Henderson, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.7 °F (low) to 55.3 °F (high). Annual precipitation averages 32.2 Inches. Henderson is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.5 °F | 23.2 °F | 0.99 in. |
| February | 9.7 °F | 28.0 °F | 0.95 in. |
| March | 22.3 °F | 40.4 °F | 1.72 in. |
| April | 35.2 °F | 56.3 °F | 2.86 in. |
| May | 47.5 °F | 69.1 °F | 4.21 in. |
| June | 58.0 °F | 78.9 °F | 5.03 in. |
| July | 62.5 °F | 82.8 °F | 3.94 in. |
| August | 59.7 °F | 80.5 °F | 4.05 in. |
| September | 51.3 °F | 73.8 °F | 3.23 in. |
| October | 38.2 °F | 59.4 °F | 2.39 in. |
| November | 25.1 °F | 42.5 °F | 1.53 in. |
| December | 12.8 °F | 28.7 °F | 1.25 in. |
| Annual | 35.7 °F | 55.3 °F | 32.15 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 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 |