San Carlos, Arizona has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 9.7 °C (low) to 27.8 °C (high). Annual precipitation averages 296.2 Millimeters. San Carlos is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.1 °C | 16.8 °C | 38.1 mm |
| February | 1.6 °C | 19.2 °C | 32.51 mm |
| March | 4.2 °C | 22.9 °C | 25.65 mm |
| April | 7.9 °C | 27.1 °C | 6.6 mm |
| May | 11.9 °C | 32.6 °C | 7.87 mm |
| June | 18 °C | 37.8 °C | 4.83 mm |
| July | 21.9 °C | 38.2 °C | 44.2 mm |
| August | 21.7 °C | 37.1 °C | 43.43 mm |
| September | 17.2 °C | 34.4 °C | 23.62 mm |
| October | 9.9 °C | 29.1 °C | 21.08 mm |
| November | 3.3 °C | 22.3 °C | 17.02 mm |
| December | -0.6 °C | 16.2 °C | 31.24 mm |
| Annual | 9.7 °C | 27.8 °C | 296.15 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |