| 2023 Hardiness Zone: | Zone 9b: 25°F to 30°F Zone 10a: 30°F to 35°F |
| 2012 Hardiness Zone: | Zone 9b: 25°F to 30°F |
| 1990 Hardiness Zone: | Zone 10b: 35F to 40F |
| Average First Frost Date: | Dec. 11 - Dec. 20 |
| Average Last Frost Date: | Feb. 21 - Feb. 29 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 91 - 120 days Over 86°F |
Annual Climate Data for ZIP Code 91306 - Winnetka, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 41 | 42 | 43 | 46 | 50 | 54 | 57 | 58 | 56 | 51 | 43 | 40 | 48 |
| Avg Max Temp (°F) | 67 | 69 | 71 | 77 | 80 | 87 | 94 | 95 | 91 | 84 | 74 | 68 | 80 |
| Avg Precip (In.) | 3.95 | 4.11 | 3.52 | .83 | .28 | .06 | .01 | .16 | .24 | .57 | 1.41 | 2.17 | 17.32 |