0°C | 11.0°C | 2.5°C | 123 mm | 91% | 6.2 m/s | — |
| 1982 | 6.2°C | 4.7°C | 3.1°C | 10.9°C | 1.0°C | 140 mm | 90% | 6 m/s | — |
| 1981 | 4.1°C | 2.8°C | 1.4°C | 10.5°C | -3.7°C | 69 mm | 88% | 4.9 m/s | — |
Actual recorded December data for each year, 1981–2025 — sourced from NASA POWER.
The average high in December is around 7.2°C with lows near 4.3°C (mean 5.8°C), based on 45 years of NASA POWER data.
December averages 112 mm of rainfall in Ballymena, a relatively wet time of year. The wettest on record was 193 mm in 1999.
The hottest December reached 13.3°C in 2016. The coldest dipped to -3.7°C in 1981.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average December temperatures have risen by about 1.4°C. Daytime highs moved from 6.5°C to 8°C and overnight lows from 3.7°C to 5.1°C over the same span.
December is one of the cooler months of the year in Ballymena and a relatively wet time of year, so plan for around 7.2°C daytime highs and 4.3°C at night.
Not quite — December is the 3rd coolest month in Ballymena, averaging 5.8°C.
For December in Ballymena, pack warm layers and a jacket for chilly mornings, with typical highs of 7.2°C and lows of 4.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in December averages 91% — quite humid.
Average wind speed in December is 5.6 m/s. The windiest December on record averaged 7.3 m/s (2013).
The wettest December on record was 1999 with 193 mm. On average, December sees 112 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 Ballymena 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.
