Inverness, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 7.7 °C (low) to 18.7 °C (high). Annual precipitation averages 861.1 Millimeters. Inverness is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.1 °C | 13.8 °C | 167.64 mm |
| February | 5.5 °C | 14.8 °C | 166.37 mm |
| March | 6.1 °C | 15.5 °C | 112.52 mm |
| April | 6.7 °C | 17.4 °C | 63.25 mm |
| May | 8.2 °C | 18.9 °C | 35.81 mm |
| June | 9.6 °C | 21.3 °C | 8.38 mm |
| July | 10.7 °C | 22.3 °C | 0.51 mm |
| August | 11.1 °C | 23.2 °C | 2.54 mm |
| September | 10.1 °C | 23.6 °C | 3.81 mm |
| October | 8.4 °C | 22 °C | 42.93 mm |
| November | 6.4 °C | 17.2 °C | 85.85 mm |
| December | 4.7 °C | 13.8 °C | 171.45 mm |
| Annual | 7.7 °C | 18.7 °C | 861.06 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |