Brattleboro, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 36.1 °F (low) to 58.5 °F (high). Annual precipitation averages 49.5 Inches. Brattleboro 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 | 12.3 °F | 32.1 °F | 3.57 in. |
| February | 13.5 °F | 35.6 °F | 3.18 in. |
| March | 22.6 °F | 43.8 °F | 3.82 in. |
| April | 33.3 °F | 57.2 °F | 3.89 in. |
| May | 44.4 °F | 69.4 °F | 3.94 in. |
| June | 54.1 °F | 78.1 °F | 4.58 in. |
| July | 59.2 °F | 83.2 °F | 4.09 in. |
| August | 57.4 °F | 81.7 °F | 4.35 in. |
| September | 49.4 °F | 74.3 °F | 4.56 in. |
| October | 38.1 °F | 60.9 °F | 5.29 in. |
| November | 29.0 °F | 48.5 °F | 3.9 in. |
| December | 19.6 °F | 37.3 °F | 4.34 in. |
| Annual | 36.1 °F | 58.5 °F | 49.51 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |