| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F Zone 4b: -25°F to -20°F Zone 6a: -10°F to -5°F Zone 4a: -30°F to -25°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 5a: -20°F to -15°F Zone 3b: -35°F to -30°F Zone 4a: -30°F to -25°F Zone 4b: -25°F to -20°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| Average First Frost Date: | Sep. 21 - Sep. 30 |
| Average Last Frost Date: | Jun. 1 - Jun. 10 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 18a - Rolling Sagebrush Steppe |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 82901 - Rock Springs, WY | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 14 | 22 | 28 | 37 | 45 | 51 | 49 | 39 | 30 | 19 | 11 | 30 |
| Avg Max Temp (°F) | 31 | 36 | 44 | 54 | 65 | 76 | 84 | 82 | 71 | 59 | 42 | 32 | 56 |
| Avg Precip (In.) | .52 | .45 | .69 | .94 | 1.27 | .74 | .84 | .63 | .85 | .79 | .56 | .47 | 8.76 |