Mad River, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 38.9 °F (low) to 67.9 °F (high). Annual precipitation averages 57.6 Inches. Mad River is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 31.5 °F | 50.9 °F | 9.92 in. |
| February | 31.8 °F | 54.1 °F | 9.22 in. |
| March | 33.3 °F | 57.7 °F | 8.05 in. |
| April | 35.3 °F | 61.4 °F | 4.59 in. |
| May | 40.2 °F | 69.6 °F | 2.52 in. |
| June | 45.3 °F | 77.9 °F | 0.98 in. |
| July | 49.9 °F | 88.6 °F | 0.15 in. |
| August | 49.0 °F | 89.2 °F | 0.12 in. |
| September | 45.2 °F | 85.5 °F | 0.52 in. |
| October | 39.0 °F | 72.4 °F | 3.23 in. |
| November | 34.5 °F | 57.4 °F | 6.26 in. |
| December | 31.2 °F | 49.7 °F | 11.99 in. |
| Annual | 38.9 °F | 67.9 °F | 57.55 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |