McNary, Arizona has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 1 °C (low) to 17.4 °C (high). Annual precipitation averages 631.9 Millimeters. McNary is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.4 °C | 7.4 °C | 60.45 mm |
| February | -6 °C | 8.9 °C | 54.86 mm |
| March | -3.8 °C | 12.1 °C | 57.66 mm |
| April | -1.4 °C | 16.1 °C | 27.43 mm |
| May | 3 °C | 21.1 °C | 18.03 mm |
| June | 8 °C | 27.1 °C | 14.73 mm |
| July | 10.9 °C | 27.6 °C | 90.93 mm |
| August | 10.5 °C | 26 °C | 104.39 mm |
| September | 7.3 °C | 23.7 °C | 54.86 mm |
| October | 1.7 °C | 18.6 °C | 43.94 mm |
| November | -3.7 °C | 12.4 °C | 40.39 mm |
| December | -7.3 °C | 7.6 °C | 64.26 mm |
| Annual | 1 °C | 17.4 °C | 631.93 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |