San Clemente, California has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 11.7 °C (low) to 21.8 °C (high). Annual precipitation averages 337.6 Millimeters. San Clemente is located in USDA Plant Hardiness Zone 10b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.1 °C | 19.3 °C | 66.04 mm |
| February | 8.1 °C | 19.1 °C | 82.04 mm |
| March | 8.6 °C | 19.7 °C | 50.55 mm |
| April | 9.7 °C | 19.7 °C | 22.35 mm |
| May | 12.1 °C | 20.6 °C | 8.64 mm |
| June | 14.2 °C | 22.1 °C | 4.06 mm |
| July | 16.1 °C | 25 °C | 2.03 mm |
| August | 16.4 °C | 25.7 °C | 0.76 mm |
| September | 15.6 °C | 25.4 °C | 3.05 mm |
| October | 13.2 °C | 23.7 °C | 14.99 mm |
| November | 10.1 °C | 21.8 °C | 25.65 mm |
| December | 7.8 °C | 18.9 °C | 57.4 mm |
| Annual | 11.7 °C | 21.8 °C | 337.56 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10b : 1.7°C to 4.4°C |
| Plant Hardiness Zone - 2012 | Zone 10a : -1.1°C to 1.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |