December Weather in Port Saint Mary, Isle of Man

Last updated: August 21, 2025

December in Port Saint Mary, Isle of Man, showcases a temperate maritime climate with a maximum temperature of 13°C (56°F) and an average of 9°C (48°F). As the year winds down, expect chilly days with a minimum temperature dipping to 4°C (39°F). This month is characterized by considerable precipitation, totaling 144 mm (5.7 in) spread over 22 days, contributing to the region's lush greenery. Coupled with high humidity levels at 89%, December can feel quite damp, making it a quintessentially wintry month by the coast. Whether you’re exploring the picturesque seaside or enjoying cozy indoor activities, Port Saint Mary’s December offers a unique charm.

December Temperature in Port Saint Mary

As December unfolds in Port Saint Mary on the Isle of Man, temperatures begin to cool, marking the transition into winter. The average temperature settles around 9°C (48°F), with nightly lows dipping to about 4°C (39°F), while daytime highs can reach a mild 13°C (56°F). This month showcases a gradual decline from the milder conditions of autumn, reflecting a consistent drop in temperatures as the year draws to a close. Coastal breezes can add a crisp chill to the air, making those cozy, warm layers a practical choice for anyone enjoying the festive spirit. Overall, December offers a refreshing yet moderate climate, perfect for exploring the scenic beauty of this charming island.

December Weather in Port Saint Mary: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Port Saint Mary, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Port Saint Mary, December typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec464545475155585958555047
Data source: Temperature data for Port Saint Mary 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 Port Saint Mary

December brings a notable increase in precipitation in Port Saint Mary, Isle of Man, with 144 mm (5.7 in) of rainfall, making it one of the wettest months of the year. This trend aligns with the month’s 22 rainy days, the highest of any month, which suggests that December is a time when the island experiences nearly continuous moisture. Following a pattern observed over the fall months, the rainfall peaks in November and December, indicating a shift towards more persistent winter conditions. As the year wraps up, the increase in both precipitation amount and rainy days highlights Port Saint Mary's characteristic dampness during this season, laying the groundwork for a lush landscape as it transitions into the new year.

December Precipitation Trends in Port Saint Mary

The chart displays monthly precipitation patterns in Port Saint Mary, 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. In Port Saint Mary, December typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec8110687364470709492142144144
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Port Saint Mary

December in Port Saint Mary, Isle of Man, sees a notable humidity level of 89%, which aligns closely with the slightly higher readings of the preceding months, particularly November's 91%. As the year draws to a close, humidity remains relatively high compared to the warmer months, with July and August recording the lowest levels at 78-79%. This trend indicates a return to the damp conditions typical of the winter season, reminding residents to prepare for the chilly, moisture-laden atmosphere that defines the Isle of Man during this time of year. Overall, the gradual fluctuations in humidity underscore the area's maritime climate, with winter months generally maintaining elevated levels.

December Average Humidity in Port Saint Mary

This chart illustrates the average monthly humidity levels in Port Saint Mary, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Port Saint Mary is approximately {2}%, offering insight into how humid the weather typically is during this month.
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 Port Saint Mary

In December, Port Saint Mary experiences a low UV Index of 1, indicating minimal sun exposure risk. This trend of decreased UV exposure is consistent as the year comes to a close, following the higher values observed in the summer months. With a burn time of 45 minutes, locals and visitors can enjoy outdoor activities with greater peace of mind, avoiding the need for heavy sun protection typically necessary in the brighter months of May through July when the UV Index peaks at 8. As the colder months descend, maintaining awareness of UV levels remains important; for further information, visit Port Saint Mary UV Index.

Maximum UV Index Levels in Port Saint Mary for December

The chart shows the monthly maximum UV Index (UVI) for Port Saint Mary 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. In December, the maximum UV index in Port Saint Mary typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec123578875321
Data source: Port Saint Mary 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 Port Saint Mary

December in Port Saint Mary, Isle of Man, offers a gentle yet subdued farewell to the year, basking in 104 hours of sunshine. While this reflects a notable dip from the sun-drenched months of June and July, which each recorded 418 hours, it’s part of an expected seasonal trend. As the days grow shorter and winter approaches, the sunlight gradually dwindles from a vibrant 418 hours in May to a modest 90 hours in January. Though December may not boast the bright skies of springtime, it still stands as a serene month, inviting residents and visitors alike to embrace the crisp air and the quiet beauty of the landscape during this transitional period.

Monthly Sunshine Duration in Port Saint Mary: December Highlighted

The December sunshine duration represents the total number of hours Port Saint Mary 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.
JanFebMarAprMayJunJulAugSepOctNovDec90h161h233h341h418h411h418h376h314h244h131h104h
Data source: Port Saint Mary December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Port Saint Mary During December

In December, Port Saint Mary experiences a modest 21% chance of sunny weather, marking it as one of the less promising months for sunlight. This trend towards cloudier conditions is evident as we move from the relatively brighter months of April and May, which boast chances of sun at 52% and 40%, respectively. The likelihood of sun gradually declines from the summer months of July and August, where we see 40%, down to a low 22% in October and November. As December approaches, residents and visitors can expect a significant drop in sunny days, reinforcing the notion of winter’s embrace in this charming coastal town.

Percentage of Sunny Days in December in Port Saint Mary

The chart illustrates the percentage of sunny days in Port Saint Mary 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 Port Saint Mary experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec28%26%25%52%40%29%40%29%24%22%22%21%
Data source: Port Saint Mary December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Port Saint Mary in December

As the year draws to a close in December, Port Saint Mary, Isle of Man, experiences a notable dip in daylight, with only about 7 hours available each day. This decrease is part of an overarching trend, as the region enters the winter months and daylight hours gradually diminish from their peak in June, where they extend to a generous 17 hours. Following a steady decline, November echoes the trend, also seeing just 8 hours of daylight, before plunging to its annual low in December. As the darker months settle in, the contrast from the brighter spring and summer months becomes strikingly apparent, highlighting the seasonal ebb and flow of daylight that characterizes this charming coastal community.

Average Daylight Hours in Port Saint Mary for December

The chart illustrates the variation in daylight duration in Port Saint Mary throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h9h 46m11h 54m14h 5m16h 1m17h 2m16h 29m14h 45m12h 38m10h 28m8h 30m7h 26m
Data source: Port Saint Mary daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Port Saint Mary

As December settles in Port Saint Mary, the wind begins to howl with an average speed of 9.1 m/s (20 mph), marking it as a time when the island braces for the winter's breath. The wind patterns show a noticeable shift, with December holding its ground steady after the autumn months, which both averaged 9.3 m/s. While the earlier months of the year experienced more variable gusts, with February peaking at 10.5 m/s, there’s a clear trend of diminishing winds from the summer’s calmness, where July recorded a gentle 4.3 m/s (10 mph). As the year transitions, December presents itself as a month where the invigorating coastal winds not only signal the festive season but also remind us of the relentless power of nature that characterizes the Isle of Man.

Average December Wind Speed in Port Saint Mary

The chart displays monthly wind speed patterns in Port Saint Mary, 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.
JanFebMarAprMayJunJulAugSepOctNovDec8.510.58.55.86.46.64.35.76.09.39.39.1 m/s
Data source: Port Saint Mary December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Port Saint Mary Compares to Other Months

Weather in Port Saint Mary varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Port Saint Mary, focusing on differences in temperature, rainfall, humidity, and UV levels.

In December, the weather is characterized by slightly milder temperatures, with a minimum of 4°C (39°F) and an average of 9°C (48°F), reaching a maximum of 13°C (56°F). The month experiences significant rainfall, totaling 144 mm (5.7 in) over 22 days, contributing to a high humidity level of 89%. In contrast, January sees a minor drop in temperatures, with a minimum of 3°C (38°F) and average of 8°C (46°F), while still capping at 13°C (56°F). Precipitation decreases notably to 81 mm (3.2 in) over 14 days, while humidity remains constant at 89%. For a detailed look at the weather trends, check out Port Saint Mary weather in January.

December and February both experience relatively cool temperatures, but December is slightly warmer on average. In December, the minimum temperature is around 4°C (39°F) and the average is 9°C (48°F), while February sees a lower minimum of 1°C (34°F) with an average of 7°C (45°F). Precipitation is also more prevalent in December, with 144 mm (5.7 in) falling over 22 days compared to February's 106 mm (4.2 in) across 18 days. Humidity remains high in both months, with December at 89% and February slightly lower at 88%. For more detailed information, check out Port Saint Mary weather in February.

In December, temperatures in Port Saint Mary range from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), with a chilly average of 9°C (48°F). The month sees significant precipitation, totaling 144 mm (5.7 in) over 22 days, contributing to the high humidity of 89%. In contrast, March brings cooler temperatures, with lows dropping to -1°C (30°F) and a slightly warmer upper limit of 11°C (52°F), resulting in an average of 7°C (45°F). Rainfall decreases to 87 mm (3.4 in) across 18 days, and humidity stands at a similar level of 86%. For more insights into March weather, you can check Port Saint Mary weather in March.

In December, the weather tends to be cooler and wetter, with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F). The month sees significant precipitation, averaging 144 mm (5.7 in) over 22 days, and the humidity is notably high at 89%. In contrast, April experiences mild temperatures with an average of 8°C (47°F) and a similar maximum of 13°C (56°F), but it is much drier, receiving only 36 mm (1.4 in) of rain over just 8 days, alongside a slightly lower humidity of 84%. For more detailed information on April's weather, you can visit Port Saint Mary weather in April.

In December, the weather in Port Saint Mary is characterized by cooler temperatures, with averages ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F). The month sees significant precipitation, totaling 144 mm (5.7 in) over 22 days, accompanied by high humidity levels at 89%. In contrast, May experiences milder conditions, with temperatures slightly higher, ranging from a minimum of 5°C (42°F) to a maximum of 16°C (60°F). Precipitation is much lighter in May, with only 44 mm (1.7 in) spread across just 9 days and a reduced humidity of 79%. For a closer look at the specifics of May's weather, check out Port Saint Mary weather in May.

In December, the weather is markedly cooler, with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), and an average of 9°C (48°F). Additionally, the month sees significant precipitation, totaling 144 mm (5.7 in) over about 22 days, leading to a relatively high humidity of 89%. In contrast, June offers milder temperatures, starting at a minimum of 9°C (49°F) and peaking at 17°C (64°F) with an average of 13°C (55°F). The rainfall also decreases significantly in June to 70 mm (2.8 in) spread across just 11 days, and the humidity is slightly lower at 81%. For more detailed information, you can check out Port Saint Mary weather in June.

December and July present markedly different weather conditions. 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 is characterized by high humidity at 89% and significant precipitation, totaling 144 mm (5.7 in) over 22 days, making it a rather wet and chilly time of year. In contrast, July enjoys milder temperatures, with a minimum of 12°C (53°F) and a maximum of 19°C (67°F), averaging around 14°C (58°F). Precipitation is notably lower at 70 mm (2.8 in) across just 12 days, and humidity is more moderate at 78%. For a detailed look at July's weather, you can visit Port Saint Mary weather in July.

When comparing the weather in December and August, it's clear that December is significantly colder and wetter. In December, temperatures range from a chilly minimum of 4°C (39°F) to a maximum of 13°C (56°F), with an average of 9°C (48°F). This month also sees substantial rainfall, with 144 mm (5.7 in) of precipitation over 22 days and high humidity levels at 89%. In contrast, August experiences milder conditions, where temperatures typically range from a minimum of 12°C (54°F) to a maximum of 18°C (65°F), averaging 15°C (59°F). Rainfall is also less frequent in August, with 94 mm (3.7 in) spread over 15 days and lower humidity at 79%. For a more detailed look at August weather, visit Port Saint Mary weather in August.

In comparing the weather of December and September, it is evident that December is significantly cooler and wetter. December experiences a lower average temperature, ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), while September enjoys milder conditions with temperatures from a minimum of 10°C (51°F) to a maximum of 19°C (67°F). Additionally, December sees much higher precipitation, averaging 144 mm (5.7 in) across 22 days, compared to September's 91 mm (3.6 in) over 14 days. Humidity levels are quite similar, with December at 89% and September at 85%. For more detailed September weather information, you can visit Port Saint Mary weather in September.

In comparing the weather between December and October, we see notable differences. December tends to be cooler, with average temperatures ranging from a minimum of 4°C (39°F) to a maximum of 13°C (56°F), while October offers milder conditions, averaging from 7°C (45°F) to 17°C (63°F). Precipitation in both months is similar, with December recording 144 mm over 22 days and October slightly less at 142 mm over 18 days. Humidity levels are comparable, as December sits at 89% and October at 90%. For more detailed insights on October's weather, you can visit Port Saint Mary weather in October.

In comparing the weather between November and December, we see a slight decrease in average temperatures as December's min, avg, and max temperatures are 4°C, 9°C, and 13°C respectively, compared to November's 6°C, 10°C, and 14°C. Precipitation levels are quite similar, with December receiving 144 mm over 22 days, while November records 143 mm over 20 days. Interestingly, December has a lower humidity level at 89%, compared to November's 91%. Overall, both months are characterized by cool temperatures and persistent rainfall. For a closer look at November’s weather conditions, you can refer to Port Saint Mary weather in November.

Compare Port Saint Mary's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Port Saint Mary

As December unfolds in Port Saint Mary, the weather takes on a distinct character, marking the transition to winter. Temperatures drop, with cool days averaging around 9°C, while frequent rainfall keeps the atmosphere moist, contributing to high humidity levels of 89%. With about 22 days of precipitation, this month stands out for its wet and overcast conditions compared to the milder and drier months that precede it. It's a time when cozy indoor retreats become essential, highlighting the charm of winter on the Isle of Man. For more insights into how December blends into the overall climate, check out Port Saint Mary Climate.