January Weather in Lahti, Finland

Last updated: August 21, 2025

January in Lahti, Finland presents a chilly panorama, with temperatures ranging from a frigid -25°C (-13°F) at night to a milder 7°C (46°F) during the day. The average temperature hovers around -4°C (25°F), setting the stage for a true winter experience. Residents and visitors can expect 49 mm (1.9 in) of precipitation over approximately 11 days, contributing to a high humidity level of 98% that adds a layer of crispness to the air. This month encapsulates the essence of Finnish winter, ideal for those looking to embrace snow-covered landscapes and frosty adventures.

January Temperature in Lahti

In January, Lahti, Finland, enters the heart of winter, showcasing a striking temperature range that captivates both locals and visitors alike. With a minimum of -25°C (-13°F) and an average temperature of -4°C (25°F), the month embraces the chill of the season, occasionally peaking at a maximum of 7°C (46°F). This cold snap marks a trend of gradually warming temperatures as the winter progresses; February dips even lower with a minimum of -28°C (-17°F), but averages only slightly colder than January at -5°C (24°F). It's a reminder that while winter's grip is firm, the impending promise of spring begins to loom, with temperatures slowly inching up in the following months. The fluctuation from bitter lows to more moderate highs paints a vivid picture of Lahti’s fierce yet beautiful winter landscape, setting the stage for the vibrant transformation that follows in the months ahead.

January Weather in Lahti: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Lahti, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Lahti, January 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).
JanFebMarAprMayJunJulAugSepOctNovDec252329385061636152433628
Data source: Temperature data for Lahti 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.

January Precipitation in Lahti

In January, Lahti, Finland, experiences an average precipitation of 49 mm (1.9 in), spread over approximately 11 days. This marks a steady start to the year, showcasing a slightly higher precipitation than in February and March, which both receive around 45 mm (1.8 in). Interestingly, the precipitation days remain consistent in these months, indicating that while January sets the tone for the winter, the fleeting chill leads right into a balanced springtime. As the season progresses through April and May, the rainfall gradually increases, peaking in the summer months of July and August with over 77 mm (3.0 in) and 80 mm (3.2 in) respectively. This trend reveals not only the moisture-laden shifts typical of a Finnish winter but also hints at how Lahti's climate transitions gracefully into a lush and vibrant summer, provided by higher precipitation levels in the warmer months.

January Precipitation Trends in Lahti

The chart displays monthly precipitation patterns in Lahti, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Lahti, January typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec494545485463778062785471
Data source: Precipitation data for January generated using information from the Copernicus Climate Change Service.
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January Humidity in Lahti

In January, Lahti experiences a remarkably high humidity level of 98%, making it one of the most moisture-laden months of the year. This peak in humidity begins a gradual decline leading into February, which sees a slight reduction to 96%, and continues to decrease through the spring months, dropping to 87% by April. As the weather warms into May, humidity levels significantly lower to 75%, creating a refreshing transition into summer. However, by July, humidity begins to rise once more, peaking again as it reaches 80% before stabilizing throughout the late summer and early autumn months. Overall, Lahti's humidity trends reflect a dynamic cycle that corresponds closely with the changing seasons, highlighting the region's characteristic dampness during winter and moderate levels in summer.

January Average Humidity in Lahti

This chart illustrates the average monthly humidity levels in Lahti, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Lahti is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec98%96%93%87%75%74%80%85%90%94%94%96%
Data source: Humidity data for January generated using information from the Copernicus Climate Change Service.

January UV Index in Lahti

In Lahti, Finland, the UV Index in January remains low at 1, indicating minimal risk of harm from unprotected sun exposure, with a burn time of 45 minutes. This pattern continues into February, with the UV Index unchanged, providing a consistent opportunity for outdoor activities without significant sunburn risk. However, as spring approaches, the UV Index rises to 3 in March and reaches 4 in April, marking a shift to moderate exposure levels that warrant more caution. By May, the index peaks at 5, reinforcing the need for protection as the days grow longer and sunnier. Through the summer months of June and July, UV levels soar to 6 and 7, respectively, representing high exposure risks with significantly reduced burn times of just 25 minutes. As autumn approaches, the index gradually lowers again, returning to low levels by November. This seasonal variability in UV levels reminds us to stay vigilant and adjust our sun protection strategies accordingly. For detailed information on the UV Index throughout the year, visit Lahti UV Index.

Maximum UV Index Levels in Lahti for January

The chart shows the monthly maximum UV Index (UVI) for Lahti in January, 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 January, the maximum UV index in Lahti typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec113456753211
Data source: Lahti January 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.

January Sunshine in Lahti

In Lahti, Finland, January marks the beginning of a gradual transition from the stark winter months toward the vibrant energy of spring and summer. With only 44 hours of sunshine, January stands in stark contrast to the sun-soaked months that follow. As February arrives, sunshine nearly triples to 136 hours, hinting at the shifting seasons ahead. March and April continue this upward trend, with hours soaring to 242 and 348 respectively, painting a picture of increasing warmth and brightness. By the time May rolls around, the city basks in 429 hours of sunlight, leading into the peak of summer where June and July shine brightly with 475 and 467 hours. Even as August begins to share its warmth, the days gradually shorten, making way for September’s 257 hours. Although the sun retreats once more in the fall, the joyous leap from January’s dimness to the summer’s radiance encapsulates the unique beauty of Lahti’s seasonal rhythm.

Monthly Sunshine Duration in Lahti: January Highlighted

The January sunshine duration represents the total number of hours Lahti experiences direct sunlight during the month of January, excluding cloudy or obstructed periods. This chart compares the sunshine duration of January with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec44h136h242h348h429h475h467h385h257h154h84h38h
Data source: Lahti January Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Lahti During January

In Lahti, Finland, the chance of enjoying a sunny day in January is a mere 3%, making it one of the gloomiest months of the year. As winter drags on, the likelihood of sun gradually increases, with February showing a slight rise to 13%. However, the true emergence of brighter days begins in March, where the chance jumps to 37%. As spring unfolds, April sees a further boost to 41%, providing a welcome transition towards sunnier months. By June and July, residents can bask in the summer sun, with probabilities soaring to 51% and 56%, respectively. This upward trend is a reminder that as the year advances, Lahti transforms into a brighter and more cheerful destination.

Percentage of Sunny Days in January in Lahti

The chart illustrates the percentage of sunny days in Lahti throughout the year, with January 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 Lahti experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec3%13%37%41%29%51%56%25%22%13%13%10%
Data source: Lahti January chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Lahti in January

In Lahti, Finland, January marks the beginning of a gradual awakening from the deep winter slumber, offering just 6 hours of daylight. As the month progresses toward spring, daylight increases significantly, with February bringing 9 hours and March reaching 11 hours. By April, the days stretch to 14 hours, ushering in the lush vitality of spring, which continues to blossom in May with 17 hours of sunlight. The peak of daylight is experienced in June at 19 hours, soaking the city in natural light. The trend begins to reverse post-June, as days gradually shorten; July enjoys 18 hours, while August sees a decline to 15 hours. September offers 12 hours, and as autumn deepens, daylight dwindles to 9 hours in October and further to 7 hours in November. December rounds out the year with a mere 5 hours of daylight, illustrating a striking seasonal cycle that captivates the rhythm of life in Lahti.

Average Daylight Hours in Lahti for January

The chart illustrates the variation in daylight duration in Lahti throughout the year, with January highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec6h 32m9h 1m11h 51m14h 44m17h 27m19h 4m18h 11m15h 39m12h 49m9h 58m7h 16m5h 40m
Data source: Lahti daylight hours, calculated by summing the hours between sunrise and sunset for each day.

January Winds in Lahti

In January, Lahti, Finland, experiences a gentle embrace of winter winds with an average speed of 3.1 m/s (7 mph). This relatively calm breeze sets the tone for the month, offering a peaceful contrast to the harsher elements of winter. As the seasons shift, February sees a slight decrease in wind speed, matching January's calm at 3.0 m/s. However, come March, the winds pick up with an increase to 3.8 m/s (8 mph), signaling the approach of spring and the beginning of a lively transition. The months that follow reveal a varied but consistent pattern; while April and May return to milder conditions of around 3.1 m/s, the winds strengthen again in August and October, reaching 3.6 m/s and 4.1 m/s respectively. Notably, the tempestuous gales of late summer and autumn underscore a shift in the seasonal dynamics after the tranquility of January, highlighting the ever-changing character of Lahti's atmosphere throughout the year.

Average January Wind Speed in Lahti

The chart displays monthly wind speed patterns in Lahti, with values for each month shown alongside January's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how January's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec3.1 m/s3.03.83.33.12.72.83.63.34.13.63.4
Data source: Lahti January wind data, generated using information from the Copernicus Climate Change Service.

How January Weather in Lahti Compares to Other Months

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

January and February exhibit similar temperatures and precipitation patterns, although February tends to be slightly colder. In January, the average temperature hovers around -4°C (25°F), with a minimum of -25°C (-13°F) and a maximum of 7°C (46°F). In contrast, February's average temperature dips slightly to -5°C (24°F), with a minimum of -28°C (-17°F), while the maximum remains the same at 7°C (46°F). Both months receive comparable precipitation, with January recording 49 mm (1.9 in) and February just slightly less at 45 mm (1.8 in), and both experience precipitation on about 11 days. Despite these similarities, February's humidity is marginally lower at 96%, compared to January's high of 98%. For more detailed information, visit Lahti weather in February.

In January, temperatures can plummet to a chilling minimum of -25°C (-13°F), with an average of -4°C (25°F) and a maximum of 7°C (46°F). The month is characterized by high humidity at 98% and receives about 49 mm (1.9 in) of precipitation over 11 days. In contrast, March sees a slight rise in temperatures, with minimums still around -25°C (-13°F), an average of -2°C (29°F), and a maximum of 11°C (52°F). Precipitation decreases slightly to 45 mm (1.8 in) over the same 11 days but features lower humidity at 93%. For a detailed weather overview, visit Lahti weather in March.

In January, the weather is notably colder, with temperatures ranging from a frigid -25°C (-13°F) to a mild 7°C (46°F), while the average temperature hovers around -4°C (25°F). The month experiences significant humidity at 98% and receives 49 mm (1.9 in) of precipitation over 11 days. In contrast, April brings a noticeable warming trend, with temperatures ranging from -11°C (12°F) to a pleasant 20°C (69°F), and an average temperature of 3°C (38°F). Although April sees similar precipitation levels of 48 mm (1.9 in) over the same number of days, the humidity decreases to 87%. For more detailed information on April's climate, visit Lahti weather in April.

January and May present a stark contrast in weather conditions. In January, temperatures can plunge as low as -25°C (-13°F) with an average of -4°C (25°F), making it the coldest month of the year. The high humidity of 98% coupled with 49 mm of precipitation over 11 days creates a cold and damp atmosphere. In comparison, May experiences much milder temperatures, with a minimum of -3°C (27°F) and a pleasant average of 10°C (50°F), peaking at a warm 28°C (83°F). Although May sees a slightly higher precipitation of 54 mm over 10 days, the lower humidity of 75% lends a more comfortable feeling to this spring month. For a more detailed look at May's weather, visit Lahti weather in May.

In January, the weather is characterized by frigid temperatures, with a minimum of -25°C (-13°F) and an average of -4°C (25°F), while the maximum reaches only 7°C (46°F). This month also sees high humidity levels at 98% and experiences 49 mm (1.9 in) of precipitation over 11 days. In stark contrast, June boasts much milder conditions, with temperatures ranging from a minimum of 2°C (35°F) to a maximum of 31°C (87°F), and an average of 16°C (61°F). Although June experiences slightly more precipitation at 63 mm (2.5 in), it still enjoys lower humidity at 74%. For a detailed look at the June weather in Lahti, visit Lahti weather in June.

In January, temperatures in Lahti plummet, with minimums reaching as low as -25°C (-13°F) and average highs around a chilly 7°C (46°F). The winter month sees significant humidity at 98%, with precipitation totaling 49 mm (1.9 in) over 11 days. In contrast, July brings a much milder climate, where the temperature ranges from a comfortable minimum of 7°C (45°F) to a maximum of 30°C (87°F) and an average around 17°C (64°F). While July experiences slightly more precipitation at 77 mm (3.0 in) over 12 days, the humidity drops to a more moderate 80%. For a closer look at the warm and vibrant summer weather, you can check out Lahti weather in July.

January and August present a stark contrast in weather conditions. In January, temperatures plummet to a chilling minimum of -25°C (-13°F), with an average of -4°C (25°F) and a maximum of 7°C (46°F). This month sees significant humidity, reaching 98%, along with moderate precipitation of 49 mm (1.9 in) over 11 days. In comparison, August brings a much warmer climate, featuring a minimum temperature of 6°C (43°F), an average of 16°C (61°F), and a maximum soaring to 31°C (87°F). Precipitation increases slightly to 80 mm (3.2 in) across 13 days, but the humidity is noticeably lower at 85%. For more detailed information on Lahti's August weather, visit Lahti weather in August.

In January, the weather in Lahti is quite frigid, with temperatures ranging from a chilling minimum of -25°C (-13°F) to an average of -4°C (25°F) and a maximum of 7°C (46°F). Despite the cold, the month sees a moderate level of precipitation at 49 mm (1.9 in) over about 11 days, contributing to a humidity level that hovers around a frosty 98%. In contrast, September offers a more temperate experience, with temperatures varying from a minimum of -1°C (30°F) to a pleasant average of 11°C (52°F) and reaching a maximum of 23°C (73°F). The precipitation increases slightly to 62 mm (2.5 in), also spread over 11 days, though the humidity eases to 90%. For those interested in the specifics of September weather, more information can be found at Lahti weather in September.

In January, the weather is significantly colder, with temperatures ranging from a bone-chilling -25°C (-13°F) to a maximum of 7°C (46°F) and an average of -4°C (25°F). The humidity is very high at 98%, and the month sees about 49 mm (1.9 in) of precipitation spread over 11 days.

In contrast, October brings milder conditions, with temperatures ranging from a minimum of -5°C (23°F) to a maximum of 18°C (64°F) and an average of 6°C (43°F). October also experiences higher precipitation, totaling 78 mm (3.1 in) over 15 days, while humidity remains slightly lower at 94%. For more specific insights into the weather in Lahti during October, visit Lahti weather in October.

When comparing the weather of January and November, a noticeable difference in temperature stands out. January experiences significantly colder temperatures, with averages around -4°C (25°F) and a minimum plunging to -25°C (-13°F), while November sees milder conditions with average temperatures around 2°C (36°F) and a minimum of -10°C (14°F). Both months have similar precipitation levels, with January receiving 49 mm (1.9 in) and November slightly higher at 54 mm (2.1 in), both typically experiencing precipitation on about 11 days. The humidity in January is slightly higher at 98% compared to 94% in November, contributing to a more frigid and damp feel during the early part of the year. For more specific details on November weather, you can visit Lahti weather in November.

January and December both experience frigid temperatures, but January is generally colder, with average temperatures around -4°C (25°F) compared to December's average of -2°C (28°F). The minimum temperatures in January can plummet to -25°C (-13°F), slightly colder than December's -20°C (-4°F). Additionally, January sees less precipitation, with 49 mm (1.9 in) over 11 days, while December has higher precipitation levels of 71 mm (2.8 in) across 16 days, which can contribute to a heavier snowpack. Humidity remains high in both months, with January at 98% and December at 96%. For a more detailed look at December weather in Lahti, visit Lahti weather in December.

Compare Lahti's Climate with Cities Worldwide

Conclusion: What to Expect From January Weather in Lahti

As January grips Lahti, the contrast with other months becomes apparent. The frigid temperatures, often diving to bone-chilling lows, make it one of the coldest periods of the year, while the average -4°C casts a stark difference from the milder late autumn and early spring temperatures. With high humidity levels reaching an impressive 98% and nearly half of the month experiencing precipitation, this month is characterized by a damp chill that pervades the air. January's unique weather dynamics create a beautiful but brisk winter landscape, offering a stark reminder of Finland's seasonal transformations. For a deeper look into Lahti's climatic patterns, explore Lahti Climate.