| 2023 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°F Zone 9b: 25°F to 30°F |
| 2012 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°F Zone 8a: 10°F to 15°F Zone 9b: 25°F to 30°F |
| 1990 Hardiness Zone: | Zone 9a: 20F to 25F |
| Average First Frost Date: | Nov. 1 - Nov. 10 |
| Average Last Frost Date: | Apr. 11 - Apr. 20 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 91 - 120 days Over 86°F |
Annual Climate Data for ZIP Code 95573 - Willow Creek, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 33 | 35 | 37 | 39 | 43 | 48 | 52 | 51 | 47 | 41 | 38 | 33 | 41 |
| Avg Max Temp (°F) | 51 | 56 | 61 | 68 | 76 | 85 | 93 | 92 | 86 | 73 | 57 | 49 | 71 |
| Avg Precip (In.) | 9.02 | 8.65 | 7.54 | 3.3 | 1.91 | .61 | .14 | .41 | 1.11 | 3.08 | 7.78 | 9.05 | 52.59 |