Washington Park, Arizona has a Hot-Summer Mediterranean Climate climate (Köppen classification: Csa). Average annual temperatures range from 3.3 °C (low) to 19.5 °C (high). Annual precipitation averages 719.6 Millimeters. Washington Park is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.3 °C | 9.8 °C | 98.81 mm |
| February | -3.6 °C | 10.9 °C | 82.3 mm |
| March | -1.6 °C | 14.1 °C | 78.74 mm |
| April | 0.9 °C | 17.7 °C | 26.16 mm |
| May | 4.6 °C | 22.7 °C | 22.1 mm |
| June | 9.1 °C | 28.8 °C | 8.89 mm |
| July | 13.4 °C | 30.3 °C | 78.23 mm |
| August | 12.9 °C | 28.9 °C | 91.19 mm |
| September | 9.6 °C | 26.2 °C | 57.4 mm |
| October | 3.8 °C | 20.8 °C | 38.86 mm |
| November | -1.1 °C | 14.5 °C | 53.34 mm |
| December | -4.4 °C | 9.6 °C | 83.57 mm |
| Annual | 3.3 °C | 19.5 °C | 719.59 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Csa - Hot-Summer Mediterranean Climate |