| 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 9b: 25°F to 30°F |
| 1990 Hardiness Zone: | Zone 8b: 15F to 20F |
| Average First Frost Date: | Nov. 21 - Nov. 30 |
| Average Last Frost Date: | Apr. 1 - Apr. 10 |
| Koppen-Geiger Climate Zone: | Csa - Hot-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | 91 - 120 days Over 86°F |
Annual Climate Data for ZIP Code 95485 - Upper Lake, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 34 | 36 | 38 | 40 | 44 | 50 | 54 | 53 | 49 | 44 | 38 | 33 | 43 |
| Avg Max Temp (°F) | 54 | 57 | 62 | 67 | 75 | 83 | 91 | 91 | 86 | 75 | 60 | 54 | 71 |
| Avg Precip (In.) | 8.24 | 7.65 | 6.23 | 2.57 | 1.15 | .22 | .06 | .13 | .63 | 2.03 | 5.52 | 6.2 | 40.65 |