Hempstead, New York has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8 °C (low) to 17 °C (high). Annual precipitation averages 1240.3 Millimeters. Hempstead is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.3 °C | 4.4 °C | 96.52 mm |
| February | -2.7 °C | 5.7 °C | 77.47 mm |
| March | 0.7 °C | 9.4 °C | 112.01 mm |
| April | 5.8 °C | 15.7 °C | 102.87 mm |
| May | 11 °C | 21.1 °C | 100.33 mm |
| June | 16.4 °C | 26.1 °C | 112.01 mm |
| July | 19.7 °C | 29.3 °C | 108.71 mm |
| August | 19.1 °C | 28.4 °C | 113.03 mm |
| September | 15.4 °C | 24.8 °C | 103.38 mm |
| October | 9.4 °C | 18.6 °C | 119.13 mm |
| November | 4.1 °C | 12.6 °C | 85.6 mm |
| December | -0.1 °C | 7.4 °C | 109.22 mm |
| Annual | 8 °C | 17 °C | 1240.28 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |