Colfax, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 8.1 °C (low) to 21.3 °C (high). Annual precipitation averages 1185.4 Millimeters. Colfax is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.5 °C | 12.2 °C | 208.53 mm |
| February | 2.8 °C | 13.2 °C | 207.52 mm |
| March | 3.9 °C | 15.3 °C | 187.2 mm |
| April | 5.5 °C | 18.1 °C | 98.81 mm |
| May | 9.1 °C | 22.8 °C | 50.29 mm |
| June | 12.4 °C | 28.1 °C | 18.03 mm |
| July | 16 °C | 32.5 °C | 0.51 mm |
| August | 16.2 °C | 32.4 °C | 2.03 mm |
| September | 13.1 °C | 29.7 °C | 7.87 mm |
| October | 8.9 °C | 23.5 °C | 56.9 mm |
| November | 4.9 °C | 15.8 °C | 118.11 mm |
| December | 2.2 °C | 11.4 °C | 229.62 mm |
| Annual | 8.1 °C | 21.3 °C | 1185.42 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |