The municipality benefits from a temperate oceanic climate, or an “oceanic climate with temperate summers” according to the Köppen classification. The average annual temperature is 10.9 °C, with precipitation of around 831 mm, almost evenly distributed throughout the year—slightly lower in summer (-10%) and somewhat higher from October to December (+10%). The prevailing winds, mainly from the west, are frequent on the plateau, influencing local weather conditions and contributing to cooler air.
According to the Normandy IPCC (GIEC Normand) (https://www.normandie.fr/giec-normand), the Mont-Saint-Aignan area is exposed to a “maritime climate” typical of north-western France: it is cool, humid, and rainy, and corresponds to the Pays de Caux, which is slightly cooler than the Cotentin region.
A rolling plateau…
Mont-Saint-Aignan, located near the city of Rouen in Normandy, stretches across a plateau overlooking the Seine Valley. The landscape is mainly composed of gentle hills and wooded areas, offering open viewpoints over the surrounding scenery. The urban fabric is relatively dense around the town center and residential districts, while natural spaces remain green and pleasant.
Présentation de la station du Mt St Aignan
The Mont-Saint-Aignan station is located on the University of Rouen campus, on the flat rooftop of Building 44, sheltered from any interference. The campus lies on a plateau overlooking the Seine Valley and is exposed to north-westerly winds. The data collected at the site are monthly and have been recorded since January 2021. Analyses are carried out at the GEOPS laboratory (Orsay).
The data collected at the Norville site are monthly and began in January 2021.
The analyses are carried out at the GEOPS laboratory (Orsay).
Latitude
Longitude
Altitude


































