Rock Springs, Wyoming has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -0.8 °C (low) to 14.1 °C (high). Annual precipitation averages 257.8 Millimeters. Rock Springs is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.2 °C | 0.4 °C | 15.24 mm |
| February | -10.2 °C | 2.2 °C | 12.95 mm |
| March | -5.3 °C | 7.9 °C | 18.29 mm |
| April | -1.7 °C | 12.9 °C | 28.19 mm |
| May | 2.8 °C | 18.2 °C | 49.28 mm |
| June | 7.3 °C | 24.7 °C | 21.59 mm |
| July | 11.1 °C | 29.6 °C | 16.26 mm |
| August | 10.2 °C | 28.4 °C | 14.99 mm |
| September | 5.3 °C | 23.2 °C | 26.42 mm |
| October | -0.3 °C | 15.1 °C | 26.16 mm |
| November | -6.2 °C | 6.6 °C | 16 mm |
| December | -11.3 °C | 0.3 °C | 12.45 mm |
| Annual | -0.8 °C | 14.1 °C | 257.82 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |