Grenay has warmer summer afternoons than 72% of mainland French towns
On a normal January night the air cools to about 1.1°C. Rain is plentiful here, more than falls on 72% of mainland French towns. A year here swings 26°C from midwinter lows to midsummer highs. Plan for rain on about 104 days a year, the days with 1 mm or more.
These are the figures of Météo-France’s Lyon-Saint-Exupery station, 6.8 km north.
A year in Grenay at a glance
Each month’s typical high and low in °C, at the Lyon-Saint-Exupery station.
What a year in Grenay feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Lyon-Saint-Exupery.
About 863 mm of rain a year
October is the wettest month and February the driest. About 26 days a year bring 10 mm or more. 78th wettest of 110 towns of 2,500+ in Isère.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Lyon-Saint-Exupery
43 frosts and 76 days of 25°C a year
On about 43 nights a year the air drops to 0°C or below, and on about 7 days it stays below freezing all day. About 76 days a year reach 25°C, and 26 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Lyon-Saint-Exupery: 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 Lyon-Saint-Exupery
Lyon-Saint-Exupery is 6.8 km north of Grenay. Every figure on this page is the station’s, not a measurement in Grenay itself.
| Station (Météo-France number) | Lyon-Saint-Exupery (69299001) |
| Distance from the town | 6.8 km north |
| Station altitude | 235 m |
| Town altitude (its center) | 298 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 Grenay 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 Isère.
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 |
|---|---|---|---|---|
| Grenay | Lyon-Saint-Exupery | 27.5°C | 1.1°C | 863 mm |
| Saint-Laurent-de-Mure 3.2 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
| Heyrieux 4.1 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
| Satolas-et-Bonce 4.6 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
| Saint-Quentin-Fallavier 4.7 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
| Saint-Bonnet-de-Mure 5.1 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
| Saint-Pierre-de-Chandieu 5.7 km | same station | 27.5°C about the same | 1.1°C about the same | 863 mm |
Grenay weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Lyon-Saint-Exupery station.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 6.6°C | 1.1°C | 3.9°C | 55 mm | 73 |
| February | 8.4°C | 1.4°C | 4.9°C | 47 mm | 99 |
| March | 13.4°C | 4.3°C | 8.8°C | 54 mm | 168 |
| April | 16.9°C | 7.3°C | 12.1°C | 72 mm | 183 |
| May | 20.9°C | 11.2°C | 16.1°C | 83 mm | 217 |
| June | 25.0°C | 14.8°C | 19.9°C | 71 mm | 252 |
| July | 27.5°C | 16.7°C | 22.1°C | 67 mm | 279 |
| August | 27.3°C | 16.5°C | 21.9°C | 71 mm | 247 |
| September | 22.5°C | 12.8°C | 17.7°C | 87 mm | 186 |
| October | 17.3°C | 9.6°C | 13.5°C | 101 mm | 124 |
| November | 11.0°C | 4.8°C | 7.9°C | 92 mm | 72 |
| December | 7.2°C | 1.9°C | 4.6°C | 63 mm | 50 |
| Year | 17.0°C | 8.5°C | 12.8°C | 863 mm | 1,947 |
Where Grenay’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Lyon-Saint-Exupery, 6.8 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, Lyon-Saint-Exupery, 6.8 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 Isère.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Grenay’s climate
How warm does Grenay get in summer?
July is the warmest month, with average highs of 27.5°C. About 76 days a year reach 25°C, more than 69% of mainland French towns, and about 26 reach 30°C.
How cold does Grenay get in winter?
January nights average 1.1°C. The air drops to 0°C or below on about 43 nights a year, and about 7 days a year stay below freezing all day.
How much rain does Grenay get?
About 863 mm a year, more than 72% of mainland French towns. October is the wettest month (101 mm) and February the driest (47 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Lyon-Saint-Exupery (6.8 km away), averages 1,947 hours of sunshine a year.
Are these figures for Grenay itself?
No: they are the normals of the Météo-France station matched to Grenay, Lyon-Saint-Exupery, 6.8 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 LYON-ST EXUPERY, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Grenay →
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.