Middlebury, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.3 °F (low) to 56.2 °F (high). Annual precipitation averages 38.8 Inches. Middlebury 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.3 °F | 28.8 °F | 2.43 in. |
| February | 11.2 °F | 31.5 °F | 1.9 in. |
| March | 20.6 °F | 40.6 °F | 2.29 in. |
| April | 32.5 °F | 55.2 °F | 3.14 in. |
| May | 44.3 °F | 68.1 °F | 3.57 in. |
| June | 53.6 °F | 76.8 °F | 4.13 in. |
| July | 58.7 °F | 81.6 °F | 4.22 in. |
| August | 57.1 °F | 79.9 °F | 3.83 in. |
| September | 49.4 °F | 72.5 °F | 3.36 in. |
| October | 38.2 °F | 58.7 °F | 4.0 in. |
| November | 29.2 °F | 46.1 °F | 2.9 in. |
| December | 18.1 °F | 34.5 °F | 3.04 in. |
| Annual | 35.3 °F | 56.2 °F | 38.81 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| 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 |