| 2023 Hardiness Zone: | Zone 9a: 20°F to 25°F 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 10a: 30F to 35F |
| Average First Frost Date: | Dec. 1 - Dec. 10 |
| Average Last Frost Date: | Mar. 11 - Mar. 20 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 94952 - Petaluma, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 39 | 41 | 42 | 43 | 46 | 49 | 51 | 51 | 50 | 47 | 42 | 38 | 45 |
| Avg Max Temp (°F) | 57 | 61 | 64 | 68 | 71 | 76 | 79 | 79 | 78 | 74 | 64 | 58 | 69 |
| Avg Precip (In.) | 8.32 | 7.58 | 5.85 | 2.2 | .91 | .21 | .08 | .14 | .46 | 2.07 | 5.44 | 5.82 | 39.07 |