December Weather in Caernarfon, United Kingdom

Last updated: March 17, 2025

December weather in Caernarfon, United Kingdom is characterized by cool temperatures and considerable rainfall. With a maximum of 13°C (56°F) and an average of 7°C (45°F), the chilly air can dip to a minimum of -1°C (30°F). This month is notably wet, with precipitation totaling 129 mm (5.1 in) over 20 days, contributing to an overall humidity level of 89%. Visitors should prepare for damp conditions while enjoying the festive atmosphere of this historic coastal town.

December Temperature in Caernarfon

In December, Caernarfon experiences a noticeable chill as winter settles in, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F). The average temperature hovers around 7°C (45°F), reflecting a slight dip compared to the milder autumn months. As the year draws to a close, it's clear that the region is transitioning into the colder season, with a trend of decreasing max temperatures that began in November. While brisk, December's climate remains relatively mild compared to the harsh depths of winter, making it a time to enjoy the seasonal charm of the town without the extreme chill seen in January or February.

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

The chart illustrates December temperature patterns in Caernarfon, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec434445485358616057524745
Data source: Temperature data for Caernarfon 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 Caernarfon

December in Caernarfon is typically a wet month, marking the climax of the year’s precipitation patterns. With an average of 129 mm (5.1 in) of rain spread over 20 days, it stands out as one of the wettest months, closely following the heavier rains of October and November. The trend of increasing rainfall is evident as the winter months approach, with December's precipitation often surpassing that of all previous months, emphasizing the shifting weather patterns typical of this coastal region. This consistent rainfall not only fills the rivers and streams but also sets a rather moody and atmospheric backdrop for the festive season, often enveloped in mists and drizzles.

December Precipitation Trends in Caernarfon

The chart displays monthly precipitation patterns in Caernarfon, 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.
JanFebMarAprMayJunJulAugSepOctNovDec771031045571918210598128111129
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Caernarfon

In December, Caernarfon experiences a humidity level of 89%, echoing the trends of earlier winter months. While there is a slight reprieve from the peak of 91% seen in November, the humidity remains notably high, consistent with the region's typical winter climate. This period is characterized by rich, damp air, setting the stage for lush landscapes and a tranquil atmosphere. Interestingly, the months leading up to this point show a gradual decline from the summer lows of 78% in July, highlighting a seasonal pattern where humidity rises as temperatures drop. Overall, December’s humidity reflects the transition into the colder months, maintaining a lush, inviting environment that heralds the depth of winter in this picturesque Welsh town.

December Average Humidity in Caernarfon

This chart illustrates the average monthly humidity levels in Caernarfon, 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%85%79%81%78%79%85%90%91%89%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Caernarfon

As December rolls into Caernarfon, the UV Index dips back down to 1, indicating a low exposure category, much like the preceding months of January and November. This trend reflects the region's colder climate during winter when the sun's rays pose minimal risk for skin damage. With a burn time of 45 minutes, residents and visitors can enjoy outdoor activities with little concern for UV exposure. This seasonal pattern highlights the significant increase in UV levels during the summer months, where the index can reach up to 8 in June and July, demanding more caution. For more detailed insights on UV levels throughout the year, check out Caernarfon UV Index.

Maximum UV Index Levels in Caernarfon for December

The chart shows the monthly maximum UV Index (UVI) for Caernarfon 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.
JanFebMarAprMayJunJulAugSepOctNovDec124578875421
Data source: Caernarfon 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 Caernarfon

As the year winds down, December in Caernarfon, United Kingdom, offers a softer glow with 109 hours of sunshine, a drop that follows the trend of diminishing daylight as winter approaches. This decrease is stark compared to the 421 hours enjoyed in the height of summer, reflecting the seasonal ebb and flow of light. Notably, December ranks among the lower months for sunshine, similar to the gloomy stretch of November, which captures just 126 hours. The transition from the vibrant late spring and summer months illustrates the rhythm of nature, where sunlight wanes significantly from the peak of 415 hours in May to the twilight of the year. While the chilly air may discourage outdoor activities, the modest December sunshine still provides a cozy charm to the picturesque landscape of Caernarfon, inviting residents and visitors alike to appreciate the serenity of winter.

Monthly Sunshine Duration in Caernarfon: December Highlighted

The December sunshine duration represents the total number of hours Caernarfon 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.
JanFebMarAprMayJunJulAugSepOctNovDec93h162h228h335h415h404h421h383h315h238h126h109h
Data source: Caernarfon December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Caernarfon During December

In December, Caernarfon experiences a 23% chance of sunny weather, which is slightly above the colder months of November and October but lower than the more temperate spring months. Throughout the year, the trend reveals that the likelihood of sunny spells peaks in April at 46%, showcasing the arrival of spring, while winter months consistently see reduced chances. Comparatively, December’s sunshine probability is modestly higher than January, February, and November, suggesting that while shorter days and cooler temperatures prevail, there is still a glimmer of hope for bright, sunny moments to brighten the winter landscape.

Percentage of Sunny Days in December in Caernarfon

The chart illustrates the percentage of sunny days in Caernarfon 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 Caernarfon experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec22%25%25%46%30%25%35%24%20%17%19%23%
Data source: Caernarfon December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Caernarfon in December

In Caernarfon, the rhythm of daylight dances through the seasons, culminating in a December when the sun graces the skies for just 7 hours each day. This is a notable reduction from November’s 8 hours, signaling the deepening embrace of winter. As the year progresses, daylight trends show a steady increase from the shortest days of December and January through to the longest days of June and July, where sunlight bathes the landscape for a generous 16 hours. After the summer peak, the days gradually wane again, paving the way for the return to winter darkness. This cyclical pattern not only marks the passage of time but also invites residents and visitors alike to savor each fleeting moment of daylight during the chilly December days.

Average Daylight Hours in Caernarfon for December

The chart illustrates the variation in daylight duration in Caernarfon throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 8m9h 50m11h 54m14h 1m15h 53m16h 52m16h 20m14h 39m12h 37m10h 31m8h 37m7h 36m
Data source: Caernarfon daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Caernarfon

In December, Caernarfon experiences a noticeable uptick in wind speed compared to the calmer summer months. With an average wind speed of 5.0 m/s (11 mph), December stands out as a period of increased breeziness, inviting the crispness of the winter air. Following the more variable speeds of autumn, where October peaked at 5.5 m/s, December maintains a steady and invigorating wind flow that's reminiscent of the earlier months of the year, like February with 5.8 m/s. This consistent gustiness contributes to a lively atmosphere across the scenic coastal town, making it a refreshing time to enjoy the majestic views while feeling the chill of the season.

Average December Wind Speed in Caernarfon

The chart displays monthly wind speed patterns in Caernarfon, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.65.85.23.34.03.82.73.83.35.54.85.0 m/s
Data source: Caernarfon December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Caernarfon Compares to Other Months

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

In December, temperatures typically range from a chilly -1°C (30°F) at night to a mild 13°C (56°F) during the day, with an average of 7°C (45°F). The month sees significant rainfall, with 129 mm (5.1 in) of precipitation across 20 days, accompanied by consistently high humidity levels of 89%.

In contrast, January experiences slightly cooler temperatures, with a minimum of -3°C (27°F) and an average of 6°C (43°F), while still reaching up to 14°C (57°F) at its warmest. Precipitation decreases to 77 mm (3.0 in) over 13 days, but humidity remains steady at 89%. For more detailed information, you can check Caernarfon weather in January.

December weather is generally milder with average temperatures ranging from -1°C (30°F) to 13°C (56°F) and a high precipitation level of 129 mm (5.1 in) over about 20 days. The humidity is quite high at 89%, contributing to a damp atmosphere. In contrast, February experiences slightly cooler temperatures, with lows reaching -4°C (26°F) and highs peaking at 18°C (65°F), yet it has lower overall precipitation at 103 mm (4.1 in) spread over 16 days. The humidity remains similar at 88%, but there's a notable increase in the maximum temperature compared to December. For more detailed information, check out Caernarfon weather in February.

In December, the weather presents a cooler atmosphere with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F), and an average temperature of 7°C (45°F). This month also sees considerable precipitation, totaling 129 mm (5.1 in) over 20 days, accompanied by high humidity at 89%. In contrast, March experiences slightly lower minimum temperatures, dipping to -5°C (23°F), but offers a warmer maximum of 18°C (65°F), maintaining the same average of 7°C (45°F). With less precipitation at 104 mm (4.1 in) over 18 days and humidity dropping to 86%, March feels a bit more pleasant and drier compared to December. For a detailed look at weather conditions during March, visit Caernarfon weather in March.

In December, the weather is quite chilly, with average temperatures hovering around 7°C (45°F), and a maximum of only 13°C (56°F). This month experiences significant precipitation, totaling 129 mm (5.1 in) over about 20 days, and maintains high humidity levels at 89%. In contrast, April brings a noticeable shift in weather patterns, with average temperatures rising to 9°C (48°F) and a maximum of 22°C (72°F). Precipitation drops significantly to 55 mm (2.2 in) over just 11 days, and humidity also decreases slightly to 84%. For more details, check out Caernarfon weather in April.

In December, the weather is notably colder, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F), and an average temperature of 7°C (45°F). This month also experiences significant precipitation, totaling 129 mm (5.1 in) over 20 days, accompanied by high humidity levels of 89%. In contrast, May offers a much more temperate climate, with temperatures rising from a minimum of 0°C (32°F) to a maximum of 28°C (82°F), averaging around 12°C (53°F). Precipitation is lower, at 71 mm (2.8 in) over just 12 days, and humidity drops to 79%. For a closer look at the pleasant conditions in May, check out Caernarfon weather in May.

The weather in December is markedly colder and wetter compared to June. With average temperatures ranging from a chilly 7°C (45°F) to a maximum of 13°C (56°F), December experiences significant precipitation at 129 mm (5.1 in) over about 20 days, accompanied by high humidity levels of 89%. In contrast, June enjoys milder temperatures, with a minimum of 5°C (41°F), averaging 15°C (59°F), and reaching up to a warm 29°C (84°F). Precipitation in June is lower at 91 mm (3.6 in) across 14 days and the humidity is also relatively comfortable at 81%. For more details, you can explore Caernarfon weather in June.

December and July present strikingly different weather conditions. In December, temperatures can dip to a chilly -1°C (30°F), with an average of about 7°C (45°F) and a maximum of 13°C (56°F). The month is also marked by high humidity at 89% and frequent rain, with precipitation occurring on 20 days and totaling 129 mm (5.1 inches). In contrast, July brings much warmer weather, with temperatures ranging from a minimum of 7°C (45°F) to a comfortable maximum of 29°C (85°F) and an average of 16°C (61°F). This summer month is relatively drier, featuring 82 mm (3.2 inches) of precipitation over 15 days, and the humidity is lower at 78%. For more details, check out Caernarfon weather in July.

In December, the weather is notably cooler, with average temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F). This month experiences higher precipitation levels, averaging 129 mm (5.1 in) over 20 days, contributing to a humidity of 89%. In contrast, August offers much milder conditions, with temperatures ranging from a minimum of 8°C (46°F) to a maximum of 26°C (79°F). Precipitation is slightly less in August, at 105 mm (4.1 in) over just 19 days, and the humidity is lower at 79%. For more specific details, you can check Caernarfon weather in August.

December and September present quite contrasting weather conditions. In December, temperatures can dip to a minimum of -1°C (30°F) and typically average around 7°C (45°F), making it significantly chillier than September, which enjoys a more moderate range with a minimum of 3°C (38°F) and an average of 14°C (57°F) that can peak at a comfortable 27°C (81°F). Precipitation levels are also higher in December, averaging 129 mm (5.1 in) over 20 days, compared to September’s 98 mm (3.9 in) spread across 15 days. Additionally, December’s humidity reaches 89%, slightly higher than September’s 85%, adding to the colder feel of winter. For a more detailed look at September weather, check out Caernarfon weather in September.

In comparing the weather between December and October, we see a notable shift in temperatures and conditions. December tends to be colder, with average temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F), while October enjoys milder conditions, with averages from -2°C (29°F) to a warm max of 22°C (71°F). Both months experience similar levels of precipitation, with December receiving 129 mm (5.1 in) over 20 days and October slightly less at 128 mm (5.1 in) over 18 days. Humidity levels are also high in both months, peaking at 89% in December and slightly higher at 90% in October. For more detailed information, you can check Caernarfon weather in October.

In comparing the weather between December and November, we see that December tends to be slightly cooler, with average temperatures ranging from a minimum of -1°C (30°F) to a maximum of 13°C (56°F), compared to November's averages of -1°C (31°F) to 15°C (60°F). Both months experience similar humidity levels, with December averaging 89% and November at 91%. Precipitation is more frequent in December, occurring on 20 days with a total of 129 mm (5.1 in), while November sees slightly less with 111 mm (4.4 in) over 19 days. For more details, check out Caernarfon weather in November.

Compare Caernarfon's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Caernarfon

As December rolls into Caernarfon, a distinct chill sets in, marking a departure from the milder months earlier in the year. With temperatures dipping to their lowest averages, the month is characterized by cool, damp weather, where humidity levels soar to 89% and rainfall becomes a frequent companion, gracing the town on 20 days and delivering significant precipitation. This transition not only showcases the dramatic shifts in climate but also invites a cozy atmosphere, perfect for embracing the festive spirit. For a deeper understanding of how December fits into the overall pattern of Caernarfon's weather, check out Caernarfon Climate.