Hillside, New York has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.1 °C (low) to 16.1 °C (high). Annual precipitation averages 1241.3 Millimeters. Hillside is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.4 °C | 2 °C | 89.15 mm |
| February | -7.6 °C | 3.6 °C | 70.87 mm |
| March | -3.2 °C | 8.4 °C | 96.01 mm |
| April | 2.9 °C | 15.9 °C | 99.31 mm |
| May | 8.6 °C | 22.1 °C | 97.28 mm |
| June | 13.7 °C | 26.7 °C | 111.25 mm |
| July | 16.4 °C | 29.4 °C | 121.92 mm |
| August | 15.6 °C | 28.3 °C | 111 mm |
| September | 11.3 °C | 24.2 °C | 123.7 mm |
| October | 5.2 °C | 17.3 °C | 123.44 mm |
| November | -0.3 °C | 10.7 °C | 90.93 mm |
| December | -4.9 °C | 4.6 °C | 106.43 mm |
| Annual | 4.1 °C | 16.1 °C | 1241.29 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |