Photo: Maxime ✈ from Le François , Martinique · CC BY-SA 2.0Ice rarely forms: Châtillon sees fewer frosts than 89% of mainland French towns
Sunny July days climb to about 25.7°C. The rainiest month is May; the driest is February. Its yearly rainfall falls short of 88% of mainland French towns. Wet days, with 1 mm of rain or more, come about 109 times a year.
These are the figures of Météo-France’s Paris-Montsouris station, 4.2 km north-east.
A year in Châtillon at a glance
Each month’s typical high and low in °C, at the Paris-Montsouris station.
What a year in Châtillon feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Paris-Montsouris.
About 634 mm of rain a year
May is the wettest month and February the driest. About 16 days a year bring 10 mm or more. 22nd wettest of 35 towns of 2,500+ in Hauts-de-Seine.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Paris-Montsouris
21 frosts and 55 days of 25°C a year
On about 21 nights a year the air drops to 0°C or below, and on about 3 days it stays below freezing all day. About 55 days a year reach 25°C, and 14 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Paris-Montsouris: 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 Paris-Montsouris
Paris-Montsouris is 4.2 km north-east of Châtillon. Every figure on this page is the station’s, not a measurement in Châtillon itself.
| Station (Météo-France number) | Paris-Montsouris (75114001) |
| Distance from the town | 4.2 km north-east |
| Station altitude | 75 m |
| Town altitude (its center) | 95 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 Châtillon 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 Hauts-de-Seine.
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 |
|---|---|---|---|---|
| Châtillon | Paris-Montsouris | 25.7°C | 3.2°C | 634 mm |
| Fontenay-aux-Roses 1.6 km | same station | 25.7°C about the same | 3.2°C about the same | 634 mm |
| Malakoff 1.6 km | same station | 25.7°C about the same | 3.2°C about the same | 634 mm |
| Bagneux 1.9 km | same station | 25.7°C about the same | 3.2°C about the same | 634 mm |
| Vanves 2 km | Luxembourg | 26.5°C 0.8°C warmer | 3.4°C about the same | 667 mm |
| Clamart 2.2 km | same station | 25.7°C about the same | 3.2°C about the same | 634 mm |
| Montrouge 2.4 km | same station | 25.7°C about the same | 3.2°C about the same | 634 mm |
Châtillon weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Paris-Montsouris station.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 7.6°C | 3.2°C | 5.4°C | 48 mm | 59 |
| February | 8.8°C | 3.3°C | 6.0°C | 42 mm | 84 |
| March | 12.8°C | 5.6°C | 9.2°C | 45 mm | 135 |
| April | 16.6°C | 7.9°C | 12.2°C | 46 mm | 177 |
| May | 20.2°C | 11.1°C | 15.6°C | 69 mm | 201 |
| June | 23.4°C | 14.2°C | 18.8°C | 51 mm | 204 |
| July | 25.7°C | 16.2°C | 20.9°C | 59 mm | 222 |
| August | 25.6°C | 16.0°C | 20.8°C | 58 mm | 215 |
| September | 21.5°C | 13.0°C | 17.2°C | 45 mm | 175 |
| October | 16.5°C | 9.9°C | 13.2°C | 55 mm | 119 |
| November | 11.1°C | 6.2°C | 8.7°C | 54 mm | 70 |
| December | 8.0°C | 3.8°C | 5.9°C | 62 mm | 57 |
| Year | 16.5°C | 9.2°C | 12.8°C | 634 mm | 1,717 |
Where Châtillon’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Paris-Montsouris, 4.2 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, Paris-Montsouris, 4.2 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 Hauts-de-Seine.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Châtillon’s climate
How warm does Châtillon get in summer?
July is the warmest month, with average highs of 25.7°C. About 55 days a year reach 25°C, fewer than 61% of mainland French towns, and about 14 reach 30°C.
How cold does Châtillon get in winter?
January nights average 3.2°C. The air drops to 0°C or below on about 21 nights a year, and about 3 days a year stay below freezing all day.
How much rain does Châtillon get?
About 634 mm a year, less than 88% of mainland French towns. May is the wettest month (69 mm) and February the driest (42 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Paris-Montsouris (4.2 km away), averages 1,717 hours of sunshine a year.
Are these figures for Châtillon itself?
No: they are the normals of the Météo-France station matched to Châtillon, Paris-Montsouris, 4.2 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 PARIS-MONTSOURIS, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Châtillon →
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.