Alpine, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 9.5 °C (low) to 24.6 °C (high). Annual precipitation averages 427 Millimeters. Alpine is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 11 - Dec. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.3 °C | 18.6 °C | 76.45 mm |
| February | 5.4 °C | 18.3 °C | 100.08 mm |
| March | 6.1 °C | 19.9 °C | 75.95 mm |
| April | 7.2 °C | 21.9 °C | 31.24 mm |
| May | 9.3 °C | 24.2 °C | 12.45 mm |
| June | 11.8 °C | 28.7 °C | 2.03 mm |
| July | 15.3 °C | 31.8 °C | 3.3 mm |
| August | 16.2 °C | 33.1 °C | 3.3 mm |
| September | 14.7 °C | 31.5 °C | 6.35 mm |
| October | 11.2 °C | 26.9 °C | 17.02 mm |
| November | 7.3 °C | 22.3 °C | 38.1 mm |
| December | 4.7 °C | 18.2 °C | 60.71 mm |
| Annual | 9.5 °C | 24.6 °C | 426.98 mm |
| Average First Frost Date | Dec. 11 - Dec. 20 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |