Penn Yan, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.2 °C (low) to 14.4 °C (high). Annual precipitation averages 890.3 Millimeters. Penn Yan 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.1 °C | 0.5 °C | 55.88 mm |
| February | -7.6 °C | 1.6 °C | 48.77 mm |
| March | -3.8 °C | 6.2 °C | 65.02 mm |
| April | 1.9 °C | 13.7 °C | 69.6 mm |
| May | 8.4 °C | 20.6 °C | 77.47 mm |
| June | 13.7 °C | 25.1 °C | 87.63 mm |
| July | 16.3 °C | 27.4 °C | 100.33 mm |
| August | 15.5 °C | 26.6 °C | 84.07 mm |
| September | 11.6 °C | 23.1 °C | 82.3 mm |
| October | 5.9 °C | 15.9 °C | 88.39 mm |
| November | 0.5 °C | 9.3 °C | 70.36 mm |
| December | -4.3 °C | 3.3 °C | 60.45 mm |
| Annual | 4.2 °C | 14.4 °C | 890.27 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| 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 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |