Wilbraham, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.9 °C (low) to 15.4 °C (high). Annual precipitation averages 1201.7 Millimeters. Wilbraham 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 | -8.7 °C | 1.3 °C | 86.11 mm |
| February | -8.1 °C | 2.9 °C | 76.96 mm |
| March | -3.3 °C | 7.4 °C | 100.84 mm |
| April | 2.5 °C | 14.9 °C | 96.77 mm |
| May | 8.3 °C | 21.1 °C | 90.93 mm |
| June | 13.4 °C | 25.7 °C | 109.98 mm |
| July | 16.5 °C | 28.7 °C | 102.11 mm |
| August | 15.6 °C | 27.8 °C | 106.43 mm |
| September | 11.3 °C | 23.8 °C | 113.28 mm |
| October | 4.9 °C | 16.9 °C | 121.67 mm |
| November | -0.4 °C | 10.2 °C | 89.92 mm |
| December | -5.1 °C | 4.3 °C | 106.68 mm |
| Annual | 3.9 °C | 15.4 °C | 1201.68 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 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |