Hermon, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.7 °C (low) to 12.5 °C (high). Annual precipitation averages 1063 Millimeters. Hermon is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.3 °C | -3 °C | 78.23 mm |
| February | -12.7 °C | -1.6 °C | 60.71 mm |
| March | -7.1 °C | 3.6 °C | 69.34 mm |
| April | 0.6 °C | 11.8 °C | 87.38 mm |
| May | 7.3 °C | 19.3 °C | 90.42 mm |
| June | 12.6 °C | 23.9 °C | 105.66 mm |
| July | 15.2 °C | 26.4 °C | 99.06 mm |
| August | 14.1 °C | 25.7 °C | 89.66 mm |
| September | 9.7 °C | 21.7 °C | 95.25 mm |
| October | 3.8 °C | 14.2 °C | 115.57 mm |
| November | -1.9 °C | 7.3 °C | 90.42 mm |
| December | -8.4 °C | 0.5 °C | 81.28 mm |
| Annual | 1.7 °C | 12.5 °C | 1062.98 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |