Irasburg, Vermont has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.3 °F (low) to 52.4 °F (high). Annual precipitation averages 47.8 Inches. Irasburg 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.0 °F | 24.3 °F | 3.31 in. |
| February | 5.1 °F | 27.7 °F | 2.86 in. |
| March | 15.5 °F | 36.8 °F | 3.18 in. |
| April | 30.3 °F | 51.0 °F | 3.75 in. |
| May | 41.8 °F | 64.7 °F | 4.24 in. |
| June | 50.6 °F | 73.2 °F | 4.74 in. |
| July | 55.2 °F | 77.8 °F | 4.76 in. |
| August | 53.4 °F | 76.2 °F | 4.49 in. |
| September | 46.3 °F | 68.8 °F | 3.81 in. |
| October | 34.7 °F | 55.3 °F | 4.86 in. |
| November | 24.8 °F | 42.2 °F | 3.83 in. |
| December | 13.8 °F | 30.7 °F | 3.95 in. |
| Annual | 31.3 °F | 52.4 °F | 47.78 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |