Frost comes to Castex less often than to 91% of mainland French towns
January nights average 3.3°C, July afternoons 25.8°C, and a year brings 956 mm of rain. Rain is plentiful here, more than falls on 84% of mainland French towns. About 68 days a year reach 25°C, more than in 61% of mainland French towns. Figures from Météo-France’s Castelvieilh station, 14 km south-west.
A year in Castex at a glance
Each month’s typical high and low in °C, at the Castelvieilh station.
What a year in Castex feels like
Typical highs and lows by season and by month, from Météo-France’s 1991–2020 normals at Castelvieilh.
About 956 mm of rain a year
May is the wettest month and August the driest. About 33 days a year bring 10 mm or more. The wettest of 11 towns of 2,500+ in Gers.
Rain by month
Millimeters
Sunshine by month
Hours of sunshine at Campistrous
20 frosts and 68 days of 25°C a year
On about 20 nights a year the air drops to 0°C or below, and on about 1 days it stays below freezing all day. About 68 days a year reach 25°C, and 19 reach 30°C.
Day counts are Météo-France’s 1991–2020 normals at Castelvieilh: 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 Castelvieilh
Castelvieilh is 14 km south-west of Castex. Every figure on this page is the station’s, not a measurement in Castex itself.
| Station (Météo-France number) | Castelvieilh (65131001) |
| Distance from the town | 14 km south-west |
| Station altitude | 355 m |
| Town altitude (its center) | 309 m |
| Period | 1991–2020 |
| Nearest station of any kind | 3.9 km |
| Sunshine measured at | Campistrous, 28 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 Castex 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 Gers.
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 |
|---|---|---|---|---|
| Castex | Castelvieilh | 25.8°C | 3.3°C | 956 mm |
| Mirande 17 km | Mirande | 27.8°C 2°C warmer | 1.9°C 1.4°C colder | 819 mm |
| Vic-en-Bigorre 21 km | Vic-en-Bigorre | 26.6°C 0.8°C warmer | 0.8°C 2.5°C colder | 937 mm |
| Aureilhan 23 km | same station | 25.8°C about the same | 3.3°C about the same | 956 mm |
| Séméac 24 km | same station | 25.8°C about the same | 3.3°C about the same | 956 mm |
| Bordères-sur-l'Échez 25 km | Tarbes-Lourdes-Pyrenees | 25.2°C 0.6°C cooler | 1.1°C 2.2°C colder | 1,081 mm |
| Barbazan-Debat 25 km | Tarbes-Lourdes-Pyrenees | 25.2°C 0.6°C cooler | 1.1°C 2.2°C colder | 1,081 mm |
Castex weather by month
Average daily high and low, mean temperature and rain, 1991–2020, at the Castelvieilh station; sunshine at Campistrous.
| Month | High | Low | Mean | Rain | Sun (hours) |
|---|---|---|---|---|---|
| January | 10.0°C | 3.3°C | 6.6°C | 86 mm | 108 |
| February | 11.3°C | 3.5°C | 7.4°C | 65 mm | 134 |
| March | 14.4°C | 5.3°C | 9.9°C | 71 mm | 164 |
| April | 16.8°C | 7.4°C | 12.1°C | 102 mm | 168 |
| May | 20.3°C | 10.8°C | 15.5°C | 105 mm | 184 |
| June | 23.7°C | 13.9°C | 18.8°C | 80 mm | 202 |
| July | 25.8°C | 15.9°C | 20.9°C | 68 mm | 210 |
| August | 26.1°C | 16.3°C | 21.2°C | 60 mm | 204 |
| September | 23.0°C | 13.5°C | 18.3°C | 64 mm | 192 |
| October | 18.9°C | 10.5°C | 14.7°C | 73 mm | 160 |
| November | 13.2°C | 6.2°C | 9.7°C | 102 mm | 118 |
| December | 10.8°C | 4.1°C | 7.4°C | 81 mm | 117 |
| Year | 17.9°C | 9.2°C | 13.5°C | 956 mm | 1,960 |
Where Castex’s numbers come from
Averages over 30 years, not a forecast.
- Temperature, rain and day counts: Météo-France’s fiche climatologique for Castelvieilh, 14 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, Campistrous, 28 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 Gers.
Météo-France fiches climatologiques · IGN RGE ALTI®. Licence Ouverte 2.0.
Questions about Castex’s climate
How warm does Castex get in summer?
August is the warmest month, with average highs of 26.1°C. About 68 days a year reach 25°C, more than 61% of mainland French towns, and about 19 reach 30°C.
How cold does Castex get in winter?
January nights average 3.3°C. The air drops to 0°C or below on about 20 nights a year, and about 1 days a year stay below freezing all day.
How much rain does Castex get?
About 956 mm a year, more than 84% of mainland French towns. May is the wettest month (105 mm) and August the driest (60 mm).
How sunny is it?
The nearest Météo-France station that records sunshine, Campistrous (28 km away), averages 1,960 hours of sunshine a year.
Are these figures for Castex itself?
No: they are the normals of the Météo-France station matched to Castex, Castelvieilh, 14 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 CASTELVIEILH, edited 15/10/2026); altitude: IGN, RGE ALTI®. Licence Ouverte 2.0. Today’s forecast for Castex →
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.