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Hourly Forecast
Daylight Hours
07:43
Sunrise
19:45
Sunset
Moon
Waxing Gibbous
17:26
Moonrise
01:14
Moonset
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View stargazing scoreWeather in Cergy today, September 20, 2026
Cloud cover dominates in Cergy on September 20, 2026, keeping sunshine limited. Expect a grey, overcast feel rather than long bright spells.
Expect highs of 22°C and cooler readings close to 14°C. The air stays humid, with relative humidity between 72% and 83% and the peak around 23:00. Airflow remains manageable, reaching about 2.8 km/h around 17:00.
The afternoon keeps an overcast feel, as cloud reaches about 90% around 17:00. Outdoor plans may still want a flexible backup. Views remain open at about 16.1 km. Daylight runs from 07:43 to 19:45, lasting 12 hours 1 minutes of sunlight today.
Overall, Cergy on September 20, 2026 stays grey and muted, so outdoor plans may want a flexible backup even with a high near 22°C.
Frequently asked questions about weather in Cergy
How warm does it get in Cergy?
The warmest month in Cergy is July, with average high temperatures of 25°C. The average temperature during this period is around 20°C.
How cold does it get in Cergy?
The coldest month in Cergy is January, with average low temperatures of 2°C. The average temperature during this period is around 5°C.
What is the wettest time of year in Cergy?
The wettest month in Cergy is October, with an average of 79mm of precipitation.
What is the driest time of year in Cergy?
The driest month in Cergy is July, with an average of 49mm of precipitation.
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