Last updated: August 21, 2025
December in Helsinki brings a wintry panorama, characterized by temperatures that hover around a chilly average of -1°C (31°F), with peaks reaching up to 7°C (44°F) and plunges as low as -18°C (0°F). Visitors can expect a fair amount of precipitation, totaling 73 mm (2.9 in) over approximately 15 days of the month, contributing to the city’s picturesque snowy landscapes. With humidity levels soaring at 95%, the air feels crisp and dense, creating a quintessentially Nordic atmosphere perfect for winter activities and cozy indoor gatherings.
In December, Helsinki, Finland wraps itself in a wintry embrace as temperatures plunge, featuring a minimum of -18°C (0°F) and an average around -1°C (31°F). This month stands out as the onset of the harshest winter conditions, with highs barely reaching 7°C (44°F). A stark contrast to the preceding months, December displays a significant drop, continuing the trend of descending temperatures seen from late autumn. The city's landscape transforms into a winter wonderland, inviting residents and visitors alike to experience the serene beauty of snow-covered scenery, though it's essential to bundle up against the chill to fully enjoy all that this season has to offer.
In December, Helsinki experiences a notable shift as it welcomes winter, with precipitation totaling 73 mm (2.9 in) over the month. This amount, while less than the wettest months of October and July, signifies a consistent pattern of winter moisture. December also marks an increase in precipitation days, averaging 15 days, making the city quite lively with intermittent snow and rain. Compared to November's 62 mm and 13 days of precipitation, December sees not only a rise in total precipitation but also an uptick in the frequency of wet days, hinting that winter's embrace is characterized by frequent, if lighter, precipitation events that contribute to the city’s winter charm.
In Helsinki, December marks a notable transition in the city's humidity levels, with an average of 95%—slightly lower than the tail end of autumn but comparable to earlier winter months. As the year winds down, humidity remains consistently high, reflecting the maritime influences of the Baltic Sea. This trend of elevated humidity persists from January through November, peaking in the coldest months, where it hovers around 95% to 97%. Interestingly, the year begins with its highest humidity but gradually trends downwards towards spring, allowing for a brief respite in the dry months of May and June. As December arrives, the atmosphere feels heavy with moisture, a reminder of the approaching depths of winter. Overall, the cycle of humidity in Helsinki underscores the city's unique climate and its connection to the surrounding waters throughout the year.
In December, Helsinki experiences a low UV Index of 1, indicating minimal risk from sun exposure, with a burn time of 45 minutes. This trend of low UV levels continues from November and back to January, highlighting the city’s consistent chilly and overcast winter months where sun protection is largely unnecessary. As the year progresses into spring and summer, the UV Index sees a noticeable rise, peaking at 7 in June and July, categorizing those months as high exposure periods. As residents embrace the vibrant summer sun, awareness of the changing UV levels becomes crucial for safe outdoor activities. For detailed insights on how UV exposure varies throughout the year, check out Helsinki UV Index.
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In Helsinki, December brings a stark contrast to the sunnier months, with only 58 hours of daylight illuminating the city, marking a significant drop from the vibrant 154 hours in February and a notable dip compared to the subsequent spring months. The transition from the longest summer days, boasting 493 hours in June, to the dimmest winter months reveals a clear rhythm of light, as the city's residents prepare for the cozy embrace of winter. As the final month of the year unfolds, the sun's absence highlights the beauty of winter celebrations and the shimmering lights that adorn the city, transforming Helsinki into a magical wonderland despite the long nights. Though December's daylight is scarce, it sets the stage for a hopeful return as the hours gradually increase once more in January.
In December, the likelihood of sunny weather in Helsinki, Finland is relatively low, with a mere 14% chance of sunshine. This reflects a continuing decline from the 19% chance seen in both October and November, marking a transition into the cold, dark depths of winter. Notably, the chances of sunshine are significantly higher in earlier months, peaking in the summer with July offering a robust 56% sunny days. As the year progresses from the bright days of June and July through to the long, dim winters of December, it’s clear that Helsinki’s weather trend veers toward chill and cloud cover, leaving little room for sunlight during the final month of the year.
In December, Helsinki experiences its shortest days of the year, with only 5 hours of daylight. This stark contrast to the bright, endless summer nights illustrates the city’s dramatic seasonal shifts. As daylight gradually increases from January's 6 hours to February's 9, residents eagerly anticipate the return of the sun. March marks a notable transition with 11 hours, leading into April's 14 hours, a sign that spring is on the horizon. The trajectory peaks in June with an impressive 18 hours of daylight, before gradually descending again through the autumn months. This rhythmic cycle not only influences daily life but also nurtures a profound appreciation for the fleeting beauty of each sunlit hour in this northern gem.
As December arrives in Helsinki, the winds whisper a tranquil transition into winter, averaging 4.2 m/s (9 mph). This gentle breeze signals a slight increase from the previous month, maintaining a consistent rhythm after November's 4.4 m/s. The trend from October’s brisk 5.2 m/s suggests a gradual calming of the wind as the year draws to a close. Interestingly, the wind speed in December is comparable to earlier months like January and September, illustrating a sense of stability during the colder season. Embracing the cool air, Helsinki's residents are reminded of the city's resilient spirit as they navigate the serene, yet brisk December days.
Weather in Helsinki varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Helsinki, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of December and January, January tends to be colder, with minimum temperatures dropping to -23°C (-9°F) compared to December's minimum of -18°C (0°F). Both months see similar maximum temperatures, with January peaking at 8°C (46°F) and December at 7°C (44°F). While December experiences slightly more precipitation at 73 mm (2.9 in) over 15 days, January has less precipitation at 55 mm (2.2 in) over just 11 days. Additionally, January has a bit higher humidity, reaching 97% compared to December's 95%. For more detailed information, you can check Helsinki weather in January.
December and February weather in the region exhibit notable similarities and differences. In December, temperatures exhibit a milder range, with minimums around -18°C (0°F) and maximums reaching 7°C (44°F), resulting in an average temperature of -1°C (31°F). This month experiences higher precipitation levels at 73 mm (2.9 in) over about 15 days, contributing to the frequent dampness felt with a humidity level of 95%. In contrast, February tends to be colder, with minimum temperatures dropping to -23°C (-8°F) and a slightly lower average of -3°C (26°F). Precipitation decreases to 48 mm (1.9 in) over 10 days, yet the humidity remains constant at 95%. For more detailed insights about February weather, you can check Helsinki weather in February.
In December, temperatures in Helsinki range from a minimum of -18°C (0°F) to a maximum of 7°C (44°F), with an average of -1°C (31°F). The month experiences about 73 mm (2.9 in) of precipitation over 15 days, accompanied by high humidity at 95%. In contrast, March sees slightly colder conditions, with minimum temperatures dropping to -22°C (-7°F), while the maximum reaches 10°C (51°F) and averages the same -1°C (31°F). Precipitation decreases to 52 mm (2.0 in) over 12 days, and humidity is slightly lower at 93%. For a more detailed comparison, you can check Helsinki weather in March.
The weather in December is considerably colder than in April, with average temperatures hovering around -1°C (31°F), while April enjoys a milder average of 4°C (39°F). December experiences harsher conditions, with minimum temperatures dropping to -18°C (0°F) and maximums reaching only 7°C (44°F). In contrast, April sees minimums of -12°C (10°F) and maximums that can reach up to 19°C (67°F). Precipitation is relatively higher in December, occurring on 15 days with a total of 73 mm (2.9 in), compared to April's 48 mm (1.9 in) over just 9 days. Additionally, December is more humid at 95%, while April has a more comfortable 86%. For more details, check Helsinki weather in April.
December and May present contrasting weather experiences. In December, temperatures can plummet to a minimum of -18°C (0°F), with an average around -1°C (31°F) and maximum reaching only 7°C (44°F). This month is characterized by high humidity at 95% and frequent precipitation, occurring on 15 days and totaling 73 mm (2.9 inches). In stark contrast, May sees a milder climate with temperatures ranging from a minimum of -3°C (27°F) to an average of 10°C (50°F) and soaring to a maximum of 27°C (80°F). Precipitation is lighter, totaling 56 mm (2.2 inches) over just 10 days, and humidity drops to 75%. To explore more about May weather, you can visit Helsinki weather in May.
December and June present stark contrasts in weather. In December, temperatures can plummet to a minimum of -18°C (0°F), with an average of -1°C (31°F) and a maximum reaching 7°C (44°F). This month also experiences high humidity at 95% and considerable precipitation, averaging 73 mm (2.9 in) over 15 days. In contrast, June brings a much milder climate, with temperatures ranging from a minimum of 3°C (38°F) to a maximum of 30°C (86°F) and an average of 16°C (62°F). The humidity is significantly lower at 75%, and precipitation is also reduced to 61 mm (2.4 in) over just 10 days. For more details on June weather, check out Helsinki weather in June.
December and July present starkly contrasting weather conditions. In December, temperatures range from a frigid -18°C (0°F) to a maximum of 7°C (44°F), with an average around -1°C (31°F), creating a winter landscape. The month experiences a high level of humidity at 95% and sees about 73 mm (2.9 in) of precipitation over 15 days. In contrast, July brings a much milder climate, with temperatures ranging from a minimum of 8°C (46°F) to a sweltering maximum of 32°C (90°F), resulting in an average temperature of 18°C (65°F). While July has slightly higher precipitation at 91 mm (3.6 in) over 13 days, the humidity is notably lower at 80%. For a closer look at the warm summer season, check out Helsinki weather in July.
December and August showcase a stark contrast in weather conditions. In December, temperatures can plummet to a minimum of -18°C (0°F), with an average of -1°C (31°F) and a maximum reaching 7°C (44°F). The month is characterized by high humidity levels at 95%, accompanied by 73 mm (2.9 in) of precipitation over 15 days. In comparison, August enjoys milder temperatures, with a minimum of 7°C (45°F), an average of 17°C (62°F), and a maximum of 29°C (84°F). Precipitation is slightly higher at 83 mm (3.3 in) over just 13 days, but humidity is lower at 83%. This highlights a significant shift from the chilly, damp winter of December to the warm, humid days of August. For more details, you can refer to Helsinki weather in August.
When comparing the weather in December and September, notable differences emerge. December is characterized by much colder temperatures, with average highs barely reaching 7°C (44°F) and lows dropping to -18°C (0°F). In contrast, September offers a milder climate, boasting average highs of 23°C (73°F) and lows of -1°C (31°F). Both months experience similar amounts of precipitation, with December receiving 73 mm (2.9 in) over 15 days and September slightly more at 76 mm (3.0 in) across 13 days. Additionally, humidity levels are higher in December at 95%, compared to 90% in September, contributing to a chillier feel during the winter month. For more details, you can check out Helsinki weather in September.
When comparing the weather in December and October, significant differences emerge. December experiences much colder temperatures, with a minimum of -18°C (0°F) and an average of -1°C (31°F), while October offers a milder range, with a minimum of -4°C (25°F) and an average of 7°C (45°F). Additionally, October enjoys higher maximum temperatures, reaching up to 16°C (62°F), compared to December's 7°C (44°F). Both months see considerable precipitation, with October receiving 89 mm (3.5 in) over 17 days, while December sees slightly less—73 mm (2.9 in) over 15 days. Humidity remains high in both months, with December at 95% and October at 93%. For a closer look at October's climate, you can check Helsinki weather in October.
December weather in Helsinki is notably colder than in November, with average temperatures dropping to around -1°C (31°F) compared to November's milder average of 3°C (38°F). The minimum temperatures in December can plummet to -18°C (0°F), creating a stark contrast to November's minimum of -7°C (19°F). Additionally, December experiences slightly more precipitation at 73 mm (2.9 in) over 15 days, compared to November's 62 mm (2.5 in) over 13 days. Humidity remains high in both months, with December at 95% and November at 94%. For a detailed view of November's weather, you can visit Helsinki weather in November.
As December wraps Helsinki in its winter embrace, the weather takes a dramatic turn compared to the milder fall months. With temperatures dipping significantly, the city experiences an average chill that can plunge as low as -18°C (0°F), creating a frosty atmosphere that contrasts sharply with earlier weeks. Increased humidity levels, often reaching up to 95%, accompanied by nearly half the month seeing precipitation, further illustrate December's distinctive climate. Snow can blanket the city, transforming its landscape into a winter wonderland that invites holiday cheer. For a deeper look into how December fits into Helsinki's annual climate patterns, explore Helsinki Climate.