Fewer days reach 25 degrees in Grumesnil than in 79% of mainland French towns
The coldest hours of a January night bottom out at 1.5°C on average. Expect the heaviest rain in December and the lightest in September. Frosty nights outnumber those of 70% of mainland French towns. Homes need heating from November to April, the months averaging under 10°C.
Figures from Météo-France’s Jaméricourt station, 37 km south: at that distance, read them as the area’s climate rather than the town’s.
A year in Grumesnil at a glance
Each month’s typical high and low in °C, at the Jaméricourt station.
What a year in Grumesnil feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Jaméricourt.
About 696 mm of rain a year
December is the wettest month and September the driest. About 18 days a year bring 10 mm or more. 77th wettest of 76 towns of 2,500+ in Seine-Maritime.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Beauvais-Tillé
A frosty town: 51 frosts and 42 days of 25°C a year
On about 51 nights a year the air drops to 0°C or below, and on about 5 days it stays below freezing all day. About 42 days a year reach 25°C, and 10 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Jaméricourt: a frost is a night of 0°C or below, a summer day (jour d’été) 25°C or more, a hot day (forte chaleur) 30°C or more.
The Météo-France station at Jaméricourt
Jaméricourt is 37 km south of Grumesnil. Every figure on this page is the station’s, not a measurement in Grumesnil itself.
| Station (Météo-France number) | Jaméricourt (60322001) |
| Distance from the town | 37 km south |
| Station altitude | 113 m |
| Town altitude (its center) | 224 m |
| Period | 1991–2020 |
| Nearest station of any kind | 6.8 km |
| Sunshine measured at | Beauvais-Tillé, 36 km away |
Grumesnil sits 111 m higher than the station. Air usually cools by about 0.65°C every 100 m, so expect Grumesnil to run about 0.7°C cooler than these figures.
TownRatings matches each commune to one station with at least 24 years of temperature and rain records: the nearest, counting every 100 m of height difference as 10 km, never across the sea.
How Grumesnil compares
Against the 4,385 towns of 2,500 or more in mainland France, each read from its own matched station. The dots are the other towns of 2,500+ in Seine-Maritime.
Nearby towns’ climate
The nearest towns of 2,500+ within 29 km, each with its own matched station.
| Town | Station | July high | January low | Rain a year |
|---|---|---|---|---|
| Grumesnil | Jaméricourt | 25.1°C | 1.5°C | 696 mm |
| Forges-les-Eaux 11 km | Rouen-Boos | 23.4°C 1.7°C cooler | 1.6°C about the same | 848 mm |
| Gournay-en-Bray 15 km | Étrépagny | 25.3°C about the same | 1.4°C about the same | 774 mm |
| Grandvilliers 19 km | Beauvais-Tillé | 24.4°C 0.7°C cooler | 1.4°C about the same | 656 mm |
| Neufchâtel-en-Bray 22 km | Oisemont | 23.2°C 1.9°C cooler | 1.9°C about the same | 801 mm |
| Buchy 25 km | Rouen-Boos | 23.4°C 1.7°C cooler | 1.6°C about the same | 848 mm |
| Crèvecœur-le-Grand 28 km | Beauvais-Tillé | 24.4°C 0.7°C cooler | 1.4°C about the same | 656 mm |
Grumesnil weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Jaméricourt station; sunshine at Beauvais-Tillé.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 6.7°C | 1.5°C | 4.1°C | 61 mm | 60 |
| February | 7.8°C | 1.4°C | 4.6°C | 50 mm | 79 |
| March | 11.6°C | 3.1°C | 7.3°C | 51 mm | 127 |
| April | 15.2°C | 4.5°C | 9.8°C | 49 mm | 179 |
| May | 18.6°C | 7.5°C | 13.1°C | 59 mm | 203 |
| June | 22.1°C | 10.3°C | 16.2°C | 54 mm | 209 |
| July | 25.1°C | 12.3°C | 18.7°C | 61 mm | 220 |
| August | 24.7°C | 12.4°C | 18.5°C | 56 mm | 208 |
| September | 20.8°C | 10.0°C | 15.4°C | 48 mm | 164 |
| October | 15.7°C | 7.7°C | 11.7°C | 63 mm | 112 |
| November | 10.4°C | 4.4°C | 7.4°C | 64 mm | 68 |
| December | 7.1°C | 2.0°C | 4.6°C | 79 mm | 55 |
| Year | 15.5°C | 6.4°C | 11.0°C | 696 mm | 1,682 |
Where Grumesnil’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Jaméricourt, 37 km away: statistics for 1991–2020.
- Which station: among stations with at least 24 of the 30 years of temperature and rain, the nearest to the commune’s population-weighted center, counting each 100 m of height difference as 10 km; mainland towns use mainland stations and each overseas département its own.
- Altitudes: the town’s from IGN’s RGE ALTI® at its population-weighted center; the station’s from Météo-France.
- Sunshine: the nearest station with at least 10 years of sunshine records, Beauvais-Tillé, 36 km away.
- Comparisons: every town of 2,500 or more in mainland France, read the same way; the dots are the towns of 2,500+ in Seine-Maritime.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Grumesnil’s climate
How warm does Grumesnil get in summer?
July is the warmest month, with average highs of 25.1°C. About 42 days a year reach 25°C, fewer than 79% of mainland French towns, and about 10 reach 30°C.
How cold does Grumesnil get in winter?
February nights average 1.4°C. The air drops to 0°C or below on about 51 nights a year, and about 5 days a year stay below freezing all day.
How much rain does Grumesnil get?
About 696 mm a year, less than 69% of mainland French towns. December is the wettest month (79 mm) and September the driest (48 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Beauvais-Tillé (36 km away), averages 1,682 hours of sunshine a year.
Are these figures for Grumesnil itself?
No: they are the normals of the Météo-France station matched to Grumesnil, Jaméricourt, 37 km away. France publishes its climate normals by station, not by commune; a valley, a hill or the sea can make a difference over a few kilometers.
Where do these figures come from?
Météo-France’s fiches climatologiques: 30-year averages (1991–2020) for each of its long-running stations, published as open data since 2024. They are normals, not a forecast.
Source: Météo-France, fiches climatologiques, 1991–2020 statistics (station JAMERICOURT, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Grumesnil →
Contains public sector information under the Licence Ouverte / Open Licence 2.0 (Etalab): INSEE, DGFiP, the Interior Ministry’s statistics service (SSMSI), the Ministry of Education (DEPP), the Health Ministry’s statistics service (DREES) and the Housing Ministry (Carte des loyers). Commune boundaries: IGN Admin Express.