Piru, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 10.4 °C (low) to 24.5 °C (high). Annual precipitation averages 463.8 Millimeters. Piru is located in USDA Plant Hardiness Zone 10a. 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 | 7.2 °C | 18.8 °C | 112.78 mm |
| February | 7 °C | 19.1 °C | 123.44 mm |
| March | 7.8 °C | 20.6 °C | 74.17 mm |
| April | 8.5 °C | 22.4 °C | 20.07 mm |
| May | 10.4 °C | 24.2 °C | 11.94 mm |
| June | 12.2 °C | 27 °C | 1.02 mm |
| July | 14.6 °C | 30.5 °C | 1.52 mm |
| August | 14.8 °C | 31.9 °C | 0.25 mm |
| September | 14.1 °C | 30.7 °C | 3.05 mm |
| October | 12 °C | 27.1 °C | 17.53 mm |
| November | 9.2 °C | 22.7 °C | 26.42 mm |
| December | 6.8 °C | 18.6 °C | 71.63 mm |
| Annual | 10.4 °C | 24.5 °C | 463.82 mm |
| 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 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |