Star Valley Ranch, Wyoming has a Subarctic With Cool Summers And Year Around Rainfall climate (Köppen classification: Dfc). Average annual temperatures range from -3.8 °C (low) to 12 °C (high). Annual precipitation averages 658.4 Millimeters. Star Valley Ranch is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Aug. 21 - Aug. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14 °C | -1.4 °C | 62.74 mm |
| February | -13.1 °C | 0.7 °C | 60.96 mm |
| March | -8.6 °C | 5.7 °C | 51.82 mm |
| April | -3.9 °C | 9.8 °C | 64.01 mm |
| May | 0.8 °C | 16.2 °C | 84.07 mm |
| June | 3.6 °C | 21.4 °C | 52.83 mm |
| July | 6.3 °C | 27 °C | 25.91 mm |
| August | 5.7 °C | 26.6 °C | 33.78 mm |
| September | 1.6 °C | 21.4 °C | 45.97 mm |
| October | -2.8 °C | 13.1 °C | 50.8 mm |
| November | -8.3 °C | 5 °C | 57.66 mm |
| December | -13.3 °C | -1.4 °C | 67.82 mm |
| Annual | -3.8 °C | 12 °C | 658.37 mm |
| Average First Frost Date | Aug. 21 - Aug. 31 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfc - Subarctic With Cool Summers And Year Around Rainfall |