| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 25d - Flat to Rolling Plains |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 80231 - Denver, CO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 19 | 25 | 32 | 41 | 50 | 56 | 55 | 45 | 34 | 23 | 17 | 34 |
| Avg Max Temp (°F) | 44 | 48 | 54 | 61 | 71 | 82 | 89 | 86 | 78 | 67 | 52 | 45 | 65 |
| Avg Precip (In.) | .5 | .49 | 1.47 | 2.06 | 2.76 | 1.93 | 2.35 | 2 | 1.38 | 1.01 | 1.13 | .65 | 17.73 |