Calistoga, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 7.7 °C (low) to 23.4 °C (high). Annual precipitation averages 979.9 Millimeters. Calistoga is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.6 °C | 14.8 °C | 201.17 mm |
| February | 4.1 °C | 16.3 °C | 212.6 mm |
| March | 5.2 °C | 18.2 °C | 128.78 mm |
| April | 6.8 °C | 21.5 °C | 62.99 mm |
| May | 8.9 °C | 25.1 °C | 32.26 mm |
| June | 10.9 °C | 29.8 °C | 7.62 mm |
| July | 12.2 °C | 32.4 °C | 0 mm |
| August | 11.9 °C | 32.2 °C | 1.52 mm |
| September | 11.2 °C | 31.1 °C | 3.3 mm |
| October | 9.1 °C | 26.3 °C | 46.23 mm |
| November | 5.5 °C | 18.7 °C | 90.93 mm |
| December | 3.4 °C | 14.4 °C | 192.53 mm |
| Annual | 7.7 °C | 23.4 °C | 979.93 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 20-30 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 | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |