Climate - Turku (Finland)

The climate of Turku is Baltic, that is, moderately continental, with cold winters, during which the average temperature is a few degrees below freezing, and mild to pleasantly warm summers.
The city is located in the south-west of Finland.
The white nights, when it doesn't get completely dark even at midnight, occur from 11 May to 3 August.
In winter, there can be cold spells of arctic origin. The coldest record is -35.2 °C (-31.4 °F) and was set in February 1966.
In summer, there can be short hot periods. The highest record is 32.4 °C (90.3 °F) and was set in July 2019.

Best Time

The best time to visit Turku is the summer, from June to August, since it is the mildest season. However, you must take into account some rainy days and a bit of cold at night.

Turku - Climate data

In Turku, the average temperature of the coldest month (February) is of -4.7 °C (23.5 °F), that of the warmest month (July) is of 17.7 °C (63.9 °F). Here are the average temperatures.
In Turku, precipitation amounts to 690 millimeters (27.2 inches) per year: so, it is at an intermediate level. It ranges from 35 mm (1.4 in) in the driest months (April, May) to 75 mm (3 in) in the wettest ones (July, August, October) Here is the average precipitation.
At Turku, the sea temperature ranges from 1.5 °C (35 °F) in February, March to 17.5 °C (64 °F) in August. Here are the average sea temperatures.
In Turku, there are on average around 1840 sunshine hours per year. Here are the average hours of sunshine per day.

Turku - Weather by month

Based on the period 1991-2020

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In January, the weather in Turku is usually very cold. The average temperature is of -3.3 °C (26 °F), with a minimum of -6 °C (21.2 °F) and a maximum of -0.6 °C (30.8 °F).
On the coldest nights of the month, the temperature usually drops to around -20 °C (-3.5 °F). However, it dropped to -29 °C (-20.2 °F) in January 2013.
On the warmest days of the month, the temperature usually reaches around 5.5 °C (42 °F). However, it reached 9 °C (48.2 °F) in January 2020.
Precipitation amounts to 60 mm (2.4 in), distributed over 11 days.
The day lasts on average 6 hours and 40 minutes. So the days are short.
There are on average 1.5 hours of sunshine per day. So, the sun shines 19% of the time.
The average humidity is 91%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 3 °C (37 °F). Therefore, the sea is very cold for swimming.

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In February, the coldest month of the year, the weather in Turku is usually very cold. The average temperature is of -4.7 °C (24 °F), with a minimum of -7.8 °C (18 °F) and a maximum of -1.7 °C (29 °F).
On the coldest nights of the month, the temperature usually drops to around -19.5 °C (-3 °F). However, it dropped to -28 °C (-18.4 °F) in February 2007.
On the warmest days of the month, the temperature usually reaches around 4.5 °C (40 °F). However, it reached 8 °C (46.4 °F) in February 2006.
Precipitation amounts to 40 mm (1.6 in), distributed over 9 days.
The day lasts on average 9 hours and 10 minutes.
There are on average 2.5 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 88%. Hence, the air is normally humid.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 1.5 °C (35 °F). Therefore, the sea is very cold for swimming.

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In March, the weather in Turku is usually very cold. The average temperature is of -1.1 °C (30 °F), with a minimum of -4.7 °C (23.6 °F) and a maximum of 2.4 °C (36.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -15 °C (5 °F). However, it dropped to -23 °C (-9.4 °F) in March 2013.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 9.5 °C (49 °F). However, it reached 16 °C (60.8 °F) in March 2007.
Precipitation amounts to 40 mm (1.6 in), distributed over 8 days.
The day lasts on average 11 hours and 55 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 36% of the time.
The average humidity is 80%. Hence, the air is normally humid.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 1.5 °C (34.5 °F). Therefore, the sea is very cold for swimming.

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In April, the weather in Turku is usually quite cold. The average temperature is of 4.5 °C (40 °F), with a minimum of -0.1 °C (31.8 °F) and a maximum of 9.2 °C (48.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -6.5 °C (20 °F). However, it dropped to -12 °C (10.4 °F) in April 2013.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 17.5 °C (63.5 °F). However, it reached 24.5 °C (76.1 °F) in April 1993.
Precipitation amounts to 35 mm (1.4 in), distributed over 8 days.
The day lasts on average 14 hours and 40 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 46% of the time.
The average humidity is 70%.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 2.5 °C (36.5 °F). Therefore, the sea is very cold for swimming.

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In May, the weather in Turku is usually mild. The average temperature is of 9.9 °C (50 °F), with a minimum of 4.6 °C (40.3 °F) and a maximum of 15.3 °C (59.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -2.5 °C (27.5 °F). However, it dropped to -6 °C (21.2 °F) in May 2007.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 24.5 °C (76 °F). However, it reached 30 °C (86 °F) in May 1995.
Precipitation amounts to 35 mm (1.4 in), distributed over 7 days.
The day lasts on average 17 hours and 25 minutes. So the days are very long.
There are on average 9 hours of sunshine per day. So, the sun shines 53% of the time.
The average humidity is 63%.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 5.5 °C (42.5 °F). Therefore, the sea is very cold for swimming.

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In June, the weather in Turku is usually mild. The average temperature is of 14.5 °C (58 °F), with a minimum of 9.4 °C (48.9 °F) and a maximum of 19.6 °C (67.3 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 2.5 °C (36.5 °F). However, it dropped to -2 °C (28.4 °F) in June 1991.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 26 °C (79 °F). However, it reached 31 °C (87.8 °F) in June 2011.
Precipitation amounts to 60 mm (2.4 in), distributed over 9 days.
The day lasts on average 18 hours and 55 minutes. So the days are very long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 9 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 67%.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 11 °C (52 °F). Therefore, the sea is very cold for swimming.

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In July, the warmest month of the year, the weather in Turku is usually very mild. The average temperature is of 17.7 °C (64 °F), with a minimum of 12.7 °C (54.9 °F) and a maximum of 22.6 °C (72.8 °F).
On the coldest nights of the month, the temperature usually drops to around 6 °C (43 °F). However, it dropped to 0 °C (32 °F) in July 2019.
On the warmest days of the month, the temperature usually reaches around 28.5 °C (83 °F). However, it reached 32.4 °C (90.3 °F) in July 2019.
Precipitation amounts to 75 mm (3 in), distributed over 9 days.
The day lasts on average 18 hours and 0 minutes. So the days are very long.
There are on average 9.5 hours of sunshine per day. So, the sun shines 51% of the time.
The average humidity is 70%.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 16 °C (61 °F). Therefore, the sea is cold for swimming.

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In August, the weather in Turku is usually very mild. The average temperature is of 16.5 °C (62 °F), with a minimum of 11.8 °C (53.2 °F) and a maximum of 21.2 °C (70.1 °F).
On the coldest nights of the month, the temperature usually drops to around 4 °C (39.5 °F). However, it dropped to 1.8 °C (35.2 °F) in August 2007.
On the warmest days of the month, the temperature usually reaches around 27 °C (81 °F). However, it reached 31.1 °C (88 °F) in August 2003.
Precipitation amounts to 75 mm (3 in), distributed over 10 days.
The day lasts on average 15 hours and 30 minutes. So the days are long.
There are on average 7.5 hours of sunshine per day. So, the sun shines 48% of the time.
The average humidity is 75%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).
The average sea temperature is of 17.5 °C (63.5 °F). Therefore, the sea is cold for swimming.

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In September, the weather in Turku is usually mild. The average temperature is of 11.4 °C (52 °F), with a minimum of 7.3 °C (45.2 °F) and a maximum of 15.4 °C (59.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -1 °C (30.5 °F). However, it dropped to -5 °C (23 °F) in September 2002.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 21.5 °C (70.5 °F). However, it reached 25 °C (77 °F) in September 2018.
Precipitation amounts to 60 mm (2.4 in), distributed over 9 days.
The day lasts on average 12 hours and 50 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 40% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 14.5 °C (58.5 °F). Therefore, the sea is very cold for swimming.

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In October, the weather in Turku is usually quite cold. The average temperature is of 5.7 °C (42 °F), with a minimum of 2.8 °C (37 °F) and a maximum of 8.5 °C (47.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -6.5 °C (20 °F). However, it dropped to -15 °C (5 °F) in October 1992.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 14.5 °C (58.5 °F). However, it reached 18.8 °C (65.8 °F) in October 2005.
Precipitation amounts to 75 mm (3 in), distributed over 11 days.
The day lasts on average 10 hours and 0 minutes.
There are on average 3 hours of sunshine per day. So, the sun shines 29% of the time.
The average humidity is 87%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 11 °C (51.5 °F). Therefore, the sea is very cold for swimming.

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In November, the weather in Turku is usually cold. The average temperature is of 0.8 °C (33 °F), with a minimum of -1.4 °C (29.5 °F) and a maximum of 3 °C (37.4 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -10 °C (13.5 °F). However, it dropped to -19.8 °C (-3.6 °F) in November 2010.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 9.5 °C (48.5 °F). However, it reached 14 °C (57.2 °F) in November 2020.
Precipitation amounts to 70 mm (2.8 in), distributed over 12 days.
The day lasts on average 7 hours and 25 minutes. So the days are short.
There are on average 1.5 hours of sunshine per day. So, the sun shines 17% of the time.
The average humidity is 91%. Hence, the air is normally humid.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 7.5 °C (45.5 °F). Therefore, the sea is very cold for swimming.

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In December, the weather in Turku is usually very cold. The average temperature is of -2.1 °C (28 °F), with a minimum of -4.6 °C (23.8 °F) and a maximum of 0.4 °C (32.6 °F).
On the coldest nights of the month, the temperature usually drops to around -14.5 °C (5.5 °F). However, it dropped to -27.5 °C (-17.5 °F) in December 1996.
On the warmest days of the month, the temperature usually reaches around 6.5 °C (44 °F). However, it reached 12 °C (53.6 °F) in December 1993.
Precipitation amounts to 70 mm (2.8 in), distributed over 12 days.
The day lasts on average 5 hours and 55 minutes. So the days are short. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There is an average of 1 hour of sunshine per day. So, the sun shines 15% of the time.
The average humidity is 91%. Hence, the air is normally humid.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 5 °C (41 °F). Therefore, the sea is very cold for swimming.