| 2023 Hardiness Zone: | Zone 10b: 35°F to 40°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: | Jan. 21 - Jan. 31 |
| Average Last Frost Date: | Jan. 21 - Jan. 31 |
| Koppen-Geiger Climate Zone: | Csb - Warm-Summer Mediterranean Climate |
| Ecoregion: | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 94941 - Mill Valley, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 42 | 44 | 45 | 47 | 49 | 52 | 54 | 54 | 54 | 51 | 46 | 42 | 48 |
| Avg Max Temp (°F) | 56 | 61 | 64 | 68 | 72 | 77 | 79 | 79 | 78 | 74 | 63 | 56 | 69 |
| Avg Precip (In.) | 7.98 | 7.61 | 5.97 | 2.11 | 1.06 | .26 | .09 | .13 | .45 | 1.93 | 5.96 | 5.86 | 39.41 |