Cotati, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.9 °C (low) to 21 °C (high). Annual precipitation averages 815.3 Millimeters. Cotati is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.3 °C | 14 °C | 160.02 mm |
| February | 4.2 °C | 16.1 °C | 163.32 mm |
| March | 5.1 °C | 17.8 °C | 111.25 mm |
| April | 5.8 °C | 19.4 °C | 51.56 mm |
| May | 7.7 °C | 21.9 °C | 32.26 mm |
| June | 9.6 °C | 25.1 °C | 7.87 mm |
| July | 10.7 °C | 26.5 °C | 0.76 mm |
| August | 10.9 °C | 26.8 °C | 2.79 mm |
| September | 9.8 °C | 27.1 °C | 3.05 mm |
| October | 7.7 °C | 24.3 °C | 37.85 mm |
| November | 4.8 °C | 18.5 °C | 85.34 mm |
| December | 3.1 °C | 14.1 °C | 159.26 mm |
| Annual | 6.9 °C | 21 °C | 815.33 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |