Walnut Park, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 55.8 °F (low) to 74.4 °F (high). Annual precipitation averages 14.2 Inches. Walnut Park is located in USDA Plant Hardiness Zone 10b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 47.9 °F | 67.5 °F | 3.28 in. |
| February | 49.1 °F | 67.4 °F | 3.62 in. |
| March | 51.2 °F | 68.6 °F | 2.32 in. |
| April | 53.4 °F | 72.0 °F | 0.73 in. |
| May | 57.2 °F | 73.8 °F | 0.29 in. |
| June | 60.7 °F | 76.8 °F | 0.07 in. |
| July | 63.9 °F | 81.9 °F | 0.04 in. |
| August | 64.5 °F | 83.6 °F | 0.02 in. |
| September | 63.2 °F | 82.7 °F | 0.12 in. |
| October | 58.9 °F | 78.7 °F | 0.54 in. |
| November | 52.3 °F | 72.6 °F | 0.77 in. |
| December | 47.4 °F | 67.1 °F | 2.35 in. |
| Annual | 55.8 °F | 74.4 °F | 14.15 in. |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10b : 35°F to 30°F |
| Plant Hardiness Zone - 2012 | Zone 10b : 35°F to 30°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |