Dallas weather by month
Dallas runs from about 5°C in January to 31°C in August, with May the wettest month at 262 mm.
warmest month
August
31°C
coolest month
January
5°C
wettest month
May
262 mm
worst air month
August
14 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | 5°C | 95 mm | 233 h | 12 |
| February | 13°C | 69 mm | 231 h | 11 |
| March | 16°C | 136 mm | 274 h | 8 |
| April | 20°C | 194 mm | 265 h | 8 |
| May | 24°C | 262 mm | 303 h | 11 |
| June | 28°C | 85 mm | 353 h | 11 |
| July | 29°C | 90 mm | 368 h | 9 |
| August | 31°C | 20 mm | 391 h | 14 |
| September | 26°C | 65 mm | 313 h | 14 |
| October | 24°C | 7 mm | 335 h | 10 |
| November | 16°C | 135 mm | 243 h | 7 |
| December | 12°C | 136 mm | 216 h | 8 |
About 3,525 hours of sun a year. Roughly 132 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 2026-05-23. Full method, licences and the list of sources we rejected are on the methodology page.