| 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 |
| 1990 Hardiness Zone: | Zone 9b: 25F to 30F |
| Average First Frost Date: | Dec. 11 - Dec. 20 |
| 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 95448 - Healdsburg, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 39 | 42 | 43 | 45 | 49 | 53 | 54 | 54 | 53 | 48 | 43 | 38 | 47 |
| Avg Max Temp (°F) | 57 | 62 | 65 | 72 | 79 | 86 | 90 | 88 | 85 | 77 | 64 | 57 | 73 |
| Avg Precip (In.) | 8.68 | 7.97 | 6.46 | 2.26 | .97 | .17 | .07 | .12 | .55 | 2.14 | 5.74 | 6.51 | 41.63 |