The week of 1 December 2025 - 7 December 2025 had an average daily temperature of 4 °C (39 °F) and a minimum (nighttime) temperature of 2 °C (36 °F). Both the daily and night temperatures in Lahti are above the long-term average, which is around -1 °C (30 °F) and -6 °C (21 °F) respectively. On average, the temperatures during various times of day (in local time) were recorded as: 7am 3 °C (37 °F), 10am 3 °C (37 °F), 1pm 4 °C (39 °F), 4pm 4 °C (39 °F), 7pm 3 °C (37 °F), 10pm 3 °C (37 °F).

During this week: 4 days without rain, 1 day with light rain and 2 days with moderate rain were observed. During the whole week, total of 19 mm (0.75 in) of precipitation was observed, which is above the long term average for Lahti, which is 12 mm (0.47 in). The average cloud coverage during the daytime (from dawn to dusk) was 100 %.

The wind's speed averaged 3.2 m/s. The most common wind direction(s) was South. The air pressure was 1007 hpa - 1023 hpa. The air in Lahti had an average humidity of 94 %.

During the daytime (from dawn to dusk), there were in average: 6 hours overcast skies and 1 hour rainy weather. The sunrise on average occurred at 09:07, and the sunset occurred at 15:08.

Weather overview

Lahti, located in Finland, experiences a moderately continental climate characterized by variable temperatures and precipitation throughout the year. Daytime temperatures can range from a chilly -4 °C (25 °F) in the frigid month of February to a warm 22 °C (71 °F) during the pleasant month of July. Nighttime temperatures follow a similar pattern, with the highest averages in July at 12 °C (54 °F), and the coldest nights in February reaching -10 °C (13 °F). April is notably the driest month, with an average of just 8 days of rainfall, while December is typically the wettest month with 13 days of rain. With this in mind, visitors should prepare accordingly for the season during which they plan to visit.

January weather

A decrease in daytime temperature is notable in Lahti, now averaging -4 °C (26 °F), and the night temperature has followed suit, dropping to -9 °C (15 °F). The peak wind speeds of the year can be observed this month, blowing at 3 m/s. A slight reduction in the number of rainy days begins this period, with an average of 12 days.

February weather

The lowest daytime temperature for the year is recorded at -4 °C (25 °F) in Lahti, with nighttime temperatures dropping to their lowest as well, at -10 °C (13 °F). Rainfall has decreased to 34 mm (1.33 in), and the number of rainy days has begun to decline, now at 10 days. Meanwhile, sunny hours start to increase, recorded at 2 hours.

March weather

March marks the onset of a rise in daytime temperatures, now at 1 °C (33 °F) in Lahti, with the trend continuing into the nighttime, where temperatures have risen to -6 °C (21 °F). A decline in the amount of rainy days persists, now at 9 days. An increase in sunny hours can be seen, now at 3 hours.

April weather

April sees a continued rise in daytime temperatures to 8 °C (46 °F) in Lahti and a significant increase in nighttime temperatures to -1 °C (30 °F). A seasonal low is reached in both the number of rainy days and rainfall amounts. The increment in sunny hours is noticeable, now averaging 5 hours.

May weather

Tourism in Lahti starts to pick up with the continued increase in daytime temperatures, now averaging 15 °C (60 °F), and nights warming to 5 °C (40 °F). Precipitation is on the rise, noted at 39 mm (1.54 in), while the lowest humidity levels can be observed during this time, averaging 67 %.

June weather

In June, daytime temperatures carry on their ascending trend, noted at 19 °C (67 °F) in Lahti, and night temperatures progress further, averaging 9 °C (49 °F). The tourist season is now evident. The number of rainy days begins to increase this month, but the highest count of sunny hours can still be enjoyed, averaging 9 hours.

July weather

Tourism in Lahti reaches its height along with the daytime temperature, reaching its zenith at 22 °C (71 °F), and nighttime temperatures also peaking at 12 °C (54 °F). Rainfall starts to climb from the previous month, noted at 73 mm (2.86 in), while the onset of a decrease in sunny hours begins.

August weather

August signals a pending shift in seasonality in Lahti, with a start of a decline in daytime temperatures, now at 19 °C (67 °F), and the same trend for nighttime temperatures is evident. The quantity of rainy days begins to increase, averaging 11 days, while the peak of rainfall for the year is recorded this month.

September weather

September sees a continuation of falling daytime temperatures, recorded at 13 °C (56 °F) in Lahti, with a similar trend in nighttime temperatures, now at 6 °C (43 °F). A reduction in the number of rainy days is observed, while a beginning decline in rainfall amounts is also noted. The amount of sunny hours starts to recede as well, now at 4 hours.

October weather

Daytime temperatures continue their downward trend, reaching 7 °C (45 °F) in Lahti, with nighttime temperatures also descending, now at 2 °C (36 °F). A gradual increase in rainfall volumes commences, now at 67 mm (2.62 in), and the number of rainy days starts to increase as well, noted at 11 days. A decline in sunny hours is observed, averaging 2 hours.

November weather

With November comes a likeness in the decline of daytime temperatures, now at 2 °C (35 °F), and nighttime temperatures steadily implunge as well, averaging -3 °C (27 °F). An ascent in the count of rainy days can be seen, now at 13 days, while the start of a decrease in rainfall is apparent. The maximum levels of humidity become evident, charting at 90 %.

December weather

December's continuation of dropping daytime temperatures, now at -2 °C (28 °F), and nighttime temperatures also descending in like manner. The highest amount of rainy days for the year is seen, now at 13 days. The day length hits its annual low point, while the least amount of sunny hours is recorded during this period.

How has the wind speed changed this month in Lahti?

Wind speeds in Lahti have reached their annual high, averaging 3 m/s for the month.

What is the trend in rainy days during this period?

The frequency of rainy days in Lahti has started to lessen, currently averaging 10 days this month.

What changes have occurred with respect to sunny hours this season?

Sunny hours in Lahti have experienced a surge, now averaging 3 hours each day.

How have daytime temperatures shifted recently in Lahti?

Daytime temperatures in Lahti have ascended to a mild 8 °C (46 °F) for April.

What is distinctive about humidity levels in May?

This month in Lahti features the lowest humidity levels of the year, averaging 67 %.

How do night temperatures in Lahti adjust during this time?

Night temperatures in June see a pleasant increase, now averaging 9 °C (49 °F) in Lahti.

With the peak of temperatures, how does tourism in Lahti fare?

With temperatures at their peak, especially a daytime high of 22 °C (71 °F), tourism in Lahti flourishes.

What significant weather shift begins to take place in August in Lahti?

A noticeable downturn in both daytime and nighttime temperatures begins to manifest in August.

What is the prevailing trend in rainy days and rainfall during September?

In September, Lahti experiences a declining trend in both rainy days, now at 11 days, and total rainfall amounts.

What changes are noted in the sunny hours in October in Lahti?

October marks a decrease in the duration of sunny periods, with an average of 2 hours of sunshine.

What is significant about humidity levels in November in Lahti?

November is characterized by some of the highest humidity levels of the year, peaking at 90 %.

How does the day length in December in Lahti compare regionally?

The day length in December in Lahti is at its shortest for the year, indicating the depth of winter.