Randolph, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.5 °C (low) to 13.2 °C (high). Annual precipitation averages 1120.7 Millimeters. Randolph is located in USDA Plant Hardiness Zone 5a. 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 | -13.4 °C | -1.9 °C | 77.98 mm |
| February | -12.9 °C | -0.2 °C | 68.58 mm |
| March | -7.8 °C | 4.6 °C | 87.12 mm |
| April | -1.1 °C | 12.4 °C | 88.14 mm |
| May | 5.4 °C | 20 °C | 87.38 mm |
| June | 10.5 °C | 24.5 °C | 116.33 mm |
| July | 13.4 °C | 27.2 °C | 115.06 mm |
| August | 12.5 °C | 26 °C | 104.14 mm |
| September | 8.4 °C | 22.2 °C | 90.17 mm |
| October | 2.3 °C | 14.7 °C | 105.41 mm |
| November | -3 °C | 7.4 °C | 82.8 mm |
| December | -8.8 °C | 0.9 °C | 97.54 mm |
| Annual | 0.5 °C | 13.2 °C | 1120.65 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 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |