December Weather in Carmarthen, United Kingdom

Last updated: March 17, 2025

December in Carmarthen, United Kingdom, presents a quintessential winter experience characterized by a maximum temperature of 13°C (55°F) and an average of 8°C (46°F). The chill sets in with minimum temperatures dropping to 0°C (32°F), creating a brisk atmosphere. Rainfall is a frequent visitor, with 184 mm (7.2 in) of precipitation spread over 20 days, making it one of the wetter months. The high humidity level of 89% adds to the cold, enveloping the town in a damp, chilly embrace. Whether you're strolling through the historic streets or enjoying the festive spirit, December's weather in Carmarthen is both invigorating and atmospheric.

December Temperature in Carmarthen

In Carmarthen, December ushers in the colder season with temperatures that reflect a transition into winter. The month typically sees minimum temperatures around 0°C (32°F), while average highs peak at a modest 13°C (55°F). This steady decline from the milder autumn months marks an arrival of chillier days, with the average temperature resting at 8°C (46°F). As the year concludes, residents can expect a mix of cooler evenings and brisk, frosty mornings, setting the scene for the festive season. Compared to November, where temperatures hover slightly higher, December brings a sharper bite, hinting at the deeper winter months ahead. Carmarthen's climatic shifts provide a vivid reminder of the seasonal transition, as the warmth of autumn gives way to the crispness of winter.

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

The chart illustrates December temperature patterns in Carmarthen, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec434445485359626158544846
Data source: Temperature data for Carmarthen generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Carmarthen

December in Carmarthen, United Kingdom, marks a notable peak in precipitation, with 184 mm (7.2 in) of rainfall spread across 20 days. This significant amount not only highlights December as the wettest month of the year but also reflects a trend of increasing rain as the season progresses. Following a steady rise from 151 mm in November, the spike in December underscores the typical winter pattern in this region, where days become shorter and wetter. The 20 days of rain further illustrate a shift towards more persistent weather, contrasting with the relatively drier spring months. As the year wraps up, Carmarthen's landscape transforms into a lush, water-rich environment, setting the stage for the wetter conditions of early winter.

December Precipitation Trends in Carmarthen

The chart displays monthly precipitation patterns in Carmarthen, 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.
JanFebMarAprMayJunJulAugSepOctNovDec99136115619010091134115171151184
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Carmarthen

In Carmarthen, United Kingdom, December marks a return to higher humidity levels, with figures soaring to 89%, similar to those seen in October. The month follows a steadily rising trend that begins in the cooler autumn months, where humidity peaked at 90% in November. As winter sets in, the general pattern shows a gradual decrease from the 80% range in late spring and summer to the cozy dampness characteristic of the cooler months, reflecting the seasonal shift. Despite the chill in the air, December's humidity maintains a lush environment, echoing the town's rich greenery.

December Average Humidity in Carmarthen

This chart illustrates the average monthly humidity levels in Carmarthen, 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 Carmarthen

In December, Carmarthen experiences a low UV Index of 1, reflecting the typical winter season when sun exposure is minimal, and the risk of sunburn is negligible. With a burn time of 45 minutes, residents and visitors can comfortably enjoy outdoor activities without fear of overexposure. This trend of low UV levels carries over from November, where the index also remained at 2, indicative of a gradual decline in UV radiation as winter sets in. As we look back at the year, the UV Index in Carmarthen illustrates a clear pattern: values peak during the summer months of June and July, reaching a very high level of 8, before tapering off as the colder months approach. For more details on UV levels throughout the year, visit Carmarthen UV Index.

Maximum UV Index Levels in Carmarthen for December

The chart shows the monthly maximum UV Index (UVI) for Carmarthen 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: Carmarthen 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 Carmarthen

In Carmarthen, December ushers in a brief respite from the longer days of summer, with a gentle decline in sunshine hours to 114. This is a significant decrease from the summer peak of 422 hours in July, as the year transitions into winter's embrace. Interestingly, as we move through the colder months, sunshine hours gradually drop after October's 245, highlighting a trend where the city feels the absence of light. However, December's 114 hours still provide a modest glow, laying the groundwork for the promise of longer days as the new year approaches. The crisp air and soft winter light create a unique charm, enticing residents and visitors alike to embrace the serene beauty of this season in Carmarthen.

Monthly Sunshine Duration in Carmarthen: December Highlighted

The December sunshine duration represents the total number of hours Carmarthen 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.
JanFebMarAprMayJunJulAugSepOctNovDec97h157h229h341h409h401h422h379h313h245h138h114h
Data source: Carmarthen December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Carmarthen During December

In Carmarthen, December brings a modest 22% chance of sunshine, marking it as one of the more overcast months of the year. This figure reflects a slight decline from the more vibrant spring and early summer months, such as April's peak of 53%. While the chance of sun in December is higher than in October (20%) and closely mirrors November's 25%, it underscores the seasonal transition as the year draws to a close. As the cold sets in, residents can expect a mix of cloudy skies and occasional glimpses of sunlight, reminding them that even in winter, nature has its moments of brightness.

Percentage of Sunny Days in December in Carmarthen

The chart illustrates the percentage of sunny days in Carmarthen 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 Carmarthen experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec26%24%29%54%32%26%40%34%27%20%25%22%
Data source: Carmarthen December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Carmarthen in December

As December arrives in Carmarthen, the daylight hours peak at a modest 7 hours, marking the year's shortest days. This decline from the brighter summer months—where daylight stretched to a generous 16 hours in both June and July—reflects the natural rhythm of the seasons. From the lengthening days of spring and summer, peaking in warmth and light, the transition into winter is marked by a gradual decrease, dropping to 8 hours in both January and November, before hitting the winter solstice. As the year progresses, these trends underscore the cyclical nature of daylight, reminding residents of the cozy charm of the shorter, darker days of December, perfect for celebrating the festive season.

Average Daylight Hours in Carmarthen for December

The chart illustrates the variation in daylight duration in Carmarthen throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 21m9h 57m11h 55m13h 55m15h 41m16h 36m16h 6m14h 31m12h 35m10h 35m8h 47m7h 50m
Data source: Carmarthen daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Carmarthen

As December unfolds in Carmarthen, the wind's presence becomes notably more pronounced, with an average speed of 6.2 m/s (14 mph), signaling a brisk end to the year. This increase adds a touch of vitality to the winter landscape, contrasting with the calmer breezes of summer months, which hover below 4.5 m/s (10 mph). The winds begin to pick up in autumn, with October recording an average of 5.9 m/s (13 mph), paving the way for December's gusty conditions. As we transition from a relatively tranquil summer into the lively winds of late autumn and winter, December’s breezes remind us of nature's dynamic rhythm in this charming Welsh town.

Average December Wind Speed in Carmarthen

The chart displays monthly wind speed patterns in Carmarthen, 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.46.55.53.95.13.83.54.53.95.94.86.2 m/s
Data source: Carmarthen December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Carmarthen Compares to Other Months

The weather in Carmarthen 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 Carmarthen and find detailed weather information for every month.

In December, the weather features a milder average temperature of 8°C (46°F), with a minimum of 0°C (32°F) and a maximum reaching 13°C (55°F). However, it also sees significant precipitation, totaling 184 mm (7.2 in) over 20 days, resulting in high humidity at 89%. In contrast, January experiences cooler temperatures, with an average of 6°C (43°F), dipping to a minimum of -2°C (28°F) and still peaking at 13°C (56°F). Precipitation decreases notably to 99 mm (3.9 in) over 13 days, maintaining a slightly lower humidity of 88%. For more specific details on January weather in Carmarthen, you can visit Carmarthen weather in January.

December and February exhibit notable differences in their weather patterns. In December, temperatures range from a chilly minimum of 0°C (32°F) to a maximum of 13°C (55°F), with an average of 8°C (46°F). This month experiences significant precipitation, totaling 184 mm (7.2 in) over 20 days, contributing to high humidity at 89%.

In contrast, February sees slightly colder temperatures, with a minimum of -2°C (28°F) and an average of 7°C (44°F), reaching a maximum of 14°C (58°F). The precipitation is lower at 136 mm (5.3 in) over 17 days, and humidity remains comparable at 88%. For more detailed insights, you can check Carmarthen weather in February.

December and March present quite different weather conditions. In December, temperatures hover between a minimum of 0°C (32°F) and a maximum of 13°C (55°F), with average precipitation of 184 mm (7.2 in) across about 20 days, resulting in a humid atmosphere with an average humidity of 89%. In contrast, March experiences cooler temperatures, with a minimum of -5°C (24°F) and a maximum of 16°C (61°F), and notably less precipitation at 115 mm (4.5 in) over 18 days, maintaining a slightly lower humidity of 86%. For more detailed insights, you can check out the weather specifics in this link: Carmarthen weather in March.

In December, the weather presents a chillier atmosphere, with average temperatures ranging from 0°C (32°F) at night to a mild 13°C (55°F) during the day. Rainfall is quite significant, with 184 mm (7.2 in) spread over 20 days, contributing to a high humidity level of 89%. In contrast, April ushers in a more temperate climate, featuring higher daytime temperatures that can reach up to 19°C (67°F) while still seeing nighttime lows of 0°C (32°F). Precipitation is less frequent, totaling 61 mm (2.4 in) over just 11 days, and the humidity dips slightly to 84%. For more details on what to expect, check out Carmarthen weather in April.

In December, the weather is notably cooler with temperatures ranging from a minimum of 0°C (32°F) to a maximum of 13°C (55°F), averaging around 8°C (46°F). The month experiences significant precipitation of 184 mm (7.2 in) over approximately 20 days, accompanied by high humidity levels at 89%. In contrast, May brings a more moderate climate, with temperatures ranging from 2°C (36°F) to 23°C (73°F) and an average of 12°C (53°F). Precipitation drops to 90 mm (3.5 in) over about 12 days, and humidity decreases to 80%. This shift indicates a transition from the damp and chilly conditions of December to the milder and drier weather typical of May. For more detailed information, check Carmarthen weather in May.

December and June present stark contrasts in weather, each characterized by distinct conditions. In December, temperatures range from a chilly 0°C (32°F) to a mild 13°C (55°F), with an average of 8°C (46°F). The month sees considerable precipitation, totaling 184 mm (7.2 in) over approximately 20 days, coupled with high humidity at 89%, contributing to a damp and often overcast atmosphere. In contrast, June offers a more vibrant experience, with temperatures ranging from a minimum of 7°C (45°F) to a maximum of 25°C (78°F) and an average of 15°C (59°F). Precipitation is lower, at 100 mm (3.9 in) over about 16 days, and humidity is somewhat reduced at 80%. The overall feel in June is significantly warmer and sunnier, making it a popular month for outdoor activities. For more detailed information, you can check out Carmarthen weather in June.

When comparing the weather in December and July, December is characterized by much colder temperatures, with a minimum of 0°C (32°F) and average highs reaching only 13°C (55°F). The month sees significant precipitation, totaling 184 mm (7.2 in) over about 20 days, and an increased humidity level of 89%. In contrast, July enjoys milder, more pleasant weather, where temperatures range from a minimum of 8°C (48°F) to a maximum of 26°C (79°F). The month typically experiences less rainfall, approximately 91 mm (3.6 in) over 13 days, and a lower humidity of 70%. For more details on July weather, you can visit Carmarthen weather in July.

When comparing the weather in December and August, it's evident that they offer contrasting experiences. December temperatures range from a chilly 0°C (32°F) to a mild 13°C (55°F), with an average of 8°C (46°F) and frequent precipitation of 184 mm (7.2 in) spread across 20 days, contributing to a high humidity of 89%. In contrast, August boasts a more comfortable climate, with temperatures varying from 9°C (49°F) to a warm 25°C (78°F) and an average of 16°C (61°F). Precipitation in August is lower at 134 mm (5.3 in) over 19 days, along with a more moderate humidity level of 73%. For more detailed information about August weather, you can explore Carmarthen weather in August.

In December, the weather is significantly colder than in September, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 13°C (55°F), compared to September's more mild range of 5°C (42°F) to 25°C (78°F). Additionally, December experiences higher precipitation, with 184 mm (7.2 in) over 20 days, while September sees a more moderate 115 mm (4.5 in) across 16 days. The humidity also increases in December, reaching 89%, compared to September's 79%. For more detailed information on September weather, check out Carmarthen weather in September.

In comparing the weather between December and October, we observe notable differences in temperature and precipitation patterns. October experiences milder conditions, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 20°C (68°F). In contrast, December tends to be cooler, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 13°C (55°F). Though both months have high humidity levels at 89%, December sees an increase in precipitation, totaling 184 mm (7.2 in) over 20 days, compared to October's 171 mm (6.7 in) over 18 days. For more details, check out Carmarthen weather in October.

When comparing the weather in December to November, we see that December is slightly cooler, with average temperatures ranging from a minimum of 0°C (32°F) to a maximum of 13°C (55°F), while November has a higher average of 9°C (49°F) and a maximum of 15°C (60°F). Precipitation also increases in December, totaling 184 mm (7.2 in) over 20 days, compared to November's 151 mm (6.0 in) over 18 days. Additionally, humidity remains consistent, with December at 89% and November slightly higher at 90%. For more details on November weather, check out this link: Carmarthen weather in November.

Compare Carmarthen's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Carmarthen

December in Carmarthen brings a noticeable chill, as temperatures dip significantly compared to the milder months before. This month is characterized by frequent rainfall, with over two-thirds of the days seeing precipitation, contributing to a pronounced sense of humidity. The air feels crisper and damper, setting a distinct contrast to the more temperate fall months. As residents embrace the festive season, the cloudy skies and occasional frost add a unique charm to the landscape. For a deeper understanding of what to expect throughout the year, visit Carmarthen Climate.