Alta Sierra, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 7.8 °C (low) to 21.4 °C (high). Annual precipitation averages 1165.9 Millimeters. Alta Sierra is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.2 °C | 9.4 °C | 166.12 mm |
| February | -1.4 °C | 9.1 °C | 170.43 mm |
| March | -0.6 °C | 10.9 °C | 134.62 mm |
| April | 1.2 °C | 13.9 °C | 72.14 mm |
| May | 5.1 °C | 18.7 °C | 36.58 mm |
| June | 9.3 °C | 24.2 °C | 12.95 mm |
| July | 13.3 °C | 28.3 °C | 6.86 mm |
| August | 12.9 °C | 28 °C | 4.83 mm |
| September | 10.3 °C | 25.1 °C | 6.1 mm |
| October | 5.7 °C | 19.2 °C | 36.58 mm |
| November | 1.7 °C | 12.7 °C | 67.56 mm |
| December | -1.5 °C | 8.6 °C | 148.59 mm |
| Annual | 4.6 °C | 17.3 °C | 863.36 mm |
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.2 °C | 12.2 °C | 202.18 mm |
| February | 2.6 °C | 13.5 °C | 182.63 mm |
| March | 3.7 °C | 15.7 °C | 183.39 mm |
| April | 5.3 °C | 18.4 °C | 100.58 mm |
| May | 8.8 °C | 23.1 °C | 56.39 mm |
| June | 12.4 °C | 28.2 °C | 15.49 mm |
| July | 15.8 °C | 32.6 °C | 0.25 mm |
| August | 15.6 °C | 32.5 °C | 1.52 mm |
| September | 12.7 °C | 29.8 °C | 9.65 mm |
| October | 8.7 °C | 23.8 °C | 57.66 mm |
| November | 4.4 °C | 15.9 °C | 126.49 mm |
| December | 1.9 °C | 11.4 °C | 229.62 mm |
| Annual | 7.8 °C | 21.4 °C | 1165.85 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Jun. 11 - Jun. 20 |
| Average Days With Frost | 75-100 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 | Abnormally Dry |
| Köppen Climate Classification | BSh - Hot Semi-Arid Climate |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |