December Weather in Swansea, United Kingdom

Last updated: March 17, 2025

In December, Swansea experiences a typical winter climate characterized by mild temperatures and significant precipitation. With a maximum of 13°C (55°F) and an average of 8°C (47°F), daily highs often give way to cooler minimum temperatures of 2°C (35°F) at night. This month is notably wet, receiving an average of 184 mm (7.3 in) of rain over 21 days, resulting in a high humidity level of 89%. Residents and visitors should prepare for a mix of damp and chilly conditions, making cozy indoor activities a perfect complement to the season's festive spirit.

December Temperature in Swansea

As December rolls into Swansea, the temperatures begin to dip, marking a transition into the heart of winter. With a minimum of 2°C (35°F), nights become noticeably cooler, while the average temperature settles at 8°C (47°F). This trend reflects a slight decline from the milder conditions of autumn, where November enjoyed an average of 10°C (50°F). Throughout the month, daytime temperatures reach a maximum of 13°C (55°F), providing a cool yet manageable atmosphere perfect for festive activities. Overall, December's chill embraces the city with the promise of seasonal charm, making it a cozy time to explore Swansea's winter delights.

December Weather in Swansea: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Swansea, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec444546495359626259555047
Data source: Temperature data for Swansea generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Swansea

December in Swansea typically sees a substantial increase in precipitation, with an average of 184 mm (7.3 in), matching the wettest month of October. This month also stands out for its 21 rainy days, marking it as one of the dampest times of the year. The trend reflects a pattern of increased rainfall during the winter months, as November and October also register high precipitation levels. Collectively, these figures illustrate Swansea's characteristic maritime climate, where rain is a frequent visitor, particularly as the year draws to a close, making December a month where residents often prepare for a cozy, wet winter.

December Precipitation Trends in Swansea

The chart displays monthly precipitation patterns in Swansea, with values for each month alongside December's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec10612811456809391123120184143184
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Swansea

In December, Swansea experiences a notable increase in humidity, with levels reaching 89%, aligning closely with the higher readings seen in the preceding months of October and November. This trend reflects a distinct winter pattern, where the year culminates in elevated moisture levels, contrasting sharply with the drier summer months—particularly July and August, which dip to 70% and 73%, respectively. The consistent humidity throughout late autumn and into the winter serves as a reminder of the region's maritime climate, ensuring that residents and visitors alike should brace for the dampness that accompanies the season's chill. As the year winds down, December's humidity helps create an atmospheric backdrop that is both invitingly crisp yet undeniably humid, setting the stage for a classically dreary British winter.

December Average Humidity in Swansea

This chart illustrates the average monthly humidity levels in Swansea, with December's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how December's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec89%88%86%84%80%80%70%73%79%89%90%89%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Swansea

In December, Swansea sees a low UV Index of 1, indicating minimal sun exposure risk, with a burn time of approximately 45 minutes. This marks a continuation of a trend as the year winds down; following the moderate to high indices of summer and early autumn months, December brings a welcome return to lower levels. It reflects a seasonal shift where families can enjoy outdoor activities with less concern for sunburn. As daylight hours decrease and temperatures cool, it's a good time to appreciate the outdoor beauty of Swansea without the intense UV rays. For more details, check out the full report on the Swansea UV Index.

Maximum UV Index Levels in Swansea for December

The chart shows the monthly maximum UV Index (UVI) for Swansea in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec124678876421
Data source: Swansea December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Swansea

In Swansea during December, the sun graces the skies for about 110 hours, marking a notable dip as we transition into winter. This decline is part of a consistent trend seen throughout the colder months, where sunlight hours typically fall from the vibrant highs of summer. For instance, after basking in a sunlit 418 hours in July, December’s light feels quite modest in comparison. This gradual decrease underscores the shift from the lush brightness of spring and summer—404 hours in May to just 93 hours in January—highlighting the seasonal ebb and flow of light that characterizes this beautiful coastal city. As the year closes, those limited December rays beckon for cozy days indoors, anticipating the return of longer, sun-filled days in the New Year.

Monthly Sunshine Duration in Swansea: December Highlighted

The December sunshine duration represents the total number of hours Swansea experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec93h151h219h333h404h391h418h374h309h241h135h110h
Data source: Swansea December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Swansea During December

As December rolls into Swansea, the prospect of sunny weather takes a dip, with only a 21% chance of sunshine gracing the skies. This marks one of the lowest probabilities in the yearly cycle, following a slight uptick in sun exposure from April’s 56% peak. The colder months, particularly November and October, also reflect reduced sunlight, hovering around 27% and 22% respectively. Overall, the trend indicates that while the warm months offer more opportunities for radiant days, winter firmly settles into a gloomier ambiance, making the rare sunny moments in December all the more special.

Percentage of Sunny Days in December in Swansea

The chart illustrates the percentage of sunny days in Swansea throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Swansea experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec24%25%31%56%35%27%42%35%29%22%27%22%
Data source: Swansea December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Swansea in December

In Swansea, United Kingdom, December brings a dip in daylight, offering only 7 hours of sunlight, the shortest of the year. This decline follows a steady increase from the darker months of November, which also has 8 hours of daylight, making the transition into winter quite pronounced. The trend is clear throughout the year, as daylight peaks in the summer with up to 16 hours in June and July, only to descend back to the darker months of winter. As the days grow shorter, the rich beauty of Swansea’s winter landscapes comes into focus, inviting residents and visitors alike to embrace the charm of the season, even as daylight diminishes.

Average Daylight Hours in Swansea for December

The chart illustrates the variation in daylight duration in Swansea throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 23m9h 58m11h 55m13h 54m15h 38m16h 32m16h 3m14h 30m12h 35m10h 36m8h 50m7h 53m
Data source: Swansea daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Swansea

As December rolls into Swansea, residents can expect a brisk average wind speed of 7.3 m/s (16 mph), making it one of the windiest months of the year. This uptick in wind strength follows a notable trend observed throughout the winter months, with January and February also showcasing higher speeds compared to the spring and summer. Interestingly, while April through July brings a gentle breeze with average speeds dropping to around 4.1 - 5.8 m/s, the autumn months see a resurgence, particularly in October and November, where winds pick up again. This pattern suggests that Swansea's coastal climate embraces a dynamic transition from calm to gusty conditions as the year closes, resonating with the vibrant energy of the season.

Average December Wind Speed in Swansea

The chart displays monthly wind speed patterns in Swansea, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec6.57.46.24.75.84.14.15.24.76.65.77.3 m/s
Data source: Swansea December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Swansea Compares to Other Months

The weather in Swansea changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Swansea and find detailed weather information for every month.

December and January present somewhat similar weather patterns but with notable differences. In December, temperatures range from a chilly 2°C (35°F) to a mild 13°C (55°F), averaging around 8°C (47°F). This month is characterized by significant precipitation, totaling 184 mm (7.3 in) over 21 days, and a high humidity level of 89%. In contrast, January sees slightly cooler temperatures, with a minimum of 0°C (32°F) and a maximum of 14°C (57°F), averaging 7°C (45°F). Precipitation drops to 106 mm (4.2 in) over 14 days, while humidity remains fairly consistent at 88%. For those curious about the specifics of weather during this time, you can find more details here: Swansea weather in January.

In December, temperatures in Swansea typically range from a minimum of 2°C (35°F) to a maximum of 13°C (55°F), with an average temperature of 8°C (47°F). This month experiences significant precipitation, with about 184 mm (7.3 in) falling over 21 days, and humidity levels remain high at 89%. In contrast, February sees slightly cooler conditions, with minimum temperatures dipping to -1°C (30°F), while still reaching up to 13°C (55°F) on the warmer days. The average temperature in February is 7°C (45°F), and it has less precipitation overall at 128 mm (5.0 in) over 17 days, with humidity slightly lower at 88%. For more detailed information, you can check this link: Swansea weather in February.

December weather is typically cooler, with average temperatures ranging from 2°C (35°F) at night to a maximum of 13°C (55°F) during the day, coupled with high humidity levels at 89%. In contrast, March sees the minimum temperature drop further to -4°C (25°F) while maintaining a similar average of 8°C (46°F) and reaching up to 15°C (59°F) at its warmest. Additionally, March experiences less rainfall, with 114 mm (4.5 in) over 18 days compared to December's 184 mm (7.3 in) over 21 days, and slightly lower humidity at 86%. For more details on March weather specifics, you can check Swansea weather in March.

In December, the weather tends to be considerably colder and wetter, with average temperatures ranging from 2°C to 13°C (35°F to 55°F) and an impressive 184 mm (7.3 in) of precipitation spread over 21 days, contributing to a high humidity level of 89%. In contrast, April presents a more moderate climate, featuring slightly higher temperatures that range from 2°C to 17°C (36°F to 63°F) and significantly less rainfall, totaling only 56 mm (2.2 in) over about 9 days, along with lower humidity at 84%. For a detailed look at the month of April in Swansea, you can check out Swansea weather in April.

In December, the weather is quite chilly, with average temperatures ranging from 2°C (35°F) to a maximum of 13°C (55°F). This month experiences significant precipitation, totaling 184 mm (7.3 in) over 21 days, and the humidity remains high at 89%. In contrast, May brings a more pleasant climate, with temperatures varying from a minimum of 5°C (40°F) to a maximum of 21°C (70°F). The precipitation in May is also much lower, averaging 79 mm (3.1 in) over just 11 days, and humidity decreases to 80%. For more details on May weather specifics, visit Swansea weather in May.

December and June present a striking contrast in weather patterns. In December, temperatures range from a chilly 2°C (35°F) to a mild 13°C (55°F), characterized by high humidity levels at 89% and significant precipitation of 184 mm (7.3 in) over 21 days. In stark contrast, June offers more pleasant conditions, with temperatures varying between a minimum of 9°C (48°F) and a comfortable maximum of 24°C (76°F). Precipitation is notably lower at 93 mm (3.6 in) spread over 15 days, and humidity decreases to a more tolerable 80%. For a deeper dive into the weather specifics in June, you can check out Swansea weather in June.

December weather in Swansea is significantly cooler and wetter compared to July. During December, the temperatures range from a chilly minimum of 2°C (35°F) to a maximum of 13°C (55°F), with an average of 8°C (47°F). The month sees substantial rainfall, with 184 mm (7.3 in) over 21 rainy days and high humidity at 89%. In contrast, July offers a mild and pleasant climate, with temperatures ranging from a minimum of 11°C (52°F) to a maximum of 24°C (76°F), averaging 17°C (62°F). Rainfall is much lower in July, at 91 mm (3.6 in) over just 13 days, and humidity is also more comfortable at 70%. For a closer look at the conditions, check out Swansea weather in July.

December and August present stark contrasts in weather conditions. December typically features cooler temperatures, with a minimum of 2°C (35°F) and an average of 8°C (47°F), while August enjoys milder weather, showcasing a minimum of 12°C (53°F) and an average of 17°C (62°F). Precipitation levels also differ, with December receiving 184 mm (7.3 in) over 21 days, compared to August's 123 mm (4.8 in) spread across 18 days. Additionally, December's humidity is considerably higher at 89%, while August's is a more manageable 73%. For more detailed insights, check out Swansea weather in August.

December and September present distinctly different weather patterns. In December, temperatures range from a chilly 2°C (35°F) at night to a maximum of 13°C (55°F) during the day, with an average temperature of 8°C (47°F). The month is marked by high humidity levels at 89% and considerable rainfall, totaling 184 mm (7.3 in) over 21 days. In contrast, September enjoys milder conditions, with temperatures fluctuating between a minimum of 9°C (48°F) and a pleasant maximum of 24°C (76°F), averaging around 15°C (60°F). Rainfall is less frequent in September, with 120 mm (4.7 in) across 15 days and a more comfortable humidity level of 79%. For further details on September weather, you can visit Swansea weather in September.

When comparing the weather in December and October, notable differences emerge. December's average temperature is cooler, ranging from a minimum of 2°C (35°F) to a maximum of 13°C (55°F), while October enjoys milder conditions with temperatures peaking at 20°C (68°F). Both months experience similar precipitation levels, totaling around 184 mm (7.2-7.3 in), but December sees slightly more rainy days (21) compared to October's 19 days. Humidity levels remain consistent at 89% in both months. For a closer look at October's weather specifics, you can visit Swansea weather in October.

In comparing the weather between December and November, December tends to be slightly cooler with an average temperature of 8°C (47°F), compared to November's average of 10°C (50°F). While both months experience similar minimum temperatures of 2°C (35°F), December’s maximum temperature is lower at 13°C (55°F) compared to November's 16°C (60°F). Additionally, December sees increased precipitation with 184 mm (7.3 in) over 21 days, whereas November has 143 mm (5.6 in) across 19 days. Humidity levels remain fairly high in both months, with December at 89% and November slightly higher at 90%. For more detailed insights, you can check Swansea weather in November.

Compare Swansea's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Swansea

As December rolls into Swansea, the weather becomes markedly cooler and wetter than in other months. With an average temperature hovering around 8°C (47°F), the chill is felt more keenly as highs of 13°C (55°F) are countered by lows dipping to 2°C (35°F). This month is characterized by frequent rainfall, with approximately 21 days receiving precipitation—contributing to a significant total of 184 mm (7.3 in). The high humidity level of 89% adds to the dampness in the air, making December a stark contrast to the milder, drier months preceding it. For a deeper dive into Swansea's weather patterns throughout the year, explore Swansea Climate.