Clark Mills, 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 13.8 °C (high). Annual precipitation averages 1168.6 Millimeters. Clark Mills is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.9 °C | -1.1 °C | 78.74 mm |
| February | -9.5 °C | 0.3 °C | 72.14 mm |
| March | -4.8 °C | 4.9 °C | 82.55 mm |
| April | 1.7 °C | 13.2 °C | 94.23 mm |
| May | 7.9 °C | 20.6 °C | 98.3 mm |
| June | 13.3 °C | 25.1 °C | 123.44 mm |
| July | 15.9 °C | 27.7 °C | 104.39 mm |
| August | 15.2 °C | 26.7 °C | 103.63 mm |
| September | 11.1 °C | 22.7 °C | 102.11 mm |
| October | 5.2 °C | 15.4 °C | 119.38 mm |
| November | -0.2 °C | 8.4 °C | 95.5 mm |
| December | -5.7 °C | 2.1 °C | 94.23 mm |
| Annual | 3.4 °C | 13.8 °C | 1168.64 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |