Pioneer, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 48.4 °F (low) to 69.6 °F (high). Annual precipitation averages 45.1 Inches. Pioneer is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Dec. 11 - Dec. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.5 °F | 53.6 °F | 8.14 in. |
| February | 38.3 °F | 54.7 °F | 7.55 in. |
| March | 39.9 °F | 58.2 °F | 6.86 in. |
| April | 42.3 °F | 63.6 °F | 4.06 in. |
| May | 48.6 °F | 72.2 °F | 2.64 in. |
| June | 56.3 °F | 82.1 °F | 0.51 in. |
| July | 63.6 °F | 90.0 °F | 0.04 in. |
| August | 63.3 °F | 89.7 °F | 0.16 in. |
| September | 59.0 °F | 84.7 °F | 0.37 in. |
| October | 51.1 °F | 73.9 °F | 2.33 in. |
| November | 42.7 °F | 60.2 °F | 4.25 in. |
| December | 37.4 °F | 52.5 °F | 8.15 in. |
| Annual | 48.4 °F | 69.6 °F | 45.06 in. |
| Average First Frost Date | Dec. 11 - Dec. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |