Weather without surprises: Onjon keeps close to the norm for mainland French towns
July afternoons reach 26.1°C on a typical day and January nights drop to 1.2°C; 734 mm of rain falls in a year. Wet weather is most frequent in October and least in February. By frosts alone, it ranks colder than 70% of mainland French towns. Frost greets about 50 mornings a year, so leave time to clear the car.
Figures from Météo-France’s Mathaux-Etape station, 15 km east.
A year in Onjon at a glance
Each month’s typical high and low in °C, at the Mathaux-Etape station.
What a year in Onjon feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Mathaux-Etape.
About 734 mm of rain a year
October is the wettest month and February the driest. About 20 days a year bring 10 mm or more. 4th wettest of 20 towns of 2,500+ in Aube.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Mathaux-Etape
A frosty town: 50 frosts and 56 days of 25°C a year
On about 50 nights a year the air drops to 0°C or below, and on about 6 days it stays below freezing all day. About 56 days a year reach 25°C, and 16 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Mathaux-Etape: 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 Mathaux-Etape
Mathaux-Etape is 15 km east of Onjon. Every figure on this page is the station’s, not a measurement in Onjon itself.
| Station (Météo-France number) | Mathaux-Etape (10228002) |
| Distance from the town | 15 km east |
| Station altitude | 145 m |
| Town altitude (its center) | 127 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 Onjon 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 Aube.
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 |
|---|---|---|---|---|
| Onjon | Mathaux-Etape | 26.1°C | 1.2°C | 734 mm |
| Pont-Sainte-Marie 16 km | Troyes-Barberey | 26.2°C about the same | 0.5°C 0.7°C colder | 645 mm |
| Saint-Parres-aux-Tertres 16 km | Troyes-Barberey | 26.2°C about the same | 0.5°C 0.7°C colder | 645 mm |
| Brienne-le-Château 18 km | same station | 26.1°C about the same | 1.2°C about the same | 734 mm |
| Arcis-sur-Aube 18 km | Dosnon | 26.2°C about the same | 0.4°C 0.8°C colder | 698 mm |
| Troyes 19 km | Troyes-Barberey | 26.2°C about the same | 0.5°C 0.7°C colder | 645 mm |
| Saint-Julien-les-Villas 19 km | Saint-Pouange | 27.0°C 0.9°C warmer | 0.6°C 0.6°C colder | 708 mm |
Onjon weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Mathaux-Etape station.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 6.4°C | 1.2°C | 3.8°C | 58 mm | 69 |
| February | 7.8°C | 1.2°C | 4.5°C | 52 mm | 97 |
| March | 12.0°C | 3.2°C | 7.6°C | 53 mm | 157 |
| April | 15.8°C | 5.2°C | 10.5°C | 54 mm | 207 |
| May | 19.6°C | 9.0°C | 14.3°C | 70 mm | 223 |
| June | 23.3°C | 12.1°C | 17.7°C | 57 mm | 248 |
| July | 26.1°C | 14.1°C | 20.1°C | 61 mm | 252 |
| August | 25.8°C | 14.0°C | 19.9°C | 61 mm | 223 |
| September | 21.4°C | 10.7°C | 16.0°C | 58 mm | 189 |
| October | 16.3°C | 8.1°C | 12.2°C | 72 mm | 127 |
| November | 10.3°C | 4.4°C | 7.4°C | 65 mm | 74 |
| December | 7.0°C | 2.0°C | 4.5°C | 72 mm | 64 |
| Year | 16.0°C | 7.1°C | 11.5°C | 734 mm | 1,930 |
Where Onjon’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Mathaux-Etape, 15 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, Mathaux-Etape, 15 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 Aube.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Onjon’s climate
How warm does Onjon get in summer?
July is the warmest month, with average highs of 26.1°C. About 56 days a year reach 25°C, fewer than 59% of mainland French towns, and about 16 reach 30°C.
How cold does Onjon get in winter?
January nights average 1.2°C. The air drops to 0°C or below on about 50 nights a year, and about 6 days a year stay below freezing all day.
How much rain does Onjon get?
About 734 mm a year, less than 58% of mainland French towns. October is the wettest month (72 mm) and February the driest (52 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Mathaux-Etape (15 km away), averages 1,930 hours of sunshine a year.
Are these figures for Onjon itself?
No: they are the normals of the Météo-France station matched to Onjon, Mathaux-Etape, 15 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 MATHAUX-ETAPE, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Onjon →
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.