South Pasadena, California has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 53.6 °F (low) to 77.8 °F (high). Annual precipitation averages 18.5 Inches. South Pasadena is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 45.9 °F | 68.6 °F | 4.17 in. |
| February | 46.5 °F | 68.8 °F | 4.75 in. |
| March | 48.6 °F | 71.1 °F | 3.2 in. |
| April | 51.1 °F | 75.2 °F | 1.01 in. |
| May | 55.0 °F | 77.2 °F | 0.47 in. |
| June | 58.5 °F | 82.0 °F | 0.13 in. |
| July | 62.3 °F | 87.4 °F | 0.04 in. |
| August | 63.0 °F | 89.8 °F | 0.02 in. |
| September | 61.6 °F | 88.8 °F | 0.17 in. |
| October | 56.6 °F | 82.6 °F | 0.67 in. |
| November | 49.7 °F | 74.7 °F | 0.89 in. |
| December | 44.9 °F | 67.9 °F | 2.95 in. |
| Annual | 53.6 °F | 77.8 °F | 18.47 in. |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10a : 30°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 10a : 30°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |