Glenville, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.6 °C (low) to 13.7 °C (high). Annual precipitation averages 1152.9 Millimeters. Glenville is located in USDA Plant Hardiness Zone 5b. 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 | -10.7 °C | -1.1 °C | 80.26 mm |
| February | -9.9 °C | 0.4 °C | 67.56 mm |
| March | -5.3 °C | 5.3 °C | 89.41 mm |
| April | 1.1 °C | 13.3 °C | 93.22 mm |
| May | 7.7 °C | 20.2 °C | 95.5 mm |
| June | 12.7 °C | 24.7 °C | 116.59 mm |
| July | 15.3 °C | 27.4 °C | 115.57 mm |
| August | 14.4 °C | 26.4 °C | 109.98 mm |
| September | 10.2 °C | 22.4 °C | 97.03 mm |
| October | 3.9 °C | 15.2 °C | 113.03 mm |
| November | -1.6 °C | 8.1 °C | 81.03 mm |
| December | -6.6 °C | 1.9 °C | 93.73 mm |
| Annual | 2.6 °C | 13.7 °C | 1152.91 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 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |