| 2023 Hardiness Zone: | Zone 9b: 25°F to 30°F Zone 10a: 30°F to 35°F | |
| 2012 Hardiness Zone: | Zone 9a: 20°F to 25°F Zone 9b: 25°F to 30°F | |
| 1990 Hardiness Zone: | Zone 9a: 20F to 25F | |
| Average First Frost Date: | Dec. 1 - Dec. 10 | |
| Average Last Frost Date: | Mar. 1 - Mar. 10 | |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate | |
| Ecoregion: | ||
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 121 - 150 days Over 86°F |
Annual Climate Data for ZIP Code 92596 - Winchester, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 37 | 39 | 41 | 44 | 50 | 54 | 59 | 60 | 56 | 49 | 41 | 36 | 47 |
| Avg Max Temp (°F) | 66 | 68 | 69 | 75 | 81 | 90 | 97 | 97 | 92 | 83 | 73 | 66 | 80 |
| Avg Precip (In.) | 2.79 | 2.76 | 2.47 | .71 | .32 | .07 | .07 | .29 | .32 | .36 | .83 | 1.19 | 12.17 |