Fillmore, California has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 50.1 °F (low) to 75.4 °F (high). Annual precipitation averages 19.3 Inches. Fillmore is located in USDA Plant Hardiness Zone 10a. The growing season typically runs from the last frost around Feb. 1 - Feb. 10 through the first frost around Jan. 1 - Jan. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 44.2 °F | 66.5 °F | 4.62 in. |
| February | 44.1 °F | 66.6 °F | 4.97 in. |
| March | 45.6 °F | 68.4 °F | 3.11 in. |
| April | 47.0 °F | 72.1 °F | 0.84 in. |
| May | 50.7 °F | 74.9 °F | 0.41 in. |
| June | 54.0 °F | 79.2 °F | 0.04 in. |
| July | 57.6 °F | 85.3 °F | 0.05 in. |
| August | 57.9 °F | 87.3 °F | 0.0 in. |
| September | 56.5 °F | 85.9 °F | 0.1 in. |
| October | 52.8 °F | 80.4 °F | 0.82 in. |
| November | 47.4 °F | 72.5 °F | 1.23 in. |
| December | 43.3 °F | 66.1 °F | 3.11 in. |
| Annual | 50.1 °F | 75.4 °F | 19.3 in. |
| Average First Frost Date | Jan. 1 - Jan. 10 |
| Average Last Frost Date | Feb. 1 - Feb. 10 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 10a : 30°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9b : 25°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |