Last updated: August 21, 2025
December in Mariehamn, Åland Islands showcases a crisp winter ambiance with temperatures ranging from a maximum of 7°C (46°F) to a chilly minimum of -8°C (19°F). The average temperature lingers around 3°C (37°F), providing a brisk backdrop for the holiday season. This month brings significant precipitation, totaling 80 mm (3.1 in) over approximately 18 days, contributing to the region’s 87% humidity. Visitors can expect a blend of wintry weather, making it ideal for cozy gatherings and scenic outdoor activities.
In December, Mariehamn, Åland Islands, experiences the cold embrace of winter with temperatures that reflect a gradual drop as the year draws to a close. The month typically sees minimums around -8°C (19°F), while the average hovers close to 3°C (37°F), providing a crisp, frosty atmosphere. Maximum temperatures cap at around 7°C (46°F), indicating that winter is well and truly settled in. Notably, this marks a continuation of the trend from November, where temperatures begin dipping, signaling the onset of more frigid conditions. The chilly December air often invites the charm of festive decorations and cozy gatherings, making it a picturesque time in this serene island environment.
In December, Mariehamn experiences a notable shift in precipitation patterns, with 80 mm (3.1 in) of rainfall spread over 18 days. This is a significant increase compared to the previous months, highlighting the transition to the winter season. As the year comes to a close, December's precipitation is effectively poised between the wetter autumn months, like October with 90 mm (3.6 in), and the drier spring months ahead. The increased frequency of rainfall days indicates the onset of holiday season gloom, making the air feel crisp and moist. While precipitation peaks in autumn, December reminds us of the persistent presence of winter's embrace, leaving behind a transformative landscape marked by a blend of rain and the first whispers of seasonal snow.
In Mariehamn, Åland Islands, December marks a transition into the cooler months, where humidity levels settle at a comfortable 87%. This is a slight dip from the high humidity of 90% observed in November, continuing a trend of gradually decreasing moisture from the previous summer's low of 74% in July. Over the year, humidity levels remain relatively high, particularly during the winter months, indicating a consistent maritime influence on the climate. Interestingly, the winter months of January and February maintain high humidity levels, hovering close to 90%, while the late spring months of May and June offer a refreshing relief with their lowest readings at 77%. This rhythm emphasizes the character of Mariehamn's climate, marked by humid winters and milder, drier summers.
In December, Mariehamn experiences a low UV Index of 1, which aligns with the winter months where sun exposure poses minimal risks. As the year progresses from winter to summer, the UV Index shows a notable increase, rising from 1 in January to a peak of 7 during the sun-soaked months of June and July. This trend highlights the importance of monitoring UV exposure, especially as the seasons shift; while December offers ample protection with a burn time of 45 minutes, those planning to enjoy outdoor activities in the summer must be more vigilant with only 25 minutes of safe sun exposure. For more detailed insights into UV levels throughout the year, visit Mariehamn UV Index.
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In Mariehamn, Åland Islands, December offers a modest 73 hours of sunshine, a stark contrast to the sun-drenched peak summer months, where July boasts a remarkable 493 hours. As autumn deepens, the daylight dims significantly, with November witnessing only 134 hours of sunshine before the winter envelops the archipelago. This trend illustrates a gradual decline in daylight hours as the year progresses, transitioning from the vibrant brightness of spring and early summer—where April records 368 hours—to the hushed, wintry days of December. Despite the shorter days, the serene winter landscape invites a unique charm, making each fleeting ray of sunshine a precious gem in the heart of the season.
In December, the likelihood of sunny weather in Mariehamn, Åland Islands, drops to a modest 19%, marking one of the least sunlit months of the year. This trend aligns with a general decline in sunshine opportunities as the year winds down; after enjoying peak sunshine in the summer months, where July boasts a 62% chance, the probabilities steadily decrease through the autumn. As the cold grips the islands, December's shorter days and cloudier skies find residents settling in for winter, anticipating the brighter possibilities of the coming spring.
In Mariehamn, Åland Islands, the daylight duration undergoes a captivating transformation throughout the year. As winter approaches in December, the sun graces the sky for just 5 hours, marking the year's lowest point of daylight. This reduction follows a steady decline from the brighter months of June, where sunlight extends to a delightful 18 hours. From the heart of winter, days slowly lengthen into January with 6 hours, and gradually reach 9 hours by February. The transition into spring reveals a notable increase, peaking in May with a generous 17 hours of daylight. As the year wanes, Håland’s long summer evenings give way to cozy winter nights, highlighting the rhythmic dance of daylight that characterizes life in this enchanting archipelago.
In December, Mariehamn experiences a lively shift in its winds, with an average speed of 7.9 m/s (18 mph), reflecting a notable increase as the year comes to a close. This uptick follows a consistent pattern observed through the autumn months, with October boasting the highest winds at 9.1 m/s (20 mph). As the air turns crisper, the winds from November’s 7.8 m/s transition smoothly into December, hinting at the changing seasons. The brisk winds not only invigorate the landscape but also prepare the islands for the chill of winter, showcasing a dynamic climate that dances through the transition from fall to winter. Overall, December's winds continue the trend of autumn’s playful breezes, making Mariehamn an exhilarating destination during this season.
Weather in Mariehamn varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Mariehamn, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather is characterized by a range of temperatures that typically spans from a minimum of -8°C (19°F) to a maximum of 7°C (46°F), with an average temperature around 3°C (37°F). During this month, there is significant precipitation of 80 mm (3.1 in) over 18 days, contributing to a humidity level of 87%. In contrast, January sees slightly colder conditions with an average temperature dropping to 1°C (35°F) and a similar maximum of 8°C (46°F). However, January experiences less precipitation, totaling 48 mm (1.9 in) over just 11 days, and a higher humidity level of 90%. For more detailed insights into January's conditions, you can visit Mariehamn weather in January.
In December, the weather is characterized by milder temperatures, with an average of 3°C (37°F) and a maximum of 7°C (46°F), compared to February’s chillier average of 0°C (33°F). While both months experience low minimum temperatures, December's minimum is slightly warmer at -8°C (19°F) compared to February's colder -10°C (14°F). December also sees more precipitation, with 80 mm (3.1 in) falling over 18 days, whereas February has only 38 mm (1.5 in) across 10 days. Both months have high humidity, but December’s levels are marginally lower at 87%, compared to February’s 88%. For more specific details about February’s climate, you can check out Mariehamn weather in February.
December and March exhibit notable differences in weather patterns. In December, the average temperature hovers around 3°C (37°F), with a maximum of 7°C (46°F) and a minimum of -8°C (19°F). This month experiences significant precipitation, totaling 80 mm (3.1 in) over 18 days, coupled with high humidity at 87%. In contrast, March presents slightly cooler conditions, with an average temperature of 1°C (35°F) and a maximum of 9°C (48°F), but an even lower total precipitation of only 37 mm (1.5 in) over just 9 days, and humidity remains high at 89%. For more detailed insights into March weather, visit Mariehamn weather in March.
December and April exhibit distinct differences in weather patterns. In December, temperatures can plunge to a minimum of -8°C (19°F), while averaging around 3°C (37°F) and reaching a maximum of 7°C (46°F). This month is characterized by significant precipitation, totaling 80 mm (3.1 in) over 18 days, along with high humidity at 87%. In contrast, April sees milder temperatures with a minimum of -1°C (30°F), an average of 3°C (38°F), and a maximum of 9°C (48°F). Precipitation is notably lower in April, with only 24 mm (1.0 in) spread across 7 days, and humidity remains slightly lower at 85%. For more insights on April weather, you can check Mariehamn weather in April.
December and May exhibit contrasting weather patterns, showcasing the transition from winter to spring. In December, temperatures can plummet as low as -8°C (19°F), with an average of 3°C (37°F) and a maximum of 7°C (46°F). The month experiences significant precipitation, totaling around 80 mm (3.1 in) over approximately 18 days, coupled with a high humidity level of 87%. In stark contrast, May sees much milder temperatures, with a minimum of 1°C (33°F), an average of 7°C (45°F), and a maximum of 15°C (59°F). Rainfall significantly decreases to 36 mm (1.4 in), spread over just 6 days, and humidity drops to a more comfortable 77%. For a detailed look at weather conditions during May, you can visit Mariehamn weather in May.
The weather in December is characterized by much colder temperatures, with minimums dropping to -8°C (19°F) and average highs reaching only 7°C (46°F). This month also sees significant precipitation, totaling 80 mm (3.1 in) over approximately 18 days, resulting in a high humidity level of 87%. In contrast, June boasts a milder climate, with minimum temperatures of 7°C (44°F) and pleasant average highs around 21°C (70°F). Additionally, June experiences much less precipitation at just 29 mm (1.1 in) spread over only 4 days, contributing to a lower humidity level of 76%. For more details on the summer weather, check out Mariehamn weather in June.
December and July present stark contrasts in weather. In December, temperatures can dip as low as -8°C (19°F), with an average around 3°C (37°F) and a maximum of 7°C (46°F). The month is characterized by higher humidity at 87% and a significant amount of precipitation, totaling 80 mm (3.1 in) over 18 days. In contrast, July experiences milder conditions, with minimum temperatures around 11°C (53°F) and an average of 17°C (63°F), peaking at 24°C (75°F). The summer month sees only 45 mm (1.8 in) of rain over just 7 days, accompanied by a lower humidity level of 74%. For a more detailed look at the weather during this month, visit Mariehamn weather in July.
When comparing the weather in December and August, it's clear that the two months present quite different climates. December features much colder temperatures, with averages around 3°C (37°F) and nighttime lows dipping to -8°C (19°F). It also sees higher humidity levels at 87% and significant precipitation, with rain or snow occurring on 18 days and accumulating to 80 mm (3.1 in). In contrast, August enjoys milder conditions, offering an average temperature of 17°C (63°F) and maximums that reach up to 23°C (74°F). Precipitation is lighter during this month, with total rainfall reaching only 53 mm (2.1 in) over about 10 days. For more detailed insights, you can visit Mariehamn weather in August.
December and September present contrasting weather conditions. In December, temperatures can dip as low as -8°C (19°F), with an average of 3°C (37°F) and highs reaching only 7°C (46°F). The month also sees significant precipitation, totaling 80 mm (3.1 in) over 18 days, accompanied by high humidity at 87%. In contrast, September enjoys milder temperatures, ranging from a minimum of 8°C (46°F) to a maximum of 20°C (68°F), with an average of 14°C (57°F). Precipitation is lighter, with 56 mm (2.2 in) falling over just 11 days, and humidity is slightly lower at 85%. For more detailed insights, you can visit Mariehamn weather in September.
In comparing the weather between December and October, it's evident that December is significantly colder, with average temperatures hovering around 3°C (37°F) compared to October's milder average of 9°C (49°F). While October enjoys mild highs of up to 15°C (59°F), December's maximum only reaches 7°C (46°F). Precipitation levels are fairly similar, with October receiving 90 mm (3.6 in) over 17 days and December slightly less at 80 mm (3.1 in) over 18 days. Humidity remains high in both months, with December at 87% and October at 89%, resulting in a damp atmosphere typical of late autumn and winter. For more detailed information on October weather, you can visit Mariehamn weather in October.
In comparing the weather between November and December, December tends to be significantly colder, with average temperatures ranging from a minimum of -8°C (19°F) to a maximum of 7°C (46°F), whereas November features milder temperatures, with a low of -2°C (29°F) and a high of 13°C (55°F). Precipitation also increases in December, with 80 mm (3.1 in) falling over 18 days, compared to November's 57 mm (2.2 in) over 14 days. Humidity levels remain similar, with December at 87% and November at 90%, but the overall chill and increase in precipitation make December feel much wetter and colder. For more detailed information about November weather, you can visit Mariehamn weather in November.
As December settles over Mariehamn, the weather reflects a significant shift towards winter, with temperatures dipping to their coldest of the year. This month experiences a blend of chilly temperatures and notable humidity, giving an unmistakable wintry character to the region. Precipitation is more frequent, with rain and snow gracing the landscape and adding to the seasonal atmosphere. In contrast to the milder autumn months, December is marked by its colder averages and increased precipitation days, providing residents and visitors alike a true sense of the approaching winter. For a deeper understanding of what to expect year-round, check out our detailed page on Mariehamn Climate.