| 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 Zone 10a: 30°F to 35°F |
| 1990 Hardiness Zone: | Zone 10a: 30F to 35F |
| Average First Frost Date: | Jan. 11 - Jan. 20 |
| 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 95503 - Eureka, CA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 40 | 41 | 42 | 43 | 47 | 50 | 52 | 53 | 51 | 47 | 43 | 40 | 46 |
| Avg Max Temp (°F) | 55 | 56 | 57 | 59 | 62 | 65 | 66 | 67 | 67 | 63 | 58 | 55 | 61 |
| Avg Precip (In.) | 6.8 | 6.13 | 6.25 | 3.37 | 1.68 | .68 | .15 | .39 | .93 | 2.51 | 6.61 | 6.88 | 42.38 |