Last updated: August 21, 2025
In Lahti, Finland, December brings a winter wonderland atmosphere characterized by a maximum temperature of 5°C (42°F) and an average low of -2°C (28°F). The month is marked by chilly nights, plunging as low as -20°C (-4°F), creating a striking contrast to the frosty days. With 71 mm (2.8 in) of total precipitation spread over 16 days, residents and visitors can expect a mix of snow and rain, adding to the seasonal charm. The air remains exceptionally crisp, with humidity levels reaching a high of 96%, ensuring that the essence of winter is felt throughout the city.
In December, Lahti, Finland embraces the depths of winter with temperatures that showcase the region's chilly charm. The month typically experiences a minimum of -20°C (-4°F) and an average of -2°C (28°F), reflecting a notable decline from the milder temperatures of November. With daytime highs barely reaching 5°C (42°F), December nights can feel particularly frigid, setting the scene for a snowy landscape and festive holiday atmosphere. This cold snap contributes to a stark contrast with the warmer summer months, emphasizing the beauty and resilience of Finnish winters, where the serene snow-covered scenery invites both adventure and introspection.
December in Lahti, Finland, showcases a notable shift towards winter with an average precipitation of 71 mm (2.8 in), marking it as one of the wetter months of the year. This increase in moisture, combined with 16 precipitation days, signals a transition into the snowier season, as the city braces for longer periods of wet weather. Compared to the preceding months, December’s rainfall is higher than November's 54 mm (2.1 in), indicating a trend towards increased precipitation as the year draws to a close. This consistent pattern suggests that while Lahti experiences mild rainfall in the fall, winter ushers in more persistent wet weather, setting the stage for a classic Finnish winter scene.
In December, Lahti, Finland experiences a high humidity level of 96%, reflecting a trend of moisture that characterizes the winter months. This value is moderately elevated compared to the preceding months, with humidity gradually decreasing from a peak of 98% in January to a low of 74% in June. The later months see a slight uptick as winter approaches, with November also recording 94% humidity. As the year draws to a close, residents can expect a consistent level of dampness, typical of the region's cold climate, making December a month where the chill is often accompanied by a thick, heavy air that emphasizes the beauty of a snow-covered landscape.
In December, Lahti, Finland experiences a UV Index of 1, categorizing it as a low exposure month. With a burn time of 45 minutes, residents and visitors can enjoy outdoor winter activities without significant risk from sun exposure. This consistent low UV Index, shared with the preceding months of January and November, highlights a trend of minimal solar intensity during the cold season. As the year transitions from the high summer months of June and July, where UV Index readings peak at 6 and 7, there is a noticeable drop in UV radiation in December. For those planning outdoor adventures this winter, it's comforting to know that the UV levels are manageable. For further details, visit Lahti UV Index.
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In December, Lahti, Finland, experiences a significant dip in sunshine, with only 38 hours of brilliant daylight gracing the month. This is starkly contrasted by the vibrant 429 hours seen in May and the sunniest month of the year, June, which boasts 475 hours. As the year progresses, there is a clear downward trend in daylight, with the longest months of sunshine falling between April and August, where residents bask in ample warmth and light. The winter months bring a somber shift, highlighted by November's 84 hours and January’s meager 44 hours. December's limited daylight acts as a poignant reminder of the stark beauty of Finnish winters, inviting cozy gatherings and reflective moments as the year comes to a close.
In Lahti, Finland, December marks a significant dip in sunny weather, with only a 10% chance of sunshine. This trend reflects the onset of winter, where the days grow shorter, and the clouds often dominate the sky. Notably, as the year progresses, the likelihood of sunny days increases, peaking in the summer months of July and June at 56% and 51%, respectively. However, December stands out as one of the year's gloomiest months, closely mirroring the previous months of November and October, both at 13%. As winter settles in, residents can expect those elusive sunny moments to be few and far between, highlighting the stark contrast between the vibrant, sunlit days of summer and the muted, overcast days of late autumn and early winter.
In December, Lahti, Finland experiences a notable dip in daylight, with only 5 hours of sun each day, marking the shortest period of light in the yearly cycle. This drop follows a gradual decline from the 19 hours enjoyed in June, through the cooler months where day length steadily diminishes. The transition from the vibrant 17 hours of daylight in May to December's limited sunshine starkly emphasizes the region's shift from the long, bright days of summer to the darker winter months. As the year closes, Lahti’s residents can expect to bundle up against the cold while savoring the brief daylight moments, a reminder of the balance between light and darkness that defines the Nordic winter.
As December rolls into Lahti, Finland, the average wind speed settles at 3.4 m/s (8 mph), showcasing a gentle yet persistent breeze that characterizes the transition into winter. Notably, this reflects a slight increase from November's 3.6 m/s, hinting at the robust winds that often accompany the cold season. Throughout the year, Lahti experiences a fluctuating wind pattern, with the calmest months falling during the summer, evidenced by June's mere 2.7 m/s. However, as the year progresses, wind speeds generally trend upward, particularly with peaks in October at 4.1 m/s. December's winds act as a subtle reminder of the increasing chill, blending harmoniously into the snowy landscape, while also foreshadowing the more intense gusts that winter will inevitably bring.
Weather in Lahti varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Lahti, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather is notably milder with average temperatures around -2°C (28°F) and a maximum of 5°C (42°F), while January sees a drop in minimum temperatures, plummeting to -25°C (-13°F) and an average of -4°C (25°F). December experiences more precipitation at 71 mm (2.8 in) over 16 days, compared to January's 49 mm (1.9 in) over just 11 days. Humidity levels are quite high in both months, peaking at 96% in December and slightly increasing to 98% in January. For a detailed look at January weather patterns, visit Lahti weather in January.
In December, the weather is generally milder compared to February, with average temperatures ranging from a minimum of -20°C (-4°F) to a maximum of 5°C (42°F) and an overall average of -2°C (28°F). The month experiences 71 mm (2.8 in) of precipitation spread over 16 days, maintaining a high humidity level of 96%. In contrast, February is notably colder, with temperatures dropping further to a minimum of -28°C (-17°F) and an average of -5°C (24°F), though it can peak at 7°C (46°F). Precipitation decreases to 45 mm (1.8 in) over 11 days, but humidity remains constant at 96%. For more detailed insights, you can check Lahti weather in February.
In December, the weather is chilly with temperatures ranging from a minimum of -20°C (-4°F) to a maximum of just 5°C (42°F), and the month experiences significant precipitation with 71 mm (2.8 in) over 16 days, accompanied by high humidity at 96%. In contrast, March sees slightly milder conditions, with temperatures ranging from -25°C (-13°F) to a maximum of 11°C (52°F). Precipitation during this month is lower, totaling 45 mm (1.8 in) across 11 days, while humidity remains relatively high at 93%. For a detailed look at what to expect, check out Lahti weather in March.
In December, Lahti experiences harsh winter conditions with temperatures ranging from a chilly -20°C (-4°F) at night to a maximum of just 5°C (42°F) during the day, along with high humidity levels of 96%. The month is characterized by significant precipitation, totaling 71 mm (2.8 in) over approximately 16 days, creating a snowscape common to the season.
In contrast, April brings a notable shift in weather patterns. Temperatures rise to a minimum of -11°C (12°F) and can reach up to 20°C (69°F), averaging around 3°C (38°F). Precipitation decreases to 48 mm (1.9 in) across about 11 days, and humidity drops to 87%. This transition marks the arrival of spring, as the milder temperatures and lighter conditions begin to thaw the winter landscape. For more details about April weather, visit Lahti weather in April.
December and May present stark contrasts in weather patterns and temperature ranges. In December, temperatures can plummet to a chilly minimum of -20°C (-4°F), with an average of -2°C (28°F) and highs reaching only 5°C (42°F). The month is characterized by significant precipitation, with rain or snow occurring on 16 days, resulting in a humidity level of 96%. In contrast, May offers a much milder climate, with minimum temperatures around -3°C (27°F) and average temperatures rising to 10°C (50°F), peaking at a warm 28°C (83°F). Precipitation decreases to 54 mm (2.1 in) over 10 days, and humidity drops to a more comfortable 75%. For more insights into the weather in May, you can visit Lahti weather in May.
In December, the weather is characterized by cold temperatures, with a minimum of -20°C (-4°F) and an average of -2°C (28°F), reaching a maximum of 5°C (42°F). The high humidity of 96% combined with 71 mm (2.8 in) of precipitation over 16 days creates a chilly and damp environment. In stark contrast, June brings a significant shift in climate, with temperatures ranging from a minimum of 2°C (35°F) to an enjoyable average of 16°C (61°F), peaking at 31°C (87°F). The month experiences a lighter precipitation of 63 mm (2.5 in) over 11 days and a lower humidity of 74%, resulting in a pleasant and more comfortable atmosphere. For a detailed overview of Lahti's June weather, you can visit Lahti weather in June.
December and July present strikingly contrasting weather patterns. In December, temperatures can plunge to a chilling minimum of -20°C (-4°F), with an average of -2°C (28°F) and highs reaching only 5°C (42°F). This month also sees frequent precipitation over 16 days, contributing to a high humidity level of 96%. In contrast, July offers a much milder climate, where temperatures range from a minimum of 7°C (45°F) to a pleasant average of 17°C (64°F), peaking at 30°C (87°F). Although it experiences slightly more precipitation at 77 mm (3.0 in) over only 12 days, humidity is lower at 80%. For more detailed information about July weather, you can visit Lahti weather in July.
December and August in Lahti present a striking contrast in weather. December is characterized by cold temperatures, with a minimum of -20°C (-4°F) and an average of -2°C (28°F), while August enjoys much milder conditions, boasting a minimum of 6°C (43°F) and an average of 16°C (61°F). Precipitation levels are somewhat similar, with December receiving 71 mm (2.8 in) across 16 days and August totaling 80 mm (3.2 in) over 13 days. Additionally, humidity is notably higher in December at 96%, compared to a more comfortable 85% in August. For a closer look at what to expect, check out Lahti weather in August.
December weather is characterized by significantly colder temperatures compared to September. While December experiences minimums plummeting to -20°C (-4°F) and an average of -2°C (28°F), September enjoys milder conditions with lows around -1°C (30°F) and an average of 11°C (52°F). Additionally, December has more precipitation spread over 16 days with 71 mm (2.8 in), whereas September sees slightly less precipitation at 62 mm (2.5 in) over 11 days. Humidity levels are also notably higher in December at 96%, compared to September's 90%, creating a distinct shift in the feel of the seasons. For more details on September's climate, you can visit Lahti weather in September.
In December, the weather turns significantly colder compared to October, with temperatures plunging to a minimum of -20°C (-4°F) and averaging around -2°C (28°F), while the maximum reaches only 5°C (42°F). In contrast, October presents a much milder climate, with temperatures ranging from a minimum of -5°C (23°F) to a pleasant maximum of 18°C (64°F) and an average of 6°C (43°F). Precipitation remains relatively similar between the two months, with December receiving 71 mm (2.8 in) over 16 days and October recording 78 mm (3.1 in) over 15 days. Humidity levels are also high in both months, though slightly higher in December at 96% compared to October's 94%. For more details on October's weather, you can refer to Lahti weather in October.
December weather tends to be colder and more humid than November, with average temperatures ranging from a minimum of -20°C (-4°F) to a maximum of 5°C (42°F). In contrast, November features milder temperatures, with a minimum of -10°C (14°F) and a maximum of 12°C (53°F). Additionally, December experiences more precipitation over more days, with 71 mm (2.8 in) falling across 16 days compared to November's 54 mm (2.1 in) over 11 days. This increase in precipitation, coupled with the colder temperatures and a higher humidity level of 96%, indicates that December is generally much chillier and wetter. For more information, check out Lahti weather in November.
As December settles over Lahti, the weather takes a striking turn compared to the milder months preceding it. With temperatures ranging from a brisk -20°C to a mild 5°C, the chilling cold and high humidity levels of 96% create an unmistakably wintry atmosphere. Over half of the month sees precipitation, with 16 days experiencing some form of rain or snow, contributing to the landscape's transformation into a winter wonderland. This stark contrast in weather patterns not only sets December apart but also invites both locals and visitors to embrace the season's unique charm and activities. For more details on how Lahti's climate unfolds throughout the year, check out Lahti Climate.