Delanson, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.3 °C (low) to 14 °C (high). Annual precipitation averages 1033 Millimeters. Delanson 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 | -10.7 °C | -0.8 °C | 64.77 mm |
| February | -10.1 °C | 0.8 °C | 59.44 mm |
| March | -5.7 °C | 5.6 °C | 78.23 mm |
| April | 0.8 °C | 13.7 °C | 85.85 mm |
| May | 7.3 °C | 20.5 °C | 93.22 mm |
| June | 12.2 °C | 24.9 °C | 106.17 mm |
| July | 14.9 °C | 27.5 °C | 106.17 mm |
| August | 13.9 °C | 26.7 °C | 100.08 mm |
| September | 9.8 °C | 22.8 °C | 86.11 mm |
| October | 3.7 °C | 15.6 °C | 102.87 mm |
| November | -1.7 °C | 8.5 °C | 69.34 mm |
| December | -6.7 °C | 2.2 °C | 80.77 mm |
| Annual | 2.3 °C | 14 °C | 1033.02 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 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |