Johnsburg, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2.1 °C (low) to 9.3 °C (high). Annual precipitation averages 1400.8 Millimeters. Johnsburg is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.5 °C | -4.8 °C | 121.41 mm |
| February | -15 °C | -3.6 °C | 88.9 mm |
| March | -10.8 °C | 0.8 °C | 125.73 mm |
| April | -3.4 °C | 8.6 °C | 115.82 mm |
| May | 2.8 °C | 15.6 °C | 115.82 mm |
| June | 7.9 °C | 20.1 °C | 132.33 mm |
| July | 10.4 °C | 22.4 °C | 111.76 mm |
| August | 9.6 °C | 21.6 °C | 107.7 mm |
| September | 5.6 °C | 18.1 °C | 110.24 mm |
| October | -0.2 °C | 11.1 °C | 133.35 mm |
| November | -5.4 °C | 3.8 °C | 109.73 mm |
| December | -10.9 °C | -1.9 °C | 128.02 mm |
| Annual | -2.1 °C | 9.3 °C | 1400.81 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |