Star Valley, Arizona has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 6.3 °C (low) to 23.1 °C (high). Annual precipitation averages 520.4 Millimeters. Star Valley is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.6 °C | 13.1 °C | 62.74 mm |
| February | -0.8 °C | 14.4 °C | 65.53 mm |
| March | 1.3 °C | 17.7 °C | 52.07 mm |
| April | 4.2 °C | 21.6 °C | 20.32 mm |
| May | 7.7 °C | 26.3 °C | 14.73 mm |
| June | 12.4 °C | 32.4 °C | 7.37 mm |
| July | 16.8 °C | 33.8 °C | 69.85 mm |
| August | 16.4 °C | 32.6 °C | 71.88 mm |
| September | 12.9 °C | 29.9 °C | 38.1 mm |
| October | 6.9 °C | 24.3 °C | 32 mm |
| November | 1.4 °C | 17.9 °C | 32 mm |
| December | -1.5 °C | 12.7 °C | 53.85 mm |
| Annual | 6.3 °C | 23.1 °C | 520.44 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |