The climate of Dunkirk (Dunkerque) is generally cool and wet, rainy and windy all year round, but especially in autumn and winter.
The city is located in the extreme north of France, a short distance from the border with Belgium.
The average temperature of the coldest month (January) is of 5 °C (41 °F), that of the warmest month (August) is of 18.4 °C (65 °F). Here are the average temperatures.
Dunkirk - Average temperatures
Min (°C)335710131516131064
Max (°C)771012161821211915118
Min (°F)373741455055596155504339
Max (°F)454550546164707066595246

Precipitation amounts to 700 millimeters (27.6 inches) per year: so, it is at an intermediate level. It ranges from 40 mm (1.6 in) in the driest month (February) to 80 mm (3.1 in) in the wettest (October). Here is the average precipitation.
Dunkirk - Average precipitation

The sea temperature ranges between 7 °C (45 °F) and 18 °C (64 °F). So, it never becomes warm for swimming. Here are the average sea temperatures.
Dunkirk - Sea temperature
Temp (°C)87791114161817151210
Temp (°F)464545485257616463595450


Best Time

The best time to visit Dunkirk runs from mid-May to mid-September, since it is the warmest and sunniest period of the year. Sometimes, nights can be cool or even a little cold even in these months, so it can be useful to bring a sweatshirt or sweater and a light jacket for the evening.