Knox, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.9 °C (low) to 13.4 °C (high). Annual precipitation averages 1075.4 Millimeters. Knox 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 | -11.1 °C | -1.1 °C | 68.33 mm |
| February | -10.6 °C | 0.4 °C | 61.47 mm |
| March | -6.6 °C | 4.7 °C | 88.65 mm |
| April | 0.3 °C | 12.8 °C | 86.61 mm |
| May | 7.1 °C | 19.8 °C | 90.93 mm |
| June | 11.9 °C | 24.2 °C | 111.25 mm |
| July | 14.3 °C | 26.8 °C | 105.92 mm |
| August | 13.4 °C | 25.9 °C | 97.79 mm |
| September | 9.3 °C | 22.2 °C | 90.68 mm |
| October | 3.1 °C | 14.9 °C | 114.55 mm |
| November | -1.9 °C | 7.9 °C | 72.9 mm |
| December | -6.9 °C | 2.2 °C | 86.36 mm |
| Annual | 1.9 °C | 13.4 °C | 1075.44 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| 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 |