Bath weather by month
Bath runs from about 5°C in January to 17°C in August, with September the wettest month at 211 mm.
warmest month
August
17°C
coolest month
January
5°C
wettest month
September
211 mm
worst air month
March
11 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 5°C | 75 mm | 135 h | 5 |
| February | 8°C | 156 mm | 89 h | 5 |
| March | 7°C | 121 mm | 182 h | 11 |
| April | 9°C | 77 mm | 246 h | 7 |
| May | 13°C | 103 mm | 310 h | 8 |
| June | 14°C | 35 mm | 360 h | 6 |
| July | 16°C | 88 mm | 308 h | 4 |
| August | 17°C | 52 mm | 280 h | 6 |
| September | 14°C | 211 mm | 201 h | 5 |
| October | 12°C | 87 mm | 170 h | 6 |
| November | 8°C | 95 mm | 98 h | 5 |
| December | 7°C | 74 mm | 67 h | 6 |
About 2,446 hours of sun a year. Roughly 119 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.