Poestenkill, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.3 °C (low) to 14.4 °C (high). Annual precipitation averages 1128.3 Millimeters. Poestenkill is located in USDA Plant Hardiness Zone 6a. 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 | -9.7 °C | -0.2 °C | 78.74 mm |
| February | -9 °C | 1.4 °C | 60.96 mm |
| March | -4.3 °C | 6.2 °C | 78.23 mm |
| April | 1.9 °C | 14.2 °C | 87.63 mm |
| May | 8.2 °C | 20.7 °C | 93.22 mm |
| June | 13.3 °C | 25.2 °C | 119.89 mm |
| July | 15.7 °C | 27.9 °C | 116.59 mm |
| August | 15.1 °C | 26.8 °C | 109.98 mm |
| September | 10.7 °C | 22.9 °C | 102.87 mm |
| October | 4.6 °C | 15.8 °C | 111.51 mm |
| November | -0.7 °C | 9 °C | 80.01 mm |
| December | -5.7 °C | 2.8 °C | 88.65 mm |
| Annual | 3.3 °C | 14.4 °C | 1128.28 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |