Des Moines weather by month
Des Moines runs from about -7°C in January to 24°C in June, with June the wettest month at 204 mm.
warmest month
June
24°C
coolest month
January
-7°C
wettest month
June
204 mm
worst air month
February
10 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -7°C | 51 mm | 169 h | 8 |
| February | 3°C | 13 mm | 273 h | 10 |
| March | 7°C | 61 mm | 259 h | 9 |
| April | 12°C | 117 mm | 297 h | 6 |
| May | 18°C | 153 mm | 353 h | 6 |
| June | 24°C | 204 mm | 351 h | 8 |
| July | 23°C | 179 mm | 392 h | 10 |
| August | 23°C | 35 mm | 352 h | 10 |
| September | 20°C | 57 mm | 331 h | 9 |
| October | 15°C | 57 mm | 310 h | 7 |
| November | 6°C | 103 mm | 174 h | 6 |
| December | -1°C | 40 mm | 148 h | 9 |
About 3,409 hours of sun a year. Roughly 107 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.