Richfield, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 49.1 °F (low) to 75.1 °F (high). Annual precipitation averages 23.5 Inches. Richfield is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 37.9 °F | 56.3 °F | 4.67 in. |
| February | 40.1 °F | 60.8 °F | 3.96 in. |
| March | 42.7 °F | 65.8 °F | 3.29 in. |
| April | 45.7 °F | 71.3 °F | 1.46 in. |
| May | 52.6 °F | 80.2 °F | 1.23 in. |
| June | 59.3 °F | 88.5 °F | 0.42 in. |
| July | 62.9 °F | 95.0 °F | 0.03 in. |
| August | 61.1 °F | 93.6 °F | 0.09 in. |
| September | 57.4 °F | 89.9 °F | 0.22 in. |
| October | 50.3 °F | 78.9 °F | 0.9 in. |
| November | 42.0 °F | 64.7 °F | 2.67 in. |
| December | 37.4 °F | 55.9 °F | 4.54 in. |
| Annual | 49.1 °F | 75.1 °F | 23.48 in. |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |