Oroville, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 49.6 °F (low) to 74.9 °F (high). Annual precipitation averages 29.5 Inches. Oroville is located in USDA Plant Hardiness Zone 9b. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.8 °F | 55.6 °F | 5.95 in. |
| February | 41.1 °F | 60.7 °F | 5.0 in. |
| March | 43.7 °F | 65.7 °F | 4.26 in. |
| April | 46.8 °F | 71.7 °F | 2.28 in. |
| May | 52.8 °F | 80.4 °F | 1.42 in. |
| June | 58.7 °F | 88.8 °F | 0.42 in. |
| July | 62.8 °F | 94.7 °F | 0.02 in. |
| August | 60.9 °F | 93.3 °F | 0.07 in. |
| September | 57.5 °F | 88.8 °F | 0.2 in. |
| October | 50.7 °F | 78.6 °F | 1.43 in. |
| November | 42.8 °F | 64.5 °F | 2.94 in. |
| December | 38.5 °F | 55.5 °F | 5.48 in. |
| Annual | 49.6 °F | 74.9 °F | 29.47 in. |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9b : 25°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 9b : 25°F to 20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |