| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°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 80603 - Brighton, CO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 18 | 23 | 31 | 41 | 50 | 55 | 54 | 44 | 33 | 21 | 14 | 33 |
| Avg Max Temp (°F) | 42 | 48 | 54 | 62 | 72 | 82 | 88 | 87 | 77 | 67 | 51 | 43 | 64 |
| Avg Precip (In.) | .42 | .41 | 1.25 | 1.79 | 2.43 | 1.67 | 1.59 | 1.52 | 1.15 | .88 | .87 | .41 | 14.39 |