Guilderland, New York has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4 °C (low) to 14.6 °C (high). Annual precipitation averages 1088.9 Millimeters. Guilderland 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 | -9.2 °C | -0.1 °C | 69.09 mm |
| February | -8.5 °C | 1.6 °C | 61.72 mm |
| March | -3.8 °C | 6.5 °C | 84.58 mm |
| April | 2.6 °C | 14.3 °C | 88.39 mm |
| May | 8.9 °C | 20.9 °C | 91.95 mm |
| June | 14.1 °C | 25.5 °C | 115.06 mm |
| July | 16.7 °C | 28.1 °C | 115.57 mm |
| August | 15.8 °C | 27.1 °C | 100.58 mm |
| September | 11.4 °C | 23.1 °C | 90.93 mm |
| October | 5.1 °C | 15.9 °C | 111.51 mm |
| November | -0.4 °C | 9.1 °C | 70.1 mm |
| December | -5.3 °C | 2.9 °C | 89.41 mm |
| Annual | 4 °C | 14.6 °C | 1088.89 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |