San Bernardino, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 52.4 °F (low) to 79.7 °F (high). Annual precipitation averages 12.2 Inches. San Bernardino is located in USDA Plant Hardiness Zone 10a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 43.0 °F | 67.2 °F | 2.66 in. |
| February | 44.0 °F | 67.5 °F | 2.96 in. |
| March | 46.7 °F | 71.0 °F | 1.99 in. |
| April | 49.4 °F | 75.6 °F | 0.74 in. |
| May | 54.2 °F | 80.5 °F | 0.31 in. |
| June | 58.3 °F | 87.9 °F | 0.08 in. |
| July | 63.3 °F | 94.9 °F | 0.06 in. |
| August | 64.2 °F | 96.0 °F | 0.06 in. |
| September | 61.5 °F | 92.5 °F | 0.15 in. |
| October | 54.7 °F | 82.9 °F | 0.52 in. |
| November | 47.3 °F | 74.1 °F | 0.75 in. |
| December | 42.1 °F | 66.4 °F | 1.89 in. |
| Annual | 52.4 °F | 79.7 °F | 12.17 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 40-50 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 | Csa - Hot-Summer Mediterranean Climate |