Irondequoit, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.9 °C (low) to 13.8 °C (high). Annual precipitation averages 877.6 Millimeters. Irondequoit is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.2 °C | 0.6 °C | 63.5 mm |
| February | -7 °C | 1.3 °C | 51.05 mm |
| March | -3.3 °C | 5.4 °C | 62.74 mm |
| April | 2.5 °C | 12.2 °C | 74.68 mm |
| May | 8.3 °C | 19 °C | 73.15 mm |
| June | 14.1 °C | 23.8 °C | 81.03 mm |
| July | 17.5 °C | 26.6 °C | 85.09 mm |
| August | 16.8 °C | 25.9 °C | 80.52 mm |
| September | 12.9 °C | 22.4 °C | 80.52 mm |
| October | 6.8 °C | 15.7 °C | 87.38 mm |
| November | 1.3 °C | 9.3 °C | 69.85 mm |
| December | -3.6 °C | 3.5 °C | 68.07 mm |
| Annual | 4.9 °C | 13.8 °C | 877.58 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |