December Weather in Portmarnock, Ireland

Last updated: March 17, 2025

December in Portmarnock, Ireland presents a chilly yet captivating atmosphere, with maximum temperatures reaching around 13°C (56°F) and dipping to a brisk minimum of -2°C (30°F). The month boasts an average temperature of 7°C (45°F), creating a cool backdrop for festive winter activities. With 85 mm (3.4 in) of precipitation spread over 14 days, rain is a frequent visitor, contributing to the lush greenery that characterizes the region. High humidity levels at 84% enhance the coastal chill, wrapping the seaside town in a damp embrace typical of winter months. Despite the weather, Portmarnock's stunning scenery and vibrant local culture shine through, inviting visitors to experience its unique charm.

December Temperature in Portmarnock

In December, Portmarnock, Ireland experiences a notable chill, with temperatures ranging from a minimum of -2°C (30°F) to a maximum of 13°C (56°F). As the year draws to a close, the average temperature settles around 7°C (45°F), showcasing a gradual decline compared to the milder autumn months. Noteworthy is the transition from November's slightly more forgiving temperatures, indicating a shift towards winter. The coldest nights can be crisp, occasionally dipping below zero, while the days remain cool but bearable, making December a month where warm clothing becomes essential. As winter sets in, the clear distinction in temperatures emphasizes the cool maritime climate of this coastal town.

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

The chart illustrates December temperature patterns in Portmarnock, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec434445485358616157524745
Data source: Temperature data for Portmarnock generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Portmarnock

December in Portmarnock brings a notable increase in precipitation, with an average of 85 mm (3.4 in) falling over 14 days. This marks a trend of heightened rainfall as the year wraps up, following a particularly wet November that recorded 93 mm (3.6 in). As the winter months settle in, the frequency of rain increases, setting a cozy, albeit drizzly scene. With precipitation steadily accumulating during December, residents can expect the characteristic lush, green landscape that Ireland is renowned for. This seasonal shift not only highlights a robust end-of-year rainfall pattern but also emphasizes the coastal climate's tendency towards wetter conditions as winter arrives.

December Precipitation Trends in Portmarnock

The chart displays monthly precipitation patterns in Portmarnock, 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.
JanFebMarAprMayJunJulAugSepOctNovDec537373446269739570799385
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Portmarnock

In December, Portmarnock experiences a relative humidity of 84%, a subtle dip compared to the preceding months, which typically hover around the mid-86% range. This slight decrease reflects the transition into winter, as the air cools and moisture levels subtly shift. Interestingly, the humidity remains fairly consistent throughout the year, with only minor fluctuations; January and February peak at 86% while April and May present lower figures at 85% and 83%, respectively. Overall, the coastal charm of Portmarnock is characterized by a stable humidity trend, providing a damp but refreshing atmosphere that enhances the region's picturesque winter scenery.

December Average Humidity in Portmarnock

This chart illustrates the average monthly humidity levels in Portmarnock, 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.
JanFebMarAprMayJunJulAugSepOctNovDec85%86%86%85%83%85%86%85%86%87%87%84%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Portmarnock

As the year draws to a close, December in Portmarnock, Ireland, sees a return to a low UV Index of 1, indicating minimal sun exposure risks. After a summer peak hitting a very high index of 8 in June and July, when the burn time dipped to just 15 minutes, the UV levels now provide a comfortable reprieve. This trend showcases a transitional decline from the vibrant sun exposure of summer months towards the gentler rays of winter. With a consistent burn time of 45 minutes, December encourages outdoor activities while still promoting sun safety. For a detailed understanding of UV trends throughout the year, explore the Portmarnock UV Index.

Maximum UV Index Levels in Portmarnock for December

The chart shows the monthly maximum UV Index (UVI) for Portmarnock 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.
JanFebMarAprMayJunJulAugSepOctNovDec124578875321
Data source: Portmarnock 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 Portmarnock

December in Portmarnock, Ireland, marks the tail end of a year that showcases a striking trend in sunshine hours. Starting with a modest 80 hours in January, the daylight steadily increases, peaking in the vibrant month of May with an impressive 385 hours. As summer fades into autumn, the hours gradually decline, with August still boasting a substantial 329 hours before falling to 114 hours in November. By December, the count decreases to 91 hours, reflecting the shorter days and the seasonal transition into winter. Despite the drop, December’s sunshine echoes the year’s journey from light to twilight, inviting a warm glow as the festive season approaches.

Monthly Sunshine Duration in Portmarnock: December Highlighted

The December sunshine duration represents the total number of hours Portmarnock 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.
JanFebMarAprMayJunJulAugSepOctNovDec80h145h190h308h385h379h377h329h288h226h114h91h
Data source: Portmarnock December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Portmarnock During December

In December, Portmarnock, Ireland experiences a 23% chance of sunny weather, a figure that reflects a slight increase compared to the preceding months, particularly the colder October (20%) and November (26%). While December’s sunlight likelihood does not reach the brighter heights of spring months like April (44%), it remains consistent with late autumn trends. The dim winter days are a reminder of the shifting seasons, as the chances of sun dip notably in the early part of the year, with January showing just a 27% likelihood. Overall, December offers a modest opportunity for sunny breaks amid the winter chill, encouraging residents and visitors alike to embrace the beauty of this coastal town, even on overcast days.

Percentage of Sunny Days in December in Portmarnock

The chart illustrates the percentage of sunny days in Portmarnock 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 Portmarnock experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec27%21%22%44%33%23%30%23%21%20%26%23%
Data source: Portmarnock December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Portmarnock in December

In Portmarnock, Ireland, the daylight duration experiences a significant transformation throughout the year, peaking in the balmy summer months with up to 16 hours of sunlight in both June and July. As the seasons shift, the days gradually shorten, descending to just 8 hours in November and a chilly 7 hours in December. This decline heralds the onset of winter, where the long, sunlit days give way to the early nights and the crisp, cool air of the holiday season. The contrast between summer's extended daylight and winter's brevity emphasizes the striking seasonal rhythm of this coastal town, making it a unique place to experience the ebb and flow of natural light throughout the year.

Average Daylight Hours in Portmarnock for December

The chart illustrates the variation in daylight duration in Portmarnock throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec8h 5m9h 48m11h 54m14h 3m15h 56m16h 56m16h 24m14h 42m12h 37m10h 29m8h 34m7h 31m
Data source: Portmarnock daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Portmarnock

As December arrives in Portmarnock, Ireland, the coastal winds begin to pick up, with an average speed of 5.0 m/s (11 mph), marking a slight increase from the preceding months. After a series of moderate breezes throughout the year, December's gusts bring a refreshing bite to the air, hinting at the winter season ahead. Notably, the wind speeds generally oscillate between 2.8 m/s in July to a peak of 6.0 m/s in February, showcasing a noticeable decline during the summer months when the winds are gentler. The transition into winter not only stirs the atmosphere but also enhances the rugged beauty of Portmarnock's shoreline, inviting both locals and visitors to embrace the dynamic coastal experience.

Average December Wind Speed in Portmarnock

The chart displays monthly wind speed patterns in Portmarnock, 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.
JanFebMarAprMayJunJulAugSepOctNovDec4.66.04.83.53.93.72.83.63.54.84.95.0 m/s
Data source: Portmarnock December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Portmarnock Compares to Other Months

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

In December, temperatures typically range from a chilly minimum of -2°C (30°F) to a comfortable maximum of 13°C (56°F), with an average of 7°C (45°F). The month experiences significant precipitation, averaging 85 mm (3.4 in) over 14 days, and humidity levels hover around 84%. In contrast, January sees slightly cooler temperatures, with a minimum of -3°C (27°F) and a maximum of 14°C (58°F), with an average of 6°C (43°F). Precipitation decreases to 53 mm (2.1 in) over 10 days, and humidity remains high at 85%. For more detailed insights on January weather in Portmarnock, you can visit Portmarnock weather in January.

In comparing December and February weather, both months experience similar minimum temperatures, with December averaging a low of -2°C (30°F) and February also hitting -2°C (29°F). February tends to be slightly warmer at the maximum end, peaking at 15°C (58°F) compared to December's maximum of 13°C (56°F). Precipitation is somewhat less in February, with 73 mm (2.9 in) falling over 14 days, while December sees 85 mm (3.4 in) over the same number of days. Humidity levels are nearly alike, with February averaging 86% compared to December's 84%. For a more detailed look at February weather, check out Portmarnock weather in February.

In December, temperatures in Portmarnock average around 7°C (45°F), with a minimum of -2°C (30°F) and a maximum of 13°C (56°F). The month sees around 85 mm (3.4 in) of precipitation over approximately 14 days, and the humidity stands at a relatively high 84%. In contrast, March experiences similar average temperatures but with a maximum rise to 16°C (62°F). The minimum temperature slightly dips to -3°C (26°F), and precipitation decreases to 73 mm (2.9 in) over the same 14-day period. Humidity is marginally higher in March at 86%. For more detailed information, you can check Portmarnock weather in March.

When comparing the weather in December and April, it's clear that April starts to show signs of warming compared to the brisk chill of December. In December, temperatures range from a chilly -2°C (30°F) at night to a mild 13°C (56°F) during the day, with an average temperature of 7°C (45°F). This month also sees a fair amount of precipitation, with 85 mm (3.4 in) over 14 days, contributing to a high humidity of 84%. In contrast, April offers a bit more warmth, with temperatures ranging from -1°C (31°F) at night to a pleasant 19°C (67°F) during the day, leading to an average of 9°C (48°F). The precipitation decreases significantly to 44 mm (1.7 in) over 11 days, with a similar humidity level of 85%. For a detailed look at the weather specifics in April, you can check out Portmarnock weather in April.

December and May present quite different weather patterns. In December, temperatures range from a chilly -2°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 experiences significant rainfall, with 85 mm (3.4 in) of precipitation spread over 14 days, and humidity remains high at 84%. In contrast, May offers a more temperate climate, with nighttime lows of 1°C (34°F) and daytime highs reaching up to 22°C (72°F), averaging 12°C (53°F). Precipitation decreases to 62 mm (2.4 in) over 12 days, and humidity is slightly lower at 83%. For a closer look at the delightful weather in May, you can visit Portmarnock weather in May.

In December, temperatures in Portmarnock can dip as low as -2°C (30°F) and typically range from an average of 7°C (45°F) to a maximum of 13°C (56°F), with about 85 mm (3.4 in) of precipitation over 14 days. The humidity is fairly high at 84%, contributing to the chilly atmosphere. In contrast, June brings a more temperate climate, with minimum temperatures around 7°C (44°F), averaging 15°C (58°F), and peaking at 25°C (77°F). While June sees less precipitation at 69 mm (2.7 in) over 13 days, the humidity remains similar at 85%, making for a more pleasant and warmer experience. For a detailed look at the June weather specifics, visit Portmarnock weather in June.

In December, the weather is significantly cooler, with temperatures ranging from a minimum of -2°C (30°F) to a maximum of 13°C (56°F), accompanied by higher humidity levels of 84%. This month typically sees about 85 mm (3.4 in) of precipitation over approximately 14 days, creating a chilly and damp atmosphere. In contrast, July offers a much milder climate, with temperatures ranging from a minimum of 8°C (47°F) up to a pleasant 27°C (80°F). The average temperature rests around 16°C (62°F), and although it experiences a fair amount of rain (73 mm or 2.9 in), it generally feels more comfortable with slightly higher humidity at 86%. For more details on July weather in Portmarnock, visit Portmarnock weather in July.

December and August present stark contrasts in weather. December experiences colder temperatures, with minimums dropping to -2°C (30°F) and average highs reaching only 13°C (56°F), while August enjoys milder conditions, with minimums of 8°C (47°F) and maximums peaking at 23°C (74°F). Precipitation is relatively similar, with December receiving 85 mm (3.4 in) over 14 days and August slightly wetter at 95 mm (3.7 in) across 16 days. Both months have high humidity levels, with December at 84% and August slightly higher at 85%. For more detailed information about August weather, you can check out Portmarnock weather in August.

In comparing the weather of December and September, it’s clear they have distinct characteristics. December temperatures range from a minimum of -2°C (30°F) to an average of 7°C (45°F) and a maximum of 13°C (56°F), with relatively high humidity at 84%. This month also sees substantial precipitation, with an average of 85 mm (3.4 in) spread over 14 days. In contrast, September enjoys milder conditions, with temperatures ranging from a minimum of 4°C (39°F) to an average of 14°C (57°F) and a maximum of 22°C (72°F). The month sees slightly less precipitation at 70 mm (2.7 in) over 13 days, accompanied by a marginally higher humidity level of 86%. For more insights into September weather, you can visit Portmarnock weather in September.

In comparing the weather between December and October, December is notably colder, with average temperatures ranging from a minimum of -2°C (30°F) to a maximum of 13°C (56°F). In contrast, October enjoys milder conditions, with temperatures fluctuating between 2°C (36°F) and 19°C (67°F). While both months experience a similar amount of precipitation — 85 mm (3.4 in) in December and 79 mm (3.1 in) in October — December has slightly more rainy days, averaging 14 compared to October's 13 days. Additionally, December's humidity levels are slightly lower at 84%, compared to October's 87%. For more specific details about October weather, you can check Portmarnock weather in October.

In comparing the weather between November and December, we notice a slight drop in average temperatures, with December's average at 7°C (45°F) compared to November's 8°C (48°F). December experiences a minimum temperature of -2°C (30°F), which is a bit colder than November's minimum of -1°C (31°F). Precipitation levels are somewhat similar, with December receiving 85 mm (3.4 in) compared to November's 93 mm (3.6 in); both months also register precipitation on 14 days. Humidity remains high in both months, with December at 84% and November at 86%. For more specific weather details, you can check out Portmarnock weather in November.

Compare Portmarnock's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Portmarnock

As December unfolds in Portmarnock, the weather takes on a distinctly wintry character, contrasting sharply with the milder months preceding it. While temperatures can dip significantly, the air often feels damp with a higher humidity level, resulting in a chill that permeates outdoor activities. Frequent rain contributes to the wet atmosphere, making this month one of the wetter periods of the year with a notable number of precipitation days. If you're planning a visit, it's wise to prepare for both the cold and the occasional downpour, as December encapsulates the essence of the season in this coastal town. For more detailed insights, check out Portmarnock Climate.