Lebanon, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2 °C (low) to 13.1 °C (high). Annual precipitation averages 1178.3 Millimeters. Lebanon is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.9 °C | -1.2 °C | 81.53 mm |
| February | -10.1 °C | 0.1 °C | 71.37 mm |
| March | -6.2 °C | 4.7 °C | 91.44 mm |
| April | 0.4 °C | 12.3 °C | 97.03 mm |
| May | 6.7 °C | 19.4 °C | 99.82 mm |
| June | 11.6 °C | 24.2 °C | 119.13 mm |
| July | 14.1 °C | 26.4 °C | 113.28 mm |
| August | 13.3 °C | 25.4 °C | 111 mm |
| September | 9.4 °C | 21.8 °C | 103.63 mm |
| October | 3.6 °C | 14.6 °C | 106.93 mm |
| November | -1.7 °C | 7.7 °C | 90.42 mm |
| December | -6.6 °C | 1.6 °C | 92.71 mm |
| Annual | 2 °C | 13.1 °C | 1178.29 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 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 |