Climate in 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.
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.



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.

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 - Climate data

In Dortmund, the average temperature of the coldest month (January) is of 3 °C (37.4 °F), that of the warmest month (July) is of 18.9 °C (66 °F). Here are the average temperatures.
Precipitation amounts to 795 millimeters (31.3 inches) per year: so, it is at an intermediate level. It ranges from 50 mm (2 in) in the driest month (February) to 85 mm (3.3 in) in the wettest one (July). Here is the average precipitation.
There are on average around 1590 sunshine hours per year. Here are the average hours of sunshine per day.

Dortmund - Weather by month

Based on the period 1991-2020

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