| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 25l - Front Range Fans |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 80235 - Denver, CO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 16 | 19 | 25 | 33 | 42 | 51 | 56 | 55 | 46 | 34 | 24 | 16 | 35 |
| Avg Max Temp (°F) | 44 | 48 | 54 | 61 | 69 | 81 | 86 | 84 | 76 | 65 | 52 | 45 | 64 |
| Avg Precip (In.) | .57 | .58 | 1.44 | 2.34 | 2.69 | 1.96 | 1.78 | 1.79 | 1.31 | 1.04 | 1.09 | .69 | 17.28 |