Forestville, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 44.4 °F (low) to 71.1 °F (high). Annual precipitation averages 47.3 Inches. Forestville is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.0 °F | 57.6 °F | 10.09 in. |
| February | 39.3 °F | 61.1 °F | 10.04 in. |
| March | 41.1 °F | 64.4 °F | 6.16 in. |
| April | 42.7 °F | 68.6 °F | 2.7 in. |
| May | 46.1 °F | 73.9 °F | 1.41 in. |
| June | 49.6 °F | 80.0 °F | 0.47 in. |
| July | 51.3 °F | 82.1 °F | 0.02 in. |
| August | 51.4 °F | 82.7 °F | 0.1 in. |
| September | 49.5 °F | 82.6 °F | 0.17 in. |
| October | 45.8 °F | 77.1 °F | 1.96 in. |
| November | 40.7 °F | 65.5 °F | 4.85 in. |
| December | 37.4 °F | 57.5 °F | 9.34 in. |
| Annual | 44.4 °F | 71.1 °F | 47.31 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |