Proctor, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.9 °C (low) to 13.6 °C (high). Annual precipitation averages 1040.6 Millimeters. Proctor is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.8 °C | -1.4 °C | 68.33 mm |
| February | -11.3 °C | 0.2 °C | 55.37 mm |
| March | -6.1 °C | 5.2 °C | 70.1 mm |
| April | 0.4 °C | 13.3 °C | 80.77 mm |
| May | 6.8 °C | 20.2 °C | 93.73 mm |
| June | 12 °C | 24.9 °C | 109.22 mm |
| July | 14.7 °C | 27.4 °C | 117.6 mm |
| August | 13.8 °C | 26.4 °C | 102.87 mm |
| September | 9.6 °C | 22.3 °C | 88.39 mm |
| October | 3.4 °C | 14.9 °C | 102.36 mm |
| November | -1.7 °C | 7.9 °C | 71.88 mm |
| December | -7.4 °C | 1.6 °C | 80.01 mm |
| Annual | 1.9 °C | 13.6 °C | 1040.63 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°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 |