Wallkill, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.4 °C (low) to 16.1 °C (high). Annual precipitation averages 1168.4 Millimeters. Wallkill is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.1 °C | 2.1 °C | 82.55 mm |
| February | -7.2 °C | 3.7 °C | 67.06 mm |
| March | -2.7 °C | 8.3 °C | 93.47 mm |
| April | 3.3 °C | 15.8 °C | 92.71 mm |
| May | 8.9 °C | 21.7 °C | 92.46 mm |
| June | 13.9 °C | 26.4 °C | 114.81 mm |
| July | 16.7 °C | 29.2 °C | 109.47 mm |
| August | 15.8 °C | 28.3 °C | 108.97 mm |
| September | 11.6 °C | 24.3 °C | 112.52 mm |
| October | 5.3 °C | 17.5 °C | 108.97 mm |
| November | -0.1 °C | 10.8 °C | 86.11 mm |
| December | -4.7 °C | 4.7 °C | 99.31 mm |
| Annual | 4.4 °C | 16.1 °C | 1168.41 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |