San Blas weather by month
San Blas runs from about 27°C in November to 28°C in January, with October the wettest month at 314 mm.
warmest month
January
28°C
coolest month
November
27°C
wettest month
October
314 mm
worst air month
May
13 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 28°C | 70 mm | 341 h | 8 |
| February | 28°C | 91 mm | 306 h | 11 |
| March | 28°C | 57 mm | 341 h | 10 |
| April | 28°C | 163 mm | 317 h | 9 |
| May | 28°C | 210 mm | 296 h | 13 |
| June | 28°C | 168 mm | 279 h | 9 |
| July | 28°C | 266 mm | 252 h | 10 |
| August | 28°C | 274 mm | 273 h | 7 |
| September | 28°C | 179 mm | 248 h | 5 |
| October | 28°C | 314 mm | 277 h | 3 |
| November | 27°C | 143 mm | 290 h | 6 |
| December | 28°C | 268 mm | 285 h | 7 |
About 3,505 hours of sun a year. Roughly 219 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 2026-05-25. Full method, licences and the list of sources we rejected are on the methodology page.