Ukiah, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 7.3 °C (low) to 23.1 °C (high). Annual precipitation averages 983.2 Millimeters. Ukiah is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.1 °C | 14.1 °C | 196.34 mm |
| February | 3.6 °C | 15.7 °C | 175.51 mm |
| March | 4.7 °C | 18.2 °C | 137.67 mm |
| April | 5.9 °C | 20.3 °C | 68.33 mm |
| May | 8.3 °C | 24.5 °C | 36.32 mm |
| June | 11 °C | 28.9 °C | 9.4 mm |
| July | 12.9 °C | 33.6 °C | 0.76 mm |
| August | 12.3 °C | 33.4 °C | 2.03 mm |
| September | 10.5 °C | 31.2 °C | 3.3 mm |
| October | 7.6 °C | 25.3 °C | 44.96 mm |
| November | 4.6 °C | 17.8 °C | 104.65 mm |
| December | 2.6 °C | 13.7 °C | 203.96 mm |
| Annual | 7.3 °C | 23.1 °C | 983.23 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 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 | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |