| 2023 Hardiness Zone: | Zone 9a: 20°F to 25°F Zone 9b: 25°F to 30°F |
| 2012 Hardiness Zone: | Zone 9a: 20°F to 25°F Zone 9b: 25°F to 30°F Zone 10a: 30°F to 35°F |
| 1990 Hardiness Zone: | Zone 9b: 25F to 30F |
| Average First Frost Date: | Dec. 1 - Dec. 10 |
| Average Last Frost Date: | Feb. 21 - Feb. 29 |
| Koppen-Geiger Climate Zone: | Csa - Hot-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 91 - 120 days Over 86°F |
Annual Climate Data for ZIP Code 95688 - Vacaville, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 37 | 41 | 43 | 46 | 51 | 56 | 58 | 57 | 55 | 50 | 42 | 37 | 48 |
| Avg Max Temp (°F) | 56 | 62 | 66 | 73 | 80 | 88 | 93 | 93 | 89 | 79 | 65 | 56 | 75 |
| Avg Precip (In.) | 5.4 | 4.93 | 3.76 | 1.2 | .64 | .11 | .05 | .05 | .3 | 1.23 | 3.24 | 3.69 | 24.59 |