Horseheads, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.7 °C (low) to 14.9 °C (high). Annual precipitation averages 929.1 Millimeters. Horseheads is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.3 °C | 0.7 °C | 54.86 mm |
| February | -8.8 °C | 2.2 °C | 46.23 mm |
| March | -4.8 °C | 6.9 °C | 68.07 mm |
| April | 0.8 °C | 14.4 °C | 83.06 mm |
| May | 6.9 °C | 21.2 °C | 78.74 mm |
| June | 12.1 °C | 25.7 °C | 99.57 mm |
| July | 14.4 °C | 28.2 °C | 93.22 mm |
| August | 13.7 °C | 27.4 °C | 90.17 mm |
| September | 9.8 °C | 23.4 °C | 94.74 mm |
| October | 3.7 °C | 16.2 °C | 90.17 mm |
| November | -1.3 °C | 9.3 °C | 67.06 mm |
| December | -5.4 °C | 3.3 °C | 63.25 mm |
| Annual | 2.7 °C | 14.9 °C | 929.14 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |