| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | Jun. 1 - Jun. 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 25l - Front Range Fans |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 80401 - Golden, CO | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 16 | 21 | 29 | 38 | 46 | 52 | 50 | 42 | 31 | 21 | 14 | 31 |
| Avg Max Temp (°F) | 44 | 47 | 52 | 58 | 67 | 78 | 84 | 82 | 74 | 64 | 51 | 44 | 62 |
| Avg Precip (In.) | .54 | .55 | 1.59 | 2.28 | 2.88 | 2.01 | 1.77 | 1.81 | 1.41 | 1.09 | 1.11 | .73 | 17.78 |