Fulton, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 6.8 °C (low) to 21.6 °C (high). Annual precipitation averages 877.8 Millimeters. Fulton is located in USDA Plant Hardiness Zone 9a. 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 | 3.2 °C | 14.2 °C | 171.7 mm |
| February | 3.9 °C | 16.2 °C | 171.7 mm |
| March | 4.9 °C | 17.9 °C | 122.17 mm |
| April | 5.8 °C | 20.1 °C | 57.15 mm |
| May | 7.8 °C | 22.9 °C | 36.32 mm |
| June | 9.7 °C | 26.4 °C | 7.62 mm |
| July | 10.8 °C | 27.7 °C | 0.76 mm |
| August | 10.9 °C | 28 °C | 2.03 mm |
| September | 9.7 °C | 27.8 °C | 3.81 mm |
| October | 7.6 °C | 24.7 °C | 40.89 mm |
| November | 4.7 °C | 18.6 °C | 92.96 mm |
| December | 2.8 °C | 14.2 °C | 170.69 mm |
| Annual | 6.8 °C | 21.6 °C | 877.8 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 9a : -6.7°C to -3.9°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 |