Monterrey weather by month
Monterrey runs from about 13°C in January to 29°C in May, with June the wettest month at 232 mm.
warmest month
May
29°C
coolest month
January
13°C
wettest month
June
232 mm
worst air month
April
15 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 13°C | 14 mm | 269 h | 14 |
| February | 17°C | 39 mm | 261 h | 14 |
| March | 20°C | 53 mm | 308 h | 12 |
| April | 24°C | 23 mm | 316 h | 15 |
| May | 29°C | 39 mm | 354 h | 14 |
| June | 28°C | 232 mm | 332 h | 10 |
| July | 26°C | 54 mm | 337 h | 11 |
| August | 28°C | 17 mm | 374 h | 11 |
| September | 25°C | 117 mm | 312 h | 12 |
| October | 22°C | 59 mm | 309 h | 13 |
| November | 20°C | 7 mm | 283 h | 15 |
| December | 16°C | 42 mm | 226 h | 14 |
About 3,681 hours of sun a year. Roughly 69 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.