Wilton, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.4 °C (low) to 14.5 °C (high). Annual precipitation averages 1153.4 Millimeters. Wilton is located in USDA Plant Hardiness Zone 5b. 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 | -10.1 °C | -0.3 °C | 84.07 mm |
| February | -9.4 °C | 1.3 °C | 66.55 mm |
| March | -4.4 °C | 6.3 °C | 86.61 mm |
| April | 2.1 °C | 14.3 °C | 95.76 mm |
| May | 8.5 °C | 21.1 °C | 93.47 mm |
| June | 13.6 °C | 25.6 °C | 116.08 mm |
| July | 16.2 °C | 28.1 °C | 122.94 mm |
| August | 15.3 °C | 27.1 °C | 102.62 mm |
| September | 11.1 °C | 23.1 °C | 92.2 mm |
| October | 4.8 °C | 15.9 °C | 110.74 mm |
| November | -0.7 °C | 8.8 °C | 85.09 mm |
| December | -5.8 °C | 2.6 °C | 97.28 mm |
| Annual | 3.4 °C | 14.5 °C | 1153.41 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 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |