Marshfield, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.1 °C (low) to 12.1 °C (high). Annual precipitation averages 1062.5 Millimeters. Marshfield is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.7 °C | -3.3 °C | 65.02 mm |
| February | -13.9 °C | -1.3 °C | 57.91 mm |
| March | -8.5 °C | 3.6 °C | 69.6 mm |
| April | -1.2 °C | 11.3 °C | 83.57 mm |
| May | 5.4 °C | 19 °C | 95.25 mm |
| June | 10.3 °C | 23.7 °C | 113.28 mm |
| July | 13.2 °C | 26.3 °C | 117.35 mm |
| August | 11.9 °C | 25.4 °C | 99.31 mm |
| September | 7.8 °C | 21.3 °C | 93.47 mm |
| October | 1.9 °C | 13.5 °C | 104.65 mm |
| November | -3.5 °C | 6.1 °C | 76.2 mm |
| December | -9.7 °C | -0.2 °C | 86.87 mm |
| Annual | -0.1 °C | 12.1 °C | 1062.48 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |