Clearlake Oaks, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 6.6 °C (low) to 22.5 °C (high). Annual precipitation averages 772.2 Millimeters. Clearlake Oaks is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.6 °C | 13.3 °C | 165.35 mm |
| February | 2.1 °C | 14.9 °C | 152.65 mm |
| March | 3.3 °C | 17.2 °C | 99.57 mm |
| April | 4.8 °C | 19.6 °C | 49.53 mm |
| May | 7.8 °C | 23.9 °C | 32 mm |
| June | 11 °C | 29.1 °C | 7.11 mm |
| July | 13.8 °C | 33.6 °C | 0 mm |
| August | 12.9 °C | 33.1 °C | 1.02 mm |
| September | 10.3 °C | 30.4 °C | 2.79 mm |
| October | 6.8 °C | 24.4 °C | 32.51 mm |
| November | 3.2 °C | 17.2 °C | 72.39 mm |
| December | 1.3 °C | 13.1 °C | 157.23 mm |
| Annual | 6.6 °C | 22.5 °C | 772.15 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |