Fort Johnson, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.5 °F (low) to 57.8 °F (high). Annual precipitation averages 42.4 Inches. Fort Johnson is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.6 °F | 31.1 °F | 3.16 in. |
| February | 15.9 °F | 33.9 °F | 2.5 in. |
| March | 24.0 °F | 42.4 °F | 3.29 in. |
| April | 36.0 °F | 57.0 °F | 3.44 in. |
| May | 47.6 °F | 69.5 °F | 3.47 in. |
| June | 56.3 °F | 77.6 °F | 4.56 in. |
| July | 61.6 °F | 82.1 °F | 4.29 in. |
| August | 59.7 °F | 80.7 °F | 3.86 in. |
| September | 52.4 °F | 73.5 °F | 3.48 in. |
| October | 41.0 °F | 61.4 °F | 3.86 in. |
| November | 30.7 °F | 47.5 °F | 3.27 in. |
| December | 21.9 °F | 36.3 °F | 3.19 in. |
| Annual | 38.5 °F | 57.8 °F | 42.37 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |