| 2023 Hardiness Zone: | Zone 8b: 15°F to 20°F Zone 9a: 20°F to 25°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 |
| 1990 Hardiness Zone: | Zone 9a: 20F to 25F |
| Average First Frost Date: | Nov. 11 - Nov. 20 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Csa - Hot-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 95945 - Grass Valley, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 32 | 34 | 36 | 40 | 45 | 52 | 56 | 55 | 51 | 44 | 36 | 32 | 43 |
| Avg Max Temp (°F) | 52 | 55 | 57 | 64 | 72 | 81 | 88 | 87 | 82 | 72 | 58 | 52 | 68 |
| Avg Precip (In.) | 10.34 | 9.79 | 8.72 | 3.94 | 2.07 | .64 | .23 | .25 | 1.12 | 2.94 | 7.32 | 8.28 | 55.64 |