Greenfield, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.7 °C (low) to 13.7 °C (high). Annual precipitation averages 1193.1 Millimeters. Greenfield 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 | -10.9 °C | -1.1 °C | 88.14 mm |
| February | -10.3 °C | 0.5 °C | 69.6 mm |
| March | -5.5 °C | 5.3 °C | 93.73 mm |
| April | 1.2 °C | 13.6 °C | 99.57 mm |
| May | 7.7 °C | 20.3 °C | 97.79 mm |
| June | 12.8 °C | 24.7 °C | 119.63 mm |
| July | 15.6 °C | 27.3 °C | 120.14 mm |
| August | 14.7 °C | 26.2 °C | 104.9 mm |
| September | 10.5 °C | 22.3 °C | 98.3 mm |
| October | 4.3 °C | 15.2 °C | 111.51 mm |
| November | -1.3 °C | 7.9 °C | 89.66 mm |
| December | -6.6 °C | 1.8 °C | 100.08 mm |
| Annual | 2.7 °C | 13.7 °C | 1193.05 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 |