Mission Viejo, California has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 53.3 °F (low) to 74.9 °F (high). Annual precipitation averages 15 Inches. Mission Viejo is located in USDA Plant Hardiness Zone 10b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 46.4 °F | 67.8 °F | 3.03 in. |
| February | 46.5 °F | 67.6 °F | 3.72 in. |
| March | 48.1 °F | 69.3 °F | 2.21 in. |
| April | 50.1 °F | 71.8 °F | 0.94 in. |
| May | 54.4 °F | 73.4 °F | 0.32 in. |
| June | 57.9 °F | 77.4 °F | 0.21 in. |
| July | 61.4 °F | 83.0 °F | 0.11 in. |
| August | 62.0 °F | 84.6 °F | 0.03 in. |
| September | 60.5 °F | 84.1 °F | 0.13 in. |
| October | 56.1 °F | 79.3 °F | 0.69 in. |
| November | 50.1 °F | 73.0 °F | 1.06 in. |
| December | 45.8 °F | 67.1 °F | 2.58 in. |
| Annual | 53.3 °F | 74.9 °F | 15.03 in. |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10b : 35°F to 30°F |
| Plant Hardiness Zone - 2012 | Zone 10a : 30°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |