Winthrop, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.7 °F (low) to 54.5 °F (high). Annual precipitation averages 40 Inches. Winthrop is located in USDA Plant Hardiness Zone 4b. 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 | 8.1 °F | 25.4 °F | 2.73 in. |
| February | 9.6 °F | 28.2 °F | 2.2 in. |
| March | 20.1 °F | 37.9 °F | 2.47 in. |
| April | 33.8 °F | 53.3 °F | 3.32 in. |
| May | 46.0 °F | 67.6 °F | 3.31 in. |
| June | 55.5 °F | 75.8 °F | 4.12 in. |
| July | 60.2 °F | 80.4 °F | 3.95 in. |
| August | 58.3 °F | 78.7 °F | 3.49 in. |
| September | 50.3 °F | 71.5 °F | 3.88 in. |
| October | 39.7 °F | 58.0 °F | 4.29 in. |
| November | 29.1 °F | 44.9 °F | 3.24 in. |
| December | 17.2 °F | 32.3 °F | 2.98 in. |
| Annual | 35.7 °F | 54.5 °F | 39.98 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |