Last updated: August 21, 2025
December in Castletown, Isle of Man presents a mild coastal climate characterized by an average temperature of 9°C (48°F), with maximums reaching up to 13°C (56°F) and dipping to a minimum of 4°C (39°F). The month experiences substantial precipitation, averaging 144 mm (5.7 in) over 22 days, contributing to a notably humid atmosphere with levels around 89%. Visitors should be prepared for frequent rain showers while enjoying the charm of this picturesque town during the festive season.
In December, Castletown, Isle of Man, experiences a gradual dip in temperatures as winter settles in. With minimums averaging around 4°C (39°F) and daytime highs reaching up to 13°C (56°F), the month embraces a cool atmosphere, giving way to crisp, fresh air. The average temperature of 9°C (48°F) reflects a slight decline from the preceding months, indicating the shift towards the chill of winter. December's milder temperatures remain relatively consistent, similar to November, creating a calm and inviting climate for both residents and visitors. As the festive season unfolds, the scenery transforms into a picturesque wintry landscape, making Castletown a delightful place to experience the end of the year.
December in Castletown, Isle of Man, marks a notable peak in precipitation, with 144 mm (5.7 in) of rain falling over an average of 22 days. This trend sees December surpassing both October and November, which recorded 142 mm and 143 mm respectively. The rising precipitation levels as the year progresses highlight winter's gripping hold on the island, with rain becoming a frequent companion. The increase in both the amount and the number of rainy days in the month reflects the shifting seasons, transforming landscapes into lush, vibrant scenery, while also hinting at the challenges of winter weather. As the year draws to a close, it's clear that December brings a wet curtain call to the annual cycle in Castletown.
In December, Castletown, Isle of Man experiences a notable humidity level of 89%, reflecting a pattern of increased moisture as the year comes to a close. This month sits just below the peak of 91% reached in November, marking a slight decline yet maintaining a high degree of moisture. Compared to earlier months, the humidity shows a gradual decrease from autumn, dipping from October's 90% and November's higher readings. This trend highlights a seasonal transition, with December continuing the trend of elevated humidity common in the winter months, offering a testament to the island's maritime climate.
As December rolls into Castletown, Isle of Man, the UV Index dips back to 1, indicating a low exposure category and a leisurely burn time of 45 minutes. This decline follows a vibrant summer where the index peaked at 8 during June and July, enveloped in a very high exposure category. The trend throughout the year shows a clear seasonal cycle: while early months like January and November maintain low levels, the spring and summer months witness a significant uptick in UV radiation, necessitating increased sun protection for shorter durations. As daylight hours begin to wane, December's return to lower UV levels allows for a breath of fresh air without the urgency of summer sun safety measures. For more detailed insights on the UV patterns throughout the year, visit Castletown UV Index.
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In Castletown, Isle of Man, December offers a gentle conclusion to the year, with about 104 hours of sunshine illuminating the shorter days. This month follows a significant drop from the November peak of 131 hours, reflecting the region's classic winter patterns. As the days grow colder, the sunshine dwindles, displaying a clear trend of diminishing daylight that started from the vibrant heights of spring and early summer, which saw over 400 hours of sunshine. While December's light may be modest compared to the sun-drenched days of July and May, it still provides a soft embrace of warmth and brightness against the backdrop of winter's chill. This subtle shimmer of sunshine invites a cozy atmosphere, perfect for reflecting on the year past in the charming coastal town.
In Castletown, Isle of Man, the chances of sunny weather in December dip to a modest 21%, continuing a downward trend from the previous months. This follows closely after November's already low rate of 22%, suggesting that as winter sets in, the likelihood of clear skies diminishes. Interestingly, while April boasts the highest chance at 52%, summer months like May and July only see moderate sun, reflecting the area’s temperate climate. Overall, December tends to be one of the cloudier months, as the year winds down to a close and residents are more likely to expect overcast skies than bright, sunny days.
As December settles in Castletown, Isle of Man, the days draw shorter, offering just seven hours of daylight. This reduction marks a noticeable dip from the eight hours in November, following a gradual decline from the vibrant seventeen hours enjoyed in June. The trend paints a clear picture of seasonal shifts, as the daylight dwindles through the autumn months, ultimately reaching its nadir in the heart of winter. However, this cozy, dimming light sets the stage for festive celebrations and the quiet beauty of shorter days, reminding us of the natural ebb and flow of time throughout the year.
As winter settles in, the December winds in Castletown, Isle of Man, shift to an average speed of 9.1 m/s (20 mph), reflecting a trend toward brisker conditions compared to the milder months of summer. With the wind speed gradually increasing from a low of 4.3 m/s (10 mph) in July, December's gusts mark a notable return to the stronger breezes typical of the colder season. This uptick aligns with the autumn months of October and November, both witnessing a consistent average of 9.3 m/s (21 mph), suggesting that the Isle of Man experiences a robust airflow as the year wraps up. Thus, December's winds, while slightly lower than the preceding months, still carry the refreshing chill of winter, invigorating the landscape with their persistent presence.
Weather in Castletown varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Castletown, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather between December and January, both months experience similar maximum temperatures, peaking at 13°C (56°F). However, December's average temperature is slightly warmer at 9°C (48°F) compared to January's average of 8°C (46°F). Precipitation is notably higher in December, with 144 mm (5.7 in) falling over 22 days, while January sees a decrease with 81 mm (3.2 in) over just 14 days. Humidity remains consistent at 89% for both months, contributing to the overall dampness typical of this time of year. For more detailed insights on January's weather, you can visit Castletown weather in January.
In comparing the weather between December and February, December tends to be slightly warmer with average temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F). In contrast, February experiences lower average temperatures, with a minimum of 1°C (34°F) and a maximum of 12°C (54°F). Additionally, December sees more precipitation, with 144 mm (5.7 in) spread across 22 days, compared to February's 106 mm (4.2 in) over 18 days. Both months exhibit high humidity, with December at 89% and February slightly lower at 88%. For detailed information on February weather, visit Castletown weather in February.
December weather is characterized by relatively mild temperatures, with a minimum of 4°C (39°F) and an average of 9°C (48°F), peaking at a maximum of 13°C (56°F). However, it is also quite wet, with 144 mm (5.7 in) of precipitation over 22 days, contributing to high humidity levels of 89%. In contrast, March sees cooler temperatures, with a minimum dipping to -1°C (30°F) but an average of 7°C (45°F) and a maximum of 11°C (52°F). Precipitation is lower at 87 mm (3.4 in) over 18 days, with humidity slightly decreased at 86%. The transition from December to March marks a shift to cooler, but slightly drier weather. For a detailed look at March weather, you can refer to Castletown weather in March.
In comparing the weather between December and April, we see that both months share similar maximum temperatures, peaking at around 13°C (56°F). However, December tends to be slightly milder on average with temperatures ranging from a minimum of 4°C (39°F) to an average of 9°C (48°F), contrasting with April's average of 8°C (47°F) and a minimum of 3°C (38°F). Precipitation levels also differ significantly; December experiences much higher rainfall, totaling 144 mm (5.7 in) over 22 days, whereas April has a much drier climate with only 36 mm (1.4 in) over 8 days. Additionally, humidity levels are generally higher in December at 89% compared to April's 84%. For a detailed look into April weather, you can explore Castletown weather in April.
In December, the weather tends to be quite chilly, with average temperatures ranging from 4°C (39°F) to a maximum of 13°C (56°F). This cold month is marked by significant precipitation, totaling 144 mm (5.7 inches) over about 22 days, and a humidity level of 89%, contributing to a damp atmosphere. In contrast, May brings a noticeable warming trend, with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 16°C (60°F). The month is much drier, with only 44 mm (1.7 inches) of precipitation over 9 days and lower humidity at 79%. For a more detailed look at the weather during this spring month, you can check Castletown weather in May.
In December, the weather is generally cooler and wetter, with average temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F). The month sees considerable precipitation, averaging 144 mm (5.7 in) over 22 days, and high humidity levels at 89%. In contrast, June boasts milder temperatures, with averages between 9°C (49°F) and 17°C (64°F), and significantly less rainfall, totaling 70 mm (2.8 in) over just 11 days, along with a lower humidity of 81%. For a detailed look at the June climate, check out Castletown weather in June.
In December, Castletown experiences a significantly chillier climate with average temperatures ranging from 4°C (39°F) to 13°C (56°F) and 144 mm (5.7 in) of precipitation over 22 days, resulting in an overall humidity of 89%. In contrast, July boasts milder conditions, with temperatures generally between 12°C (53°F) and 19°C (67°F). The summer month sees less rainfall, totaling 70 mm (2.8 in) over about 12 days, accompanied by a lower humidity level of 78%. For more detailed insights about the weather in Castletown during July, you can visit Castletown weather in July.
The weather in December contrasts significantly with that of August. In December, temperatures are cooler, with a minimum of 4°C (39°F), an average of 9°C (48°F), and a maximum of 13°C (56°F). Additionally, this month experiences a higher level of precipitation, totaling 144 mm (5.7 in) over 22 days, and a humidity level of 89%, making it quite damp. In contrast, August offers milder temperatures, ranging from a minimum of 12°C (54°F) to a maximum of 18°C (65°F), with an average of 15°C (59°F). Precipitation in August is lower at 94 mm (3.7 in) across 15 days, coupled with a more comfortable humidity of 79%. For detailed insights on the weather during this summer month, check out Castletown weather in August.
December weather tends to be considerably cooler than that of September. In December, temperatures range from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), with an average of 9°C (48°F). The month sees significant rainfall, totaling around 144 mm (5.7 in) across 22 days, and maintaining a high humidity level of 89%. In contrast, September experiences milder temperatures, with a minimum of 10°C (51°F) and a maximum of 19°C (67°F), an average of 14°C (58°F), and less precipitation at 91 mm (3.6 in) over 14 days, along with a slightly lower humidity of 85%. For more details on September's conditions, you can visit Castletown weather in September.
When comparing the weather in December to October, December tends to be colder, with temperatures ranging from a minimum of 4°C (39°F) to an average of 9°C (48°F) and a maximum of 13°C (56°F). In contrast, October's milder climate features temperatures that range from a minimum of 7°C (45°F) to an average of 13°C (55°F) and reaching up to 17°C (63°F). Both months experience similar levels of precipitation, with December receiving 144 mm (5.7 in) over 22 days and October slightly less at 142 mm (5.6 in) over 18 days. Humidity remains high throughout both months, hovering around 89% in December and 90% in October. For more details, you can check Castletown weather in October.
December experiences slightly cooler temperatures than November, with average temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), compared to November's range of 6°C (43°F) to 14°C (58°F). Both months see similar amounts of precipitation, with December receiving 144 mm (5.7 in) over 22 days, just a touch more than November's 143 mm (5.6 in) over 20 days. Humidity remains high in both months, with December averaging 89% compared to November's slightly higher 91%. For more detailed insights, you can visit Castletown weather in November.
December in Castletown marks a notable shift in weather patterns, characterized by cooler temperatures and higher humidity levels than the preceding months. With an average of 9°C and frequent rainfall contributing to a total precipitation of 144 mm, it's a month where the landscape is often cloaked in mist and moisture. The persistent, damp conditions, with 22 wet days, create a stark contrast to the crisp, clear days of autumn, making December feel particularly brisk and chilly. While the temperatures can reach a mild 13°C, cold spells with minimums around 4°C are not uncommon, urging residents and visitors alike to bundle up. For a deeper look at how Castletown's climate evolves throughout the year, explore more at Castletown Climate.