Climate - Dortmund (Germany)

In Dortmund, a German city located in the state of North Rhine-Westphalia, the climate is sub-oceanic. Winters are cold but not freezing, while summers are mild or pleasantly warm.
The Atlantic Ocean influences the climate, bringing clouds and rain for much of the year, and cold, unstable air from the North Sea. However, there can also be mild periods in winter, and warm to hot periods from late April to early October, because of air masses coming from the subtropical latitudes of the ocean.
The wind blows frequently and can be intense, especially from November to March.
Dortmund is the largest city in the Ruhr area, a conurbation that includes several cities, among which Bochum, Bottrop, Dortmund, Duisburg, Essen, Gelsenkirchen, Hagen, Hamm, Herne, Mülheim an der Ruhr, and Oberhausen.
The average temperature ranges from 3 °C (37.5 °F) in January to 19 °C (66 °F) in July. Here are the average temperatures.

Precipitation is relatively abundant, about 800 millimeters (31.5 inches) per year, but above all, it is frequent and well distributed over the seasons. However, the rainiest season (at least in quantity) is summer, and the least rainy season is spring. Rainfall often occurs in the form of short shower or drizzle, whereas during the summer, thunderstorms can break out in the afternoon. Here is the average precipitation.

Winter, from December to February, is cold: daytime temperatures are on average a few degrees above freezing (0 °C or 32 °F), while at night, they are around freezing. Wind and humidity often exacerbate the feeling of cold.
However, different weather situations can occur.
When the westerlies blow, the temperature can be quite mild and can reach 10/12 °C (50/54 °F), but there may be wind and rain.
On the contrary, when the city is reached by cold air masses from Russia, the temperature drops below freezing, for longer or shorter periods, even during the day. The temperature rarely drops below -15 °C (5 °F), however, it can do it during very cold periods, which used to be more frequent in the past. The coldest record is -27.8 °C (-18 °F) and was set in January 1942.
Snowfalls in Dortmund are quite frequent, though usually not abundant, and occur in the form of light snow, sometimes, however, snow can accumulate on the ground, and last for many days, if it occurs during cold waves.

Spring, from March to May, is an unstable season.
On the one hand, northwesterly currents can bring cold periods, so much so that in March, and sometimes until mid-April, it can still snow. In addition, some cold days, with highs around 10 °C (50 °F), can still occur in May, especially in the first half of the month.
On the other hand, southwesterly currents can bring very mild or quite warm periods, with highs above 20 °C (68 °F) in April and above 25 °C (77 °F) in May.

Summer, from June to August, is mild or pleasantly warm. The flow of Atlantic fronts does not cease even in this season. The wind blows quite often from the North Sea, which is not far, and rainfall is quite frequent as well.
However, there are pleasant periods, with daytime temperatures between 20 °C and 25 °C (68 and 77 °F), but also cooler periods, with daytime temperatures remaining below 20 °C (68 °F). At night, it can be a bit cold, since the temperature can drop below 10 °C (50 °F) even in July and August.
Sometimes, there can be hot days, during which the temperature can reach 30/32 °C (86/90 °F), while more rarely, it can even exceed 35 °C (95 °F). The highest record is 39 °C (102.2 °F) and was set in July 2019. In August 2020, the maximum temperature fluctuated between 30 and 35 °C (86 and 95 °F) for nine consecutive days.

Autumn, from September to November, is initially pleasant in September, and sometimes also in early October (although there is no shortage of rainfall), then it gradually becomes more cold, dull, wet and windy. The first night frosts usually occur in November, but sometimes also in October.



Dortmund does not get a lot of sun, especially from November to February, when the sun rarely shines. It goes a bit better from May to August, when the weather is variable, and between one disturbance and another, the sun can come out. In Dortmund, there are on average 1,590 hours of sunshine per year. Here are the average sunshine hours per day.

Best Time

The best time to visit Dortmund runs from mid-May to mid-September, since it's the mildest of the year. July and August are the warmest months. However, it's better to bring a sweatshirt or sweater, a light jacket, and an umbrella, for cool and rainy days.

Dortmund - Weather by month

Based on the period 1991-2020

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In January, the coldest month of the year, the weather in Dortmund is usually cold. The average temperature is of 3.0 °C (37 °F), with a minimum of 1 °C (33.8 °F) and a maximum of 5 °C (40.9 °F).
On the coldest nights of the month, the temperature usually drops to around -7.5 °C (18.5 °F). However, it dropped to -17 °C (1.4 °F) in January 1997.
On the warmest days of the month, the temperature usually reaches around 12 °C (53 °F). However, it reached 16 °C (60.8 °F) in January 1999.
Precipitation amounts to 65 mm (2.6 in), distributed over 12 days.
The day lasts on average 8 hours and 25 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 21% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 18 kph (11 mph).

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In February, the weather in Dortmund is usually cold. The average temperature is of 3.5 °C (38 °F), with a minimum of 1.1 °C (33.9 °F) and a maximum of 5.9 °C (42.7 °F).
On the coldest nights of the month, the temperature usually drops to around -6.5 °C (20 °F). However, it dropped to -15 °C (5 °F) in February 2012.
On the warmest days of the month, the temperature usually reaches around 13.5 °C (56 °F). However, it reached 20 °C (68 °F) in February 2019.
Precipitation amounts to 50 mm (2 in), distributed over 9 days.
The day lasts on average 10 hours and 0 minutes.
There are on average 2.5 hours of sunshine per day. So, the sun shines 26% of the time.
The average humidity is 77%. Hence, the air is normally humid.
The average wind speed is 18 kph (11 mph).

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In March, the weather in Dortmund is usually quite cold. The average temperature is of 6.4 °C (44 °F), with a minimum of 3.1 °C (37.6 °F) and a maximum of 9.7 °C (49.5 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -3.5 °C (26 °F). However, it dropped to -10 °C (14 °F) in March 2010.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 18 °C (64.5 °F). However, it reached 23 °C (73.4 °F) in March 1998.
Precipitation amounts to 55 mm (2.2 in), distributed over 13 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 4 hours of sunshine per day. So, the sun shines 34% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 17 kph (11 mph).

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In April, the weather in Dortmund is usually mild. The average temperature is of 10.1 °C (50 °F), with a minimum of 5.8 °C (42.4 °F) and a maximum of 14.4 °C (57.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -1 °C (30.5 °F). However, it dropped to -6 °C (21.2 °F) in April 1996.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 23 °C (73.5 °F). However, it reached 27 °C (80.6 °F) in April 2007.
Precipitation amounts to 60 mm (2.4 in), distributed over 10 days.
The day lasts on average 14 hours and 0 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 40% of the time.
The average humidity is 64%.
The average wind speed is 15 kph (9 mph).

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In May, the weather in Dortmund is usually mild. The average temperature is of 13.6 °C (56 °F), with a minimum of 9 °C (48.3 °F) and a maximum of 18.1 °C (64.6 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 2.5 °C (36 °F). However, it dropped to -1 °C (30.2 °F) in May 2011.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 26.5 °C (80 °F). However, it reached 32 °C (89.6 °F) in May 2005.
Precipitation amounts to 65 mm (2.6 in), distributed over 10 days.
The day lasts on average 15 hours and 40 minutes. So the days are long.
There are on average 6.5 hours of sunshine per day. So, the sun shines 41% of the time.
The average humidity is 65%.
The average wind speed is 14 kph (9 mph).

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In June, the weather in Dortmund is usually very mild. The average temperature is of 16.7 °C (62 °F), with a minimum of 12.2 °C (54 °F) and a maximum of 21.2 °C (70.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 7 °C (44 °F). However, it dropped to 3 °C (37.4 °F) in June 2009.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 30.5 °C (86.5 °F). However, it reached 36 °C (96.8 °F) in June 2019.
Precipitation amounts to 80 mm (3.1 in), distributed over 12 days.
The day lasts on average 16 hours and 35 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 6.5 hours of sunshine per day. So, the sun shines 40% of the time.
The average humidity is 66%.
The average wind speed is 13 kph (8 mph).

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In July, the warmest month of the year, the weather in Dortmund is usually warm. The average temperature is of 18.9 °C (66 °F), with a minimum of 14.3 °C (57.8 °F) and a maximum of 23.5 °C (74.3 °F).
On the coldest nights of the month, the temperature usually drops to around 9.5 °C (48.5 °F). However, it dropped to 6 °C (42.8 °F) in July 2015.
On the warmest days of the month, the temperature usually reaches around 32 °C (89.5 °F). However, it reached 39 °C (102.2 °F) in July 2019.
Precipitation amounts to 85 mm (3.3 in), distributed over 11 days.
The day lasts on average 16 hours and 5 minutes. So the days are long.
There are on average 6.5 hours of sunshine per day. So, the sun shines 42% of the time.
The average humidity is 65%.
The average wind speed is 14 kph (8 mph).

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In August, the weather in Dortmund is usually warm. The average temperature is of 18.7 °C (66 °F), with a minimum of 14.2 °C (57.6 °F) and a maximum of 23.2 °C (73.7 °F).
On the coldest nights of the month, the temperature usually drops to around 9 °C (48.5 °F). However, it dropped to 6 °C (42.8 °F) in August 2014.
On the warmest days of the month, the temperature usually reaches around 31.5 °C (89 °F). However, it reached 37 °C (98.6 °F) in August 2003.
Precipitation amounts to 75 mm (3 in), distributed over 9 days.
The day lasts on average 14 hours and 30 minutes. So the days are long.
There are on average 6 hours of sunshine per day. So, the sun shines 43% of the time.
The average humidity is 65%.
The average wind speed is 13 kph (8 mph).

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In September, the weather in Dortmund is usually very mild. The average temperature is of 15.2 °C (59 °F), with a minimum of 11.3 °C (52.3 °F) and a maximum of 19.1 °C (66.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 6 °C (42.5 °F). However, it dropped to 2 °C (35.6 °F) in September 2018.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 26.5 °C (80 °F). However, it reached 32 °C (89.6 °F) in September 2013.
Precipitation amounts to 65 mm (2.6 in), distributed over 11 days.
The day lasts on average 12 hours and 35 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 39% of the time.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 14 kph (8 mph).

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In October, the weather in Dortmund is usually mild. The average temperature is of 11.1 °C (52 °F), with a minimum of 8 °C (46.4 °F) and a maximum of 14.3 °C (57.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 1 °C (33.5 °F). However, it dropped to -5 °C (23 °F) in October 2003.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 21.5 °C (71 °F). However, it reached 28 °C (82.4 °F) in October 2018.
Precipitation amounts to 55 mm (2.2 in), distributed over 11 days.
The day lasts on average 10 hours and 35 minutes.
There are on average 3.5 hours of sunshine per day. So, the sun shines 34% of the time.
The average humidity is 77%. Hence, the air is normally humid.
The average wind speed is 15 kph (10 mph).

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In November, the weather in Dortmund is usually quite mild. The average temperature is of 6.9 °C (44 °F), with a minimum of 4.7 °C (40.4 °F) and a maximum of 9.1 °C (48.4 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -2 °C (28 °F). However, it dropped to -7 °C (19.4 °F) in November 1993.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 16 °C (60.5 °F). However, it reached 21 °C (69.8 °F) in November 2014.
Precipitation amounts to 70 mm (2.8 in), distributed over 12 days.
The day lasts on average 8 hours and 50 minutes.
There are on average 2 hours of sunshine per day. So, the sun shines 23% of the time.
The average humidity is 81%. Hence, the air is normally humid.
The average wind speed is 16 kph (10 mph).

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In December, the weather in Dortmund is usually cold. The average temperature is of 3.7 °C (39 °F), with a minimum of 1.9 °C (35.4 °F) and a maximum of 5.6 °C (42 °F).
On the coldest nights of the month, the temperature usually drops to around -6 °C (21 °F). However, it dropped to -15 °C (5 °F) in December 1996.
On the warmest days of the month, the temperature usually reaches around 12 °C (54 °F). However, it reached 16 °C (60.8 °F) in December 2019.
Precipitation amounts to 75 mm (3 in), distributed over 13 days.
The day lasts on average 7 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 are on average 1.5 hours of sunshine per day. So, the sun shines 19% of the time.
The average humidity is 83%. Hence, the air is normally humid.
The average wind speed is 18 kph (11 mph).