| 2023 Hardiness Zone: | Zone 9b: 25°F to 30°F |
| 2012 Hardiness Zone: | Zone 9b: 25°F to 30°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: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 61 - 90 days Over 86°F |
Annual Climate Data for ZIP Code 94531 - Antioch, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 38 | 41 | 43 | 46 | 51 | 56 | 58 | 58 | 56 | 51 | 43 | 37 | 48 |
| Avg Max Temp (°F) | 54 | 60 | 64 | 70 | 77 | 83 | 88 | 88 | 84 | 76 | 64 | 55 | 72 |
| Avg Precip (In.) | 3.07 | 2.78 | 2.39 | .85 | .56 | .1 | .03 | .04 | .24 | .81 | 1.85 | 2.13 | 14.86 |