Jeffrey City, Wyoming has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 29.7 °F (low) to 56.6 °F (high). Annual precipitation averages 9.7 Inches. Jeffrey City is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 11.4 °F | 31.9 °F | 0.35 in. |
| February | 12.5 °F | 34.3 °F | 0.51 in. |
| March | 21.1 °F | 44.7 °F | 0.77 in. |
| April | 27.2 °F | 53.7 °F | 1.4 in. |
| May | 35.9 °F | 63.8 °F | 1.9 in. |
| June | 44.3 °F | 76.4 °F | 0.94 in. |
| July | 51.3 °F | 85.4 °F | 0.66 in. |
| August | 49.9 °F | 83.3 °F | 0.53 in. |
| September | 40.6 °F | 72.8 °F | 0.82 in. |
| October | 29.8 °F | 58.0 °F | 0.94 in. |
| November | 20.2 °F | 42.6 °F | 0.48 in. |
| December | 11.9 °F | 32.0 °F | 0.44 in. |
| Annual | 29.7 °F | 56.6 °F | 9.74 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |