West Covina, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 12.5 °C (low) to 26.5 °C (high). Annual precipitation averages 398.8 Millimeters. West Covina is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.1 °C | 20.8 °C | 91.44 mm |
| February | 8.6 °C | 20.9 °C | 104.14 mm |
| March | 9.7 °C | 22.2 °C | 60.71 mm |
| April | 10.9 °C | 24.8 °C | 21.08 mm |
| May | 13.3 °C | 26.3 °C | 9.65 mm |
| June | 15.3 °C | 29.3 °C | 3.05 mm |
| July | 17.2 °C | 32.9 °C | 1.52 mm |
| August | 17.6 °C | 34.1 °C | 0.25 mm |
| September | 16.6 °C | 32.8 °C | 3.3 mm |
| October | 14.1 °C | 29 °C | 16.51 mm |
| November | 10.5 °C | 24.1 °C | 21.84 mm |
| December | 7.7 °C | 20.4 °C | 65.28 mm |
| Annual | 12.5 °C | 26.5 °C | 398.77 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 10a : -1.1°C to 1.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |