Martignat is among the wettest of mainland French towns: 1,568 mm of rain a year
Midsummer highs settle at about 25.4°C. The rainiest month is December; the driest is July. About 86 nights a year bring a frost, more than in 97% of mainland French towns. Keep the boiler serviced for the months from November to April, which average under 10°C.
Figures from Météo-France’s Cernon station, 21 km north.
A year in Martignat at a glance
Each month’s typical high and low in °C, at the Cernon station.
What a year in Martignat feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Cernon.
About 1,568 mm of rain a year
December is the wettest month and July the driest. About 56 days a year bring 10 mm or more. 5th wettest of 60 towns of 2,500+ in Ain.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Amberieu
A frosty town: 86 frosts and 57 days of 25°C a year
On about 86 nights a year the air drops to 0°C or below, and on about 9 days it stays below freezing all day. About 57 days a year reach 25°C, and 16 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Cernon: 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 Cernon
Cernon is 21 km north of Martignat. Every figure on this page is the station’s, not a measurement in Martignat itself.
| Station (Météo-France number) | Cernon (39086001) |
| Distance from the town | 21 km north |
| Station altitude | 500 m |
| Town altitude (its center) | 508 m |
| Period | 1991–2020 |
| Nearest station of any kind | 8.9 km |
| Sunshine measured at | Amberieu, 34 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 Martignat 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 Ain.
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 |
|---|---|---|---|---|
| Martignat | Cernon | 25.4°C | −1.5°C | 1,568 mm |
| Montréal-la-Cluse 4 km | Vieu | 24.7°C 0.7°C cooler | −2.8°C 1.3°C colder | 1,610 mm |
| Bellignat 4.7 km | same station | 25.4°C about the same | −1.5°C about the same | 1,568 mm |
| Oyonnax 6.2 km | same station | 25.4°C about the same | −1.5°C about the same | 1,568 mm |
| Nantua 6.4 km | Vieu | 24.7°C 0.7°C cooler | −2.8°C 1.3°C colder | 1,610 mm |
| Arbent 9.8 km | same station | 25.4°C about the same | −1.5°C about the same | 1,568 mm |
| Valserhône 19 km | Bellegarde | 27.5°C 2.1°C warmer | −1.7°C about the same | 1,185 mm |
Martignat weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Cernon station; sunshine at Amberieu.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 5.7°C | −1.5°C | 2.1°C | 136 mm | 68 |
| February | 7.4°C | −1.7°C | 2.9°C | 119 mm | 98 |
| March | 11.8°C | 0.9°C | 6.4°C | 120 mm | 170 |
| April | 15.5°C | 3.7°C | 9.6°C | 122 mm | 194 |
| May | 19.2°C | 7.8°C | 13.5°C | 138 mm | 220 |
| June | 23.1°C | 11.3°C | 17.2°C | 113 mm | 252 |
| July | 25.4°C | 13.1°C | 19.2°C | 112 mm | 288 |
| August | 25.3°C | 12.9°C | 19.1°C | 115 mm | 261 |
| September | 20.9°C | 9.5°C | 15.2°C | 116 mm | 189 |
| October | 16.3°C | 6.5°C | 11.4°C | 149 mm | 122 |
| November | 10.0°C | 2.1°C | 6.1°C | 162 mm | 73 |
| December | 6.1°C | −0.7°C | 2.7°C | 165 mm | 55 |
| Year | 15.6°C | 5.3°C | 10.4°C | 1,568 mm | 1,989 |
Where Martignat’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Cernon, 21 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, Amberieu, 34 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 Ain.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Martignat’s climate
How warm does Martignat get in summer?
July is the warmest month, with average highs of 25.4°C. About 57 days a year reach 25°C, fewer than 58% of mainland French towns, and about 16 reach 30°C.
How cold does Martignat get in winter?
February nights average −1.7°C. The air drops to 0°C or below on about 86 nights a year, and about 9 days a year stay below freezing all day.
How much rain does Martignat get?
About 1,568 mm a year, more than almost every mainland French town. December is the wettest month (165 mm) and July the driest (112 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Amberieu (34 km away), averages 1,989 hours of sunshine a year.
Are these figures for Martignat itself?
No: they are the normals of the Météo-France station matched to Martignat, Cernon, 21 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 CERNON, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Martignat →
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.