Santa Ynez, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 8 °C (low) to 23.6 °C (high). Annual precipitation averages 502.4 Millimeters. Santa Ynez is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 1 - Feb. 10 through the first frost around Dec. 21 - Dec. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.4 °C | 18.3 °C | 116.59 mm |
| February | 5.1 °C | 18.3 °C | 116.08 mm |
| March | 5.9 °C | 19.5 °C | 93.98 mm |
| April | 6.7 °C | 21.8 °C | 29.72 mm |
| May | 8.6 °C | 23.9 °C | 10.92 mm |
| June | 10.2 °C | 26.3 °C | 1.27 mm |
| July | 12.1 °C | 29.2 °C | 1.02 mm |
| August | 12.3 °C | 29.9 °C | 0 mm |
| September | 11.3 °C | 29.2 °C | 1.78 mm |
| October | 9.2 °C | 26.6 °C | 19.81 mm |
| November | 6.1 °C | 21.8 °C | 33.02 mm |
| December | 3.9 °C | 18.1 °C | 78.23 mm |
| Annual | 8 °C | 23.6 °C | 502.42 mm |
| Average First Frost Date | Dec. 21 - Dec. 31 |
| Average Last Frost Date | Feb. 1 - Feb. 10 |
| Average Days With Frost | 10-20 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 |