Vergennes, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.4 °F (low) to 56.3 °F (high). Annual precipitation averages 36.9 Inches. Vergennes is located in USDA Plant Hardiness Zone 5a. 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 | 11.1 °F | 29.1 °F | 2.43 in. |
| February | 12.0 °F | 31.5 °F | 1.78 in. |
| March | 21.7 °F | 40.5 °F | 2.18 in. |
| April | 33.6 °F | 54.9 °F | 2.95 in. |
| May | 45.5 °F | 68.1 °F | 3.35 in. |
| June | 55.0 °F | 76.6 °F | 3.81 in. |
| July | 60.3 °F | 82.0 °F | 4.23 in. |
| August | 58.7 °F | 80.3 °F | 3.75 in. |
| September | 50.5 °F | 72.7 °F | 3.13 in. |
| October | 39.3 °F | 58.9 °F | 3.67 in. |
| November | 30.0 °F | 46.4 °F | 2.81 in. |
| December | 18.9 °F | 34.8 °F | 2.77 in. |
| Annual | 36.4 °F | 56.3 °F | 36.86 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |