Morristown, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.6 °C (low) to 12.4 °C (high). Annual precipitation averages 987.6 Millimeters. Morristown is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.2 °C | -2.9 °C | 79.5 mm |
| February | -11.6 °C | -1.6 °C | 60.45 mm |
| March | -6 °C | 3.4 °C | 64.52 mm |
| April | 1.4 °C | 11.4 °C | 84.33 mm |
| May | 7.8 °C | 18.8 °C | 82.55 mm |
| June | 13.2 °C | 23.6 °C | 89.15 mm |
| July | 15.9 °C | 26.4 °C | 90.68 mm |
| August | 14.9 °C | 25.8 °C | 83.06 mm |
| September | 10.7 °C | 21.8 °C | 87.88 mm |
| October | 4.8 °C | 14.2 °C | 103.38 mm |
| November | -0.9 °C | 7.5 °C | 82.8 mm |
| December | -7.2 °C | 0.7 °C | 79.25 mm |
| Annual | 2.6 °C | 12.4 °C | 987.55 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |