More rain falls on Jaillans than on 93% of mainland French towns: 1,136 mm a year
Midsummer highs settle at about 28.5°C. Temperatures cover 29°C across the year, low to high. Of the 40 towns of 2,500+ in Drôme, it has the coolest July afternoons. The heating season runs November to March: each of those months averages under 10°C.
Figures from Météo-France’s Saint-Jean-en-Roya station, 9.6 km east.
A year in Jaillans at a glance
Each month’s typical high and low in °C, at the Saint-Jean-en-Roya station.
What a year in Jaillans feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Saint-Jean-en-Roya.
About 1,136 mm of rain a year
October is the wettest month and February the driest. About 36 days a year bring 10 mm or more. The wettest of 40 towns of 2,500+ in Drôme.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Grenoble-Saint-Geoirs
A frosty town: 57 frosts and 89 days of 25°C a year
On about 57 nights a year the air drops to 0°C or below, and on about 5 days it stays below freezing all day. About 89 days a year reach 25°C, and 33 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Saint-Jean-en-Roya: 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 Saint-Jean-en-Roya
Saint-Jean-en-Roya is 9.6 km east of Jaillans. Every figure on this page is the station’s, not a measurement in Jaillans itself.
| Station (Météo-France number) | Saint-Jean-en-Roya (26307001) |
| Distance from the town | 9.6 km east |
| Station altitude | 308 m |
| Town altitude (its center) | 248 m |
| Period | 1991–2020 |
| Nearest station of any kind | 4.5 km |
| Sunshine measured at | Grenoble-Saint-Geoirs, 39 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 Jaillans 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 Drôme.
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 |
|---|---|---|---|---|
| Jaillans | Saint-Jean-en-Roya | 28.5°C | −0.1°C | 1,136 mm |
| Chatuzange-le-Goubet 7 km | Romans | 29.3°C 0.8°C warmer | 0.8°C 0.9°C milder | 877 mm |
| Saint-Jean-en-Royans 9.4 km | same station | 28.5°C about the same | −0.1°C about the same | 1,136 mm |
| Bourg-de-Péage 9.4 km | Romans | 29.3°C 0.8°C warmer | 0.8°C 0.9°C milder | 877 mm |
| Romans-sur-Isère 9.7 km | Romans | 29.3°C 0.8°C warmer | 0.8°C 0.9°C milder | 877 mm |
| Mours-Saint-Eusèbe 10 km | Romans | 29.3°C 0.8°C warmer | 0.8°C 0.9°C milder | 877 mm |
| Peyrins 12 km | Marsaz | 29.0°C 0.5°C warmer | 0.7°C 0.8°C milder | 883 mm |
Jaillans weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Saint-Jean-en-Roya station; sunshine at Grenoble-Saint-Geoirs.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 7.4°C | −0.1°C | 3.6°C | 75 mm | 91 |
| February | 9.2°C | 0.1°C | 4.6°C | 65 mm | 112 |
| March | 14.0°C | 2.8°C | 8.4°C | 74 mm | 173 |
| April | 17.5°C | 5.4°C | 11.5°C | 101 mm | 190 |
| May | 21.6°C | 9.2°C | 15.4°C | 114 mm | 221 |
| June | 25.7°C | 12.7°C | 19.2°C | 91 mm | 258 |
| July | 28.5°C | 14.6°C | 21.5°C | 89 mm | 292 |
| August | 28.1°C | 14.4°C | 21.3°C | 86 mm | 263 |
| September | 23.0°C | 11.1°C | 17.1°C | 116 mm | 199 |
| October | 18.0°C | 8.0°C | 13.0°C | 127 mm | 140 |
| November | 11.6°C | 3.6°C | 7.6°C | 124 mm | 91 |
| December | 7.8°C | 0.6°C | 4.2°C | 75 mm | 78 |
| Year | 17.7°C | 6.9°C | 12.3°C | 1,136 mm | 2,108 |
Where Jaillans’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Saint-Jean-en-Roya, 9.6 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, Grenoble-Saint-Geoirs, 39 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 Drôme.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Jaillans’s climate
How warm does Jaillans get in summer?
July is the warmest month, with average highs of 28.5°C. About 89 days a year reach 25°C, more than 79% of mainland French towns, and about 33 reach 30°C.
How cold does Jaillans get in winter?
January nights average −0.1°C. The air drops to 0°C or below on about 57 nights a year, and about 5 days a year stay below freezing all day.
How much rain does Jaillans get?
About 1,136 mm a year, more than 93% of mainland French towns. October is the wettest month (127 mm) and February the driest (65 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Grenoble-Saint-Geoirs (39 km away), averages 2,108 hours of sunshine a year.
Are these figures for Jaillans itself?
No: they are the normals of the Météo-France station matched to Jaillans, Saint-Jean-en-Roya, 9.6 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 ST-JEAN-EN-ROYA, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Jaillans →
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.