Herald, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 48.4 °F (low) to 74.3 °F (high). Annual precipitation averages 18.9 Inches. Herald is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Jan. 21 - Jan. 31 through the first frost around Dec. 21 - Dec. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 39.0 °F | 55.7 °F | 3.7 in. |
| February | 41.1 °F | 60.9 °F | 3.43 in. |
| March | 44.0 °F | 66.0 °F | 2.74 in. |
| April | 46.5 °F | 71.6 °F | 1.59 in. |
| May | 51.5 °F | 79.4 °F | 0.9 in. |
| June | 55.9 °F | 87.0 °F | 0.19 in. |
| July | 58.6 °F | 92.2 °F | 0.01 in. |
| August | 58.3 °F | 91.3 °F | 0.03 in. |
| September | 55.9 °F | 88.1 °F | 0.11 in. |
| October | 49.6 °F | 78.2 °F | 0.89 in. |
| November | 42.3 °F | 64.9 °F | 1.8 in. |
| December | 38.4 °F | 56.0 °F | 3.47 in. |
| Annual | 48.4 °F | 74.3 °F | 18.86 in. |
| Average First Frost Date | Dec. 21 - Dec. 31 |
| Average Last Frost Date | Jan. 21 - Jan. 31 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9b : 25°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 9b : 25°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |