Hartland, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33.9 °F (low) to 55.9 °F (high). Annual precipitation averages 41.1 Inches. Hartland 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 | 8.7 °F | 28.8 °F | 2.77 in. |
| February | 10.0 °F | 32.3 °F | 2.45 in. |
| March | 19.2 °F | 41.0 °F | 2.93 in. |
| April | 31.2 °F | 54.8 °F | 3.39 in. |
| May | 43.1 °F | 67.4 °F | 3.42 in. |
| June | 52.2 °F | 75.7 °F | 4.06 in. |
| July | 57.5 °F | 80.8 °F | 4.2 in. |
| August | 55.6 °F | 79.1 °F | 3.43 in. |
| September | 48.2 °F | 72.2 °F | 3.38 in. |
| October | 36.6 °F | 58.1 °F | 4.4 in. |
| November | 27.2 °F | 45.9 °F | 3.06 in. |
| December | 17.2 °F | 34.3 °F | 3.61 in. |
| Annual | 33.9 °F | 55.9 °F | 41.1 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 4b : -25°F to -20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |