Three Mile Bay, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.2 °C (low) to 12.3 °C (high). Annual precipitation averages 1021.1 Millimeters. Three Mile Bay is located in USDA Plant Hardiness Zone 5a. 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 | -11.1 °C | -2.2 °C | 86.61 mm |
| February | -10.7 °C | -1.2 °C | 66.55 mm |
| March | -5.5 °C | 3.4 °C | 68.58 mm |
| April | 1.5 °C | 11.1 °C | 85.34 mm |
| May | 7.9 °C | 17.9 °C | 81.79 mm |
| June | 13.4 °C | 22.9 °C | 86.61 mm |
| July | 16.6 °C | 25.7 °C | 78.74 mm |
| August | 15.8 °C | 25.3 °C | 83.57 mm |
| September | 11.6 °C | 21.4 °C | 90.93 mm |
| October | 5.7 °C | 14.3 °C | 108.46 mm |
| November | -0.2 °C | 7.8 °C | 93.73 mm |
| December | -6.2 °C | 1.4 °C | 90.17 mm |
| Annual | 3.2 °C | 12.3 °C | 1021.08 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 5a : -28.9°C to -26.1°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 |