Last updated: August 21, 2025
In Castel, Guernsey, December ushers in a chilly embrace, with average temperatures resting at a brisk 11°C (51°F), peaking at a comfortable 14°C (58°F) and dipping to a cool 5°C (41°F). This month marks a significant uptick in precipitation, totaling 163 mm (6.4 in) over 21 rainy days, casting a veil of humidity around 90%. As the season unfolds, residents and visitors alike can expect a blend of dampness and cool temperatures, perfect for cozy indoor pursuits and enjoying the festive cheer.
In December, the temperatures in Castel, Guernsey begin their cool retreat into winter, with a minimum around 5°C (41°F) and an average hovering at 11°C (51°F). As the month progresses, highs reach a comfortable 14°C (58°F), making it a relatively mild conclusion to the year compared to the chilling depths of January and February. The trends from previous months show a gentle decline in temperatures, with December acting as a transitional point before the harsher winter elements set in. Overall, while it's cooler than the fall and summer months, the climate remains pleasantly temperate, allowing for enjoyable outdoor explorations amidst the stunning winter scenery.
In December, Castel, Guernsey experiences a notable uptick in precipitation, with a striking 163 mm (6.4 in) of rain over 21 days—the highest for any month of the year. This surge marks a sharp contrast to the preceding months, particularly when compared to the drier days of April and July, which receive significantly less rainfall. As autumn gives way to winter, the number of rainy days increases, with December often characterized by persistent showers that contribute to the overall annual total. This trend illustrates the island's transition into the wetter winter months, underscoring the importance of preparing for a cold, rainy season ahead.
In December, Castel, Guernsey experiences a notable consistency in humidity, with levels reaching 90%—a figure that aligns closely with the higher humidity observed in both October and November. This winter month marks a continuation of the damp conditions characteristic of the late autumn, as humidity remains elevated compared to the warmer months of July and June, where it dips to a comfortable 63% and 77%, respectively. Notably, as the year progresses from January to May, humidity levels gradually decrease, showcasing the island's transition from brisk winter air to the more temperate surroundings of spring. By December, however, the cycle resets, enveloping Castel in a moist embrace as the year draws to a close.
In December, the UV Index in Castel, Guernsey drops to a mild level of 1, placing it firmly in the low exposure category. This suggests that sun protection is typically not necessary for most outdoor activities, with a burn time of 45 minutes. As the year progresses, a noticeable trend emerges: the UV Index climbs during the spring and summer months, reaching its peak at a very high level of 9 in June. Following the summer's end, the index gradually declines, reinforcing December's status as a month for less sun exposure. As you plan your outdoor activities this winter, remember to check the latest updates for the region at Castel UV Index to stay informed!
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In December, Castel, Guernsey experiences a notable transition as sunshine hours dip to 130—a significant drop from the vibrant 414 hours of sunlight in May. This reduction reflects the natural ebb and flow of daylight throughout the year, culminating in the shorter days of winter when the charm of the season is felt in a different light. Despite the diminished sunshine, the cozy atmosphere of December invites locals and visitors alike to embrace the beauty of winter, showcasing that even in its darkest hour, Castel retains a unique allure. As the year wraps up, residents look forward to brighter months ahead, ready to welcome the gradual return of the sun in the coming spring.
In December, Castel, Guernsey experiences a modest likelihood of sunny weather, with a chance of sunshine at 26%. While this marks a slight decline compared to the previous months, it reflects a broader trend of diminishing daylight and warmth as winter sets in. Notably, the sun is more likely to shine consistently in the spring months, peaking at 62% in April before gradually tapering off. This December statistic underscores the cooler season's grip, highlighting that while sunshine is less frequent, it remains a cherished possibility amidst the winter scenery.
In Castel, Guernsey, daylight hours fluctuate significantly throughout the year, reflecting the changing seasons in this charming locale. December sees daylight return to its 8-hour minimum, mirroring January's scenario. This period marks a gentle transition from the vibrant autumn months, where daylight gradually diminishes from 15 hours in May to merely 8 hours. As the year progresses, the lengthening days begin in March with 11 hours of daylight, peaking in June at a splendid 16 hours, before tapering down again as winter approaches. This rhythmic cycle not only influences daily life but also enriches the beauty of the island’s winter landscapes, inviting both locals and visitors to appreciate the serene charm of a shorter day.
As December settles in over Castel, Guernsey, the island experiences a notable surge in wind intensity, with average wind speeds reaching 9.8 m/s (22 mph). This increase marks a departure from the milder breezes of summer and early autumn, where wind speeds hovered around 4.6 to 8.2 m/s. Notably, December’s gusts are the strongest since the 9.1 m/s (20 mph) recorded in February, highlighting a seasonal shift toward the more vigorous winds typical of winter. The transition is palpable, as the once gentle summer zephyrs give way to the invigorating chill of December’s bluster, inviting both locals and visitors to embrace the brisk coastal air and the vibrant character of the island during this time of year.
Weather in Castel varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Castel, focusing on differences in temperature, rainfall, humidity, and UV levels.
December weather tends to be slightly milder than January, with average temperatures reaching up to 11°C (51°F) compared to January's average of 9°C (49°F). December also experiences higher rainfall, with 163 mm (6.4 in) over 21 days, in contrast to January's 94 mm (3.7 in) across 14 days. Both months maintain high humidity levels around 89-90%, but January brings a slight decrease in precipitation and a cooler feel overall. For more detailed insights about January weather, you can visit Castel weather in January.
December weather tends to be slightly warmer, with average temperatures ranging from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), compared to February's cooler range of 0°C (33°F) to 13°C (56°F). While both months experience significant precipitation, December sees a higher total of 163 mm (6.4 in) over 21 days, whereas February's rainfall is notably less at 86 mm (3.4 in) across 16 days. Humidity levels remain high in both months, with December at 90% and February at 88%. For more detailed insights, you can refer to Castel weather in February.
December and March present contrasting weather patterns. In December, temperatures range from a mild minimum of 5°C (41°F) to a maximum of 14°C (58°F), accompanied by high humidity at 90% and significant precipitation, totaling 163 mm (6.4 in) over 21 days. This leads to a damp and chilly atmosphere typical of late autumn. In contrast, March sees cooler temperatures, with a minimum of 0°C (32°F) and a maximum of 13°C (55°F). While precipitation is lower at 73 mm (2.9 in) over 15 days and humidity also decreases to 85%, the weather begins to hint at the arrival of spring. For more specific details, you can check Castel weather in March.
December and April present contrasting weather patterns. In December, temperatures range from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), with an average of 11°C (51°F). The month is characterized by significant rainfall, totaling 163 mm (6.4 in) over 21 days, and a high humidity level of 90%. In contrast, April sees slightly cooler temperatures, with a minimum of 5°C (41°F) and a maximum of 15°C (59°F), averaging 10°C (50°F). Rainfall is considerably less in April, at just 34 mm (1.3 in) across 8 days, and humidity drops to 84%. For more detailed information on the weather in April, you can refer to Castel weather in April.
December and May present quite contrasting weather patterns. In December, temperatures range from a chilly minimum of 5°C (41°F) to a mild maximum of 14°C (58°F), with an average temperature of 11°C (51°F). The month also witnesses significant rainfall, with 163 mm (6.4 in) spread over 21 days, contributing to a high humidity level of 90%. In comparison, May tends to be warmer, with temperatures starting at a minimum of 7°C (45°F) and reaching up to 18°C (65°F), averaging at 12°C (54°F). Additionally, May is much drier, with only 55 mm (2.2 in) of precipitation occurring over just 8 days, and humidity levels are more moderate at 81%. For a more detailed look at the weather in May, you can visit Castel weather in May.
December and June present strikingly different weather conditions. In December, temperatures are cooler, ranging from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), with an average of 11°C (51°F). This month experiences significant rainfall, averaging 163 mm (6.4 inches) across 21 days, coupled with high humidity at 90%. In contrast, June offers a milder climate with temperatures starting at 11°C (53°F) and peaking at 19°C (67°F), averaging 14°C (58°F). Rainfall is considerably lower, totaling 59 mm (2.3 inches) over just 8 days, and humidity drops to a more comfortable 77%. For more details, check out Castel weather in June.
December and July present stark contrasts in weather conditions. In December, temperatures range from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), with an average of 11°C (51°F). The month is characterized by significant precipitation, totaling 163 mm (6.4 in) over 21 days, coupled with high humidity levels at 90%. In contrast, July offers a milder climate, with temperatures ranging from 14°C (57°F) to 21°C (70°F) and an average temperature of 16°C (62°F). Rainfall is considerably lower in July, with only 37 mm (1.5 in) spread across just 7 days, and humidity levels decrease to a more comfortable 63%. For a detailed overview of July weather, visit Castel weather in July.
In December, temperatures tend to be much cooler, with a minimum of 5°C (41°F) and an average of 11°C (51°F), reaching a maximum of 14°C (58°F). The month is characterized by significant rainfall, with 163 mm (6.4 in) spread over 21 days and high humidity levels at 90%. In stark contrast, August experiences much milder conditions, with minimum temperatures around 14°C (57°F) and an average of 17°C (63°F), peaking at 22°C (72°F). Precipitation is considerably lower at 50 mm (2.0 in) and occurs on only 9 days, coupled with a more comfortable humidity level of 71%. For a closer look at August weather, you can visit Castel weather in August.
December weather is significantly cooler and wetter compared to September. While December's temperatures range from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), September enjoys milder conditions with temperatures ranging from 12°C (54°F) to 21°C (71°F). Additionally, December experiences much more precipitation, with 163 mm (6.4 in) falling over 21 days, whereas September sees only 63 mm (2.5 in) over just 9 days. The humidity is also higher in December at 90%, compared to September's 76%. For more detailed insights into September's weather, visit Castel weather in September.
Comparing the weather in December and October, we see notable differences in temperature and precipitation. December is generally cooler, with minimum temperatures around 5°C (41°F) and an average high of 14°C (58°F), while October enjoys slightly warmer conditions, with lows of 9°C (48°F) and highs reaching 20°C (68°F). Additionally, December experiences more rainfall, accumulating about 163 mm (6.4 in) over 21 days, compared to October’s 144 mm (5.7 in) over 17 days. Humidity levels are similar, hovering around 90% in December and 89% in October. For a more detailed look at October weather, you can check out the following link: Castel weather in October.
In comparing the weather of December and November, we see that December is slightly cooler, with average temperatures ranging from a minimum of 5°C (41°F) to a maximum of 14°C (58°F), whereas November showcases slightly warmer averages, with temperatures ranging from a minimum of 6°C (43°F) to a maximum of 17°C (63°F). December also experiences more precipitation, totaling 163 mm (6.4 in) over 21 days, compared to November's 126 mm (5.0 in) across 18 days. Both months maintain high humidity levels at 90%, contributing to a damp and chilly atmosphere. For more details on November's weather, you can visit Castel weather in November.
As December settles in Castel, the weather experiences a noticeable shift from the milder conditions of preceding months. Average temperatures dip, ushering in a chill that lingers with highs around 14°C and lows sinking to 5°C. This month is markedly wetter, with frequent rainfall gracing 21 days, culminating in a total precipitation of 163 mm. Coupled with a high humidity level of 90%, December offers a damp and cool atmosphere that stands in stark contrast to the warmer, drier months of the year. For a deeper understanding of how these conditions shape life in Castel, check out Castel Climate.