McKinleyville, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 7.6 °C (low) to 15.4 °C (high). Annual precipitation averages 1275.6 Millimeters. McKinleyville is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.3 °C | 13 °C | 219.96 mm |
| February | 5.3 °C | 13.5 °C | 172.47 mm |
| March | 5.6 °C | 13.7 °C | 186.69 mm |
| April | 6.4 °C | 14.1 °C | 110.24 mm |
| May | 8.1 °C | 15.3 °C | 54.61 mm |
| June | 9.6 °C | 16.7 °C | 28.7 mm |
| July | 11.1 °C | 17.3 °C | 6.6 mm |
| August | 11.2 °C | 17.9 °C | 5.84 mm |
| September | 9.8 °C | 18.1 °C | 22.86 mm |
| October | 8 °C | 17.2 °C | 75.95 mm |
| November | 6.4 °C | 14.8 °C | 145.54 mm |
| December | 4.9 °C | 12.7 °C | 246.13 mm |
| Annual | 7.6 °C | 15.4 °C | 1275.59 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 10-20 Days |
| 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 | Moderate Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |