Gill, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.1 °C (low) to 14.1 °C (high). Annual precipitation averages 1222.5 Millimeters. Gill is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.1 °C | -0.2 °C | 90.42 mm |
| February | -10.4 °C | 1.5 °C | 78.49 mm |
| March | -5.6 °C | 6.2 °C | 94.74 mm |
| April | 0.6 °C | 13.4 °C | 98.55 mm |
| May | 6.8 °C | 20 °C | 93.98 mm |
| June | 12 °C | 24.8 °C | 109.22 mm |
| July | 15 °C | 27.8 °C | 109.98 mm |
| August | 13.8 °C | 26.8 °C | 108.97 mm |
| September | 9.4 °C | 22.6 °C | 113.54 mm |
| October | 3.2 °C | 15.3 °C | 125.73 mm |
| November | -1.9 °C | 8.7 °C | 93.98 mm |
| December | -7.2 °C | 2.7 °C | 104.9 mm |
| Annual | 2.1 °C | 14.1 °C | 1222.5 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°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 |