Weatheo

Grande-Synthe Weather by Month

Average temperatures, rainfall and humidity for Grande-Synthe, France, month by month, built from OpenWeather’s historical records. Use it to see what a typical Grande-Synthe month looks like before you travel — then check the live Grande-Synthe forecast for the days ahead.

Warmest month

July

24°C average high

Coolest month

January

2°C average low

Wettest month

January

69 mm of rain

Driest month

April

43 mm of rain

Average temperature and rainfall in Grande-Synthe by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

MonthAvg highAvg lowRecord low / highRainfallHumidityWind
January7°C2°C-13°C / 14°C
69 mm
86%16 km/h
February9°C3°C-8°C / 19°C
67 mm
81%18 km/h
March12°C4°C-13°C / 25°C
60 mm
74%16 km/h
April15°C6°C-2°C / 27°C
43 mm
67%15 km/h
May19°C9°C1°C / 32°C
47 mm
69%14 km/h
June23°C13°C6°C / 37°C
53 mm
69%13 km/h
July24°C14°C7°C / 41°C
60 mm
68%13 km/h
August24°C14°C7°C / 39°C
51 mm
69%12 km/h
September21°C12°C3°C / 34°C
54 mm
75%12 km/h
October16°C9°C-2°C / 27°C
67 mm
82%13 km/h
November11°C5°C-4°C / 19°C
68 mm
86%15 km/h
December8°C4°C-7°C / 21°C
63 mm
86%16 km/h

Best time to visit Grande-Synthe

The most comfortable time to visit Grande-Synthe is generally June to August, balancing mild daytime temperatures against the driest stretch of the year. The city has a moderate seasonal swing and rainfall is spread evenly across the months, totalling about 703 mm a year.

Travellers who prefer heat should aim for July, when highs average 24°C. January is the month to avoid if rain would spoil your plans — it averages 69 mm, roughly 2× the rainfall of the driest month (April).

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the Grande-Synthe forecast for what is happening now.

Weather across France right now