Ruth, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 3 °C (low) to 20.5 °C (high). Annual precipitation averages 1591.1 Millimeters. Ruth is located in USDA Plant Hardiness Zone 8a. 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 | -1.1 °C | 10.2 °C | 295.15 mm |
| February | -0.8 °C | 12.4 °C | 229.87 mm |
| March | 0.3 °C | 14.5 °C | 232.92 mm |
| April | 1.4 °C | 17.3 °C | 119.13 mm |
| May | 4 °C | 22.3 °C | 62.74 mm |
| June | 6.6 °C | 27.2 °C | 25.91 mm |
| July | 9.2 °C | 33 °C | 3.81 mm |
| August | 8.4 °C | 32.9 °C | 3.81 mm |
| September | 5.8 °C | 29.9 °C | 12.95 mm |
| October | 2.6 °C | 23.2 °C | 86.61 mm |
| November | 0.4 °C | 14.1 °C | 169.16 mm |
| December | -1.2 °C | 9.4 °C | 349 mm |
| Annual | 3 °C | 20.5 °C | 1591.06 mm |
| 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 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 | Csb - Warm-Summer Mediterranean Climate |