Nantes weather by month
Nantes runs from about 6°C in January to 20°C in August, with October the wettest month at 165 mm.
warmest month
August
20°C
coolest month
January
6°C
wettest month
October
165 mm
worst air month
December
12 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 6°C | 116 mm | 175 h | 9 |
| February | 10°C | 134 mm | 113 h | 7 |
| March | 9°C | 109 mm | 221 h | 11 |
| April | 11°C | 93 mm | 267 h | 7 |
| May | 14°C | 100 mm | 307 h | 7 |
| June | 17°C | 77 mm | 355 h | 7 |
| July | 19°C | 86 mm | 321 h | 5 |
| August | 20°C | 56 mm | 335 h | 7 |
| September | 15°C | 107 mm | 252 h | 6 |
| October | 14°C | 165 mm | 190 h | 7 |
| November | 11°C | 70 mm | 125 h | 7 |
| December | 8°C | 40 mm | 138 h | 12 |
About 2,799 hours of sun a year. Roughly 117 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-24. Full method, licences and the list of sources we rejected are on the methodology page.