Lennox, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 13.5 °C (low) to 21.7 °C (high). Annual precipitation averages 345.2 Millimeters. Lennox is located in USDA Plant Hardiness Zone 10b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 9.6 °C | 18.9 °C | 81.28 mm |
| February | 9.9 °C | 18.7 °C | 90.42 mm |
| March | 11.1 °C | 19.1 °C | 54.61 mm |
| April | 12.1 °C | 20.5 °C | 16 mm |
| May | 14.1 °C | 21.3 °C | 6.86 mm |
| June | 15.9 °C | 22.6 °C | 1.52 mm |
| July | 17.6 °C | 24.5 °C | 0.76 mm |
| August | 17.9 °C | 25.3 °C | 0.51 mm |
| September | 17.3 °C | 25.2 °C | 3.3 mm |
| October | 15.2 °C | 23.9 °C | 14.73 mm |
| November | 11.8 °C | 21.4 °C | 17.78 mm |
| December | 9.3 °C | 18.8 °C | 57.4 mm |
| Annual | 13.5 °C | 21.7 °C | 345.17 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10b : 1.7°C to 4.4°C |
| Plant Hardiness Zone - 2012 | Zone 10b : 1.7°C to 4.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |