Ralston, Wyoming has a Cold Desert Climate climate (Köppen classification: BWk). Average annual temperatures range from 32.5 °F (low) to 58.9 °F (high). Annual precipitation averages 7.7 Inches. Ralston is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 11.3 °F | 34.4 °F | 0.2 in. |
| February | 14.5 °F | 37.9 °F | 0.22 in. |
| March | 23.5 °F | 49.5 °F | 0.31 in. |
| April | 31.4 °F | 57.8 °F | 0.72 in. |
| May | 40.9 °F | 66.8 °F | 1.5 in. |
| June | 49.0 °F | 77.1 °F | 1.33 in. |
| July | 55.1 °F | 85.9 °F | 0.97 in. |
| August | 53.0 °F | 84.5 °F | 0.54 in. |
| September | 44.2 °F | 74.2 °F | 0.79 in. |
| October | 32.8 °F | 59.2 °F | 0.67 in. |
| November | 21.5 °F | 44.7 °F | 0.25 in. |
| December | 13.0 °F | 34.7 °F | 0.18 in. |
| Annual | 32.5 °F | 58.9 °F | 7.68 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BWk - Cold Desert Climate |