Winter nights in Guichen are milder than in 80% of mainland French towns
Peak summer warmth arrives in July, with afternoons near 24.8°C. By warm days alone, it ranks cooler than 77% of mainland French towns. Seasons differ by 22°C, from the coldest nights to the warmest afternoons. Frost greets about 30 mornings a year, so leave time to clear the car.
These are the figures of Météo-France’s Rennes-Saint-Jacques station, 12 km north.
A year in Guichen at a glance
Each month’s typical high and low in °C, at the Rennes-Saint-Jacques station.
What a year in Guichen feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Rennes-Saint-Jacques.
About 691 mm of rain a year
December is the wettest month and August the driest. About 19 days a year bring 10 mm or more. 50th wettest of 99 towns of 2,500+ in Ille-et-Vilaine.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Rennes-Saint-Jacques
30 frosts and 44 days of 25°C a year
On about 30 nights a year the air drops to 0°C or below, and on about under 1 days it stays below freezing all day. About 44 days a year reach 25°C, and 9 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Rennes-Saint-Jacques: 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 Rennes-Saint-Jacques
Rennes-Saint-Jacques is 12 km north of Guichen. Every figure on this page is the station’s, not a measurement in Guichen itself.
| Station (Météo-France number) | Rennes-Saint-Jacques (35281001) |
| Distance from the town | 12 km north |
| Station altitude | 36 m |
| Town altitude (its center) | 43 m |
| Period | 1991–2020 |
| Sunshine measured at | the same station |
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 Guichen 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 Ille-et-Vilaine.
Nearby towns’ climate
The nearest towns of 2,500+ within 29 km. Where a neighbor uses the same station its figures are the same: the differences you’d feel over a few kilometers aren’t in the normals.
| Town | Station | July high | January low | Rain a year |
|---|---|---|---|---|
| Guichen | Rennes-Saint-Jacques | 24.8°C | 3.3°C | 691 mm |
| Laillé 5.2 km | same station | 24.8°C about the same | 3.3°C about the same | 691 mm |
| Goven 5.7 km | same station | 24.8°C about the same | 3.3°C about the same | 691 mm |
| Bourg-des-Comptes 6.1 km | same station | 24.8°C about the same | 3.3°C about the same | 691 mm |
| Bruz 6.8 km | same station | 24.8°C about the same | 3.3°C about the same | 691 mm |
| Guignen 7.3 km | La Noë-Blanche | 25.0°C about the same | 3.2°C about the same | 781 mm |
| Pont-Péan 7.7 km | same station | 24.8°C about the same | 3.3°C about the same | 691 mm |
Guichen weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Rennes-Saint-Jacques station.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 9.2°C | 3.3°C | 6.2°C | 67 mm | 68 |
| February | 10.2°C | 2.9°C | 6.6°C | 52 mm | 93 |
| March | 13.2°C | 4.5°C | 8.8°C | 49 mm | 134 |
| April | 16.0°C | 6.0°C | 11.0°C | 51 mm | 174 |
| May | 19.3°C | 9.3°C | 14.3°C | 58 mm | 202 |
| June | 22.6°C | 12.1°C | 17.3°C | 51 mm | 213 |
| July | 24.8°C | 13.7°C | 19.2°C | 44 mm | 220 |
| August | 24.7°C | 13.8°C | 19.3°C | 44 mm | 207 |
| September | 21.9°C | 11.4°C | 16.6°C | 57 mm | 181 |
| October | 17.2°C | 9.3°C | 13.2°C | 73 mm | 117 |
| November | 12.5°C | 5.9°C | 9.2°C | 73 mm | 84 |
| December | 9.6°C | 3.6°C | 6.6°C | 73 mm | 69 |
| Year | 16.8°C | 8.0°C | 12.4°C | 691 mm | 1,762 |
Where Guichen’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Rennes-Saint-Jacques, 12 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, Rennes-Saint-Jacques, 12 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 Ille-et-Vilaine.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Guichen’s climate
How warm does Guichen get in summer?
July is the warmest month, with average highs of 24.8°C. About 44 days a year reach 25°C, fewer than 77% of mainland French towns, and about 9 reach 30°C.
How cold does Guichen get in winter?
February nights average 2.9°C. The air drops to 0°C or below on about 30 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Guichen get?
About 691 mm a year, less than 73% of mainland French towns. December is the wettest month (73 mm) and August the driest (44 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Rennes-Saint-Jacques (12 km away), averages 1,762 hours of sunshine a year.
Are these figures for Guichen itself?
No: they are the normals of the Météo-France station matched to Guichen, Rennes-Saint-Jacques, 12 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 RENNES-ST JACQUES, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Guichen →
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.