No extremes in Bais: its weather tracks the middle of mainland French towns
A typical January night drops to 2.5°C and a July afternoon reaches 25.4°C; 796 mm of rain falls in a year. Expect the heaviest rain in December and the lightest in July. None of the 99 towns of 2,500+ in Ille-et-Vilaine has warmer July afternoons. Comfortable outdoor weather lasts from May to October, with highs of 17–26°C.
Figures from Météo-France’s Cossé-le-Vivien station, 28 km east: at that distance, read them as the area’s climate rather than the town’s.
A year in Bais at a glance
Each month’s typical high and low in °C, at the Cossé-le-Vivien station.
What a year in Bais feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Cossé-le-Vivien.
About 796 mm of rain a year
December is the wettest month and July the driest. About 22 days a year bring 10 mm or more. 21st 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
43 frosts and 54 days of 25°C a year
On about 43 nights a year the air drops to 0°C or below, and on about 2 days it stays below freezing all day. About 54 days a year reach 25°C, and 13 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Cossé-le-Vivien: 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 Cossé-le-Vivien
Cossé-le-Vivien is 28 km east of Bais. Every figure on this page is the station’s, not a measurement in Bais itself.
| Station (Météo-France number) | Cossé-le-Vivien (53077001) |
| Distance from the town | 28 km east |
| Station altitude | 95 m |
| Town altitude (its center) | 70 m |
| Period | 1991–2020 |
| Nearest station of any kind | 9.3 km |
| Sunshine measured at | Rennes-Saint-Jacques, 33 km away |
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 Bais 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 |
|---|---|---|---|---|
| Bais | Cossé-le-Vivien | 25.4°C | 2.5°C | 796 mm |
| La Guerche-de-Bretagne 8.9 km | Soudan | 25.4°C about the same | 2.8°C about the same | 826 mm |
| Étrelles 9.2 km | same station | 25.4°C about the same | 2.5°C about the same | 796 mm |
| Piré-Chancé 9.6 km | Rennes-Saint-Jacques | 24.8°C 0.6°C cooler | 3.3°C 0.8°C milder | 691 mm |
| Argentré-du-Plessis 12 km | same station | 25.4°C about the same | 2.5°C about the same | 796 mm |
| Retiers 12 km | Soudan | 25.4°C about the same | 2.8°C about the same | 826 mm |
| Châteaubourg 13 km | Rennes-Saint-Jacques | 24.8°C 0.6°C cooler | 3.3°C 0.8°C milder | 691 mm |
Bais weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Cossé-le-Vivien station; sunshine at Rennes-Saint-Jacques.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 8.7°C | 2.5°C | 5.6°C | 78 mm | 68 |
| February | 9.9°C | 2.0°C | 6.0°C | 65 mm | 93 |
| March | 13.2°C | 3.7°C | 8.4°C | 57 mm | 134 |
| April | 16.2°C | 5.3°C | 10.7°C | 59 mm | 174 |
| May | 19.7°C | 8.6°C | 14.1°C | 59 mm | 202 |
| June | 23.1°C | 11.4°C | 17.3°C | 56 mm | 213 |
| July | 25.4°C | 12.9°C | 19.2°C | 48 mm | 220 |
| August | 25.6°C | 12.9°C | 19.2°C | 51 mm | 207 |
| September | 22.2°C | 10.4°C | 16.3°C | 65 mm | 181 |
| October | 17.2°C | 8.3°C | 12.7°C | 84 mm | 117 |
| November | 12.1°C | 4.9°C | 8.5°C | 83 mm | 84 |
| December | 9.1°C | 2.8°C | 5.9°C | 92 mm | 69 |
| Year | 16.9°C | 7.1°C | 12.0°C | 796 mm | 1,762 |
Where Bais’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Cossé-le-Vivien, 28 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, 33 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 Bais’s climate
How warm does Bais get in summer?
August is the warmest month, with average highs of 25.6°C. About 54 days a year reach 25°C, fewer than 64% of mainland French towns, and about 13 reach 30°C.
How cold does Bais get in winter?
February nights average 2.0°C. The air drops to 0°C or below on about 43 nights a year, and about 2 days a year stay below freezing all day.
How much rain does Bais get?
About 796 mm a year, more than 59% of mainland French towns. December is the wettest month (92 mm) and July the driest (48 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Rennes-Saint-Jacques (33 km away), averages 1,762 hours of sunshine a year.
Are these figures for Bais itself?
No: they are the normals of the Météo-France station matched to Bais, Cossé-le-Vivien, 28 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 COSSE-LE-VIVIEN, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Bais →
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.