San Luis, Arizona has a Hot Desert Climate climate (Köppen classification: BWh). Average annual temperatures range from 14.6 °C (low) to 30.9 °C (high). Annual precipitation averages 76.7 Millimeters. San Luis is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.8 °C | 20.9 °C | 9.91 mm |
| February | 7.2 °C | 22.8 °C | 11.43 mm |
| March | 9.8 °C | 26.3 °C | 8.38 mm |
| April | 12.4 °C | 29.6 °C | 3.05 mm |
| May | 15.9 °C | 33.9 °C | 1.27 mm |
| June | 20.3 °C | 38.8 °C | 0.51 mm |
| July | 25.3 °C | 41 °C | 5.84 mm |
| August | 26 °C | 41 °C | 8.13 mm |
| September | 22.6 °C | 38.5 °C | 9.4 mm |
| October | 15.7 °C | 32.6 °C | 3.3 mm |
| November | 9.4 °C | 25.6 °C | 5.33 mm |
| December | 5.3 °C | 19.9 °C | 10.16 mm |
| Annual | 14.6 °C | 30.9 °C | 76.71 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 10a : -1.1°C to 1.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | BWh - Hot Desert Climate |