Denver weather by month
Denver runs from about -5°C in January to 24°C in July, with April the wettest month at 61 mm.
warmest month
July
24°C
coolest month
January
-5°C
wettest month
April
61 mm
worst air month
July
11 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -5°C | 20 mm | 243 h | 10 |
| February | -1°C | 56 mm | 256 h | 9 |
| March | 2°C | 60 mm | 305 h | 8 |
| April | 9°C | 61 mm | 312 h | 7 |
| May | 14°C | 49 mm | 388 h | 9 |
| June | 23°C | 6 mm | 386 h | 9 |
| July | 24°C | 16 mm | 412 h | 11 |
| August | 24°C | 25 mm | 346 h | 10 |
| September | 20°C | 17 mm | 341 h | 9 |
| October | 14°C | 17 mm | 312 h | 6 |
| November | 1°C | 53 mm | 233 h | 7 |
| December | 2°C | 6 mm | 249 h | 8 |
About 3,783 hours of sun a year. Roughly 41 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.