| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 21 - May 31 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 25l - Front Range Fans |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 80125 - Littleton, CO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 19 | 26 | 33 | 43 | 52 | 58 | 57 | 47 | 35 | 24 | 16 | 35 |
| Avg Max Temp (°F) | 45 | 48 | 55 | 61 | 70 | 82 | 87 | 86 | 77 | 67 | 53 | 46 | 65 |
| Avg Precip (In.) | .55 | .58 | 1.59 | 2.29 | 2.74 | 1.67 | 1.51 | 1.61 | 1.44 | 1.17 | 1.21 | .75 | 17.11 |