Southport, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.7 °F (low) to 58.9 °F (high). Annual precipitation averages 36.9 Inches. Southport is located in USDA Plant Hardiness Zone 6a. 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 | 15.4 °F | 33.4 °F | 2.11 in. |
| February | 16.0 °F | 35.9 °F | 1.85 in. |
| March | 23.2 °F | 44.4 °F | 2.74 in. |
| April | 33.3 °F | 58.0 °F | 3.32 in. |
| May | 44.4 °F | 70.2 °F | 3.14 in. |
| June | 53.6 °F | 78.3 °F | 4.09 in. |
| July | 57.8 °F | 82.9 °F | 3.87 in. |
| August | 56.6 °F | 81.3 °F | 3.58 in. |
| September | 49.6 °F | 74.3 °F | 3.65 in. |
| October | 38.5 °F | 61.2 °F | 3.53 in. |
| November | 29.6 °F | 48.8 °F | 2.56 in. |
| December | 22.2 °F | 38.0 °F | 2.46 in. |
| Annual | 36.7 °F | 58.9 °F | 36.9 in. |
| 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |