| 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 Zone 10a: 30°F to 35°F |
| 1990 Hardiness Zone: | Zone 9b: 25F to 30F |
| Average First Frost Date: | Dec. 11 - Dec. 20 |
| Average Last Frost Date: | Feb. 11 - Feb. 20 |
| 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 94513 - Brentwood, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 38 | 41 | 44 | 47 | 51 | 56 | 58 | 58 | 56 | 51 | 43 | 37 | 48 |
| Avg Max Temp (°F) | 54 | 60 | 65 | 71 | 78 | 85 | 90 | 89 | 86 | 77 | 64 | 55 | 73 |
| Avg Precip (In.) | 2.89 | 2.62 | 2.25 | .82 | .5 | .1 | .03 | .04 | .24 | .8 | 1.74 | 1.96 | 14 |