Henderson, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2 °C (low) to 12.9 °C (high). Annual precipitation averages 816.6 Millimeters. 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 | -14.7 °C | -4.9 °C | 25.15 mm |
| February | -12.4 °C | -2.2 °C | 24.13 mm |
| March | -5.4 °C | 4.7 °C | 43.69 mm |
| April | 1.8 °C | 13.5 °C | 72.64 mm |
| May | 8.6 °C | 20.6 °C | 106.93 mm |
| June | 14.4 °C | 26.1 °C | 127.76 mm |
| July | 16.9 °C | 28.2 °C | 100.08 mm |
| August | 15.4 °C | 26.9 °C | 102.87 mm |
| September | 10.7 °C | 23.2 °C | 82.04 mm |
| October | 3.4 °C | 15.2 °C | 60.71 mm |
| November | -3.8 °C | 5.8 °C | 38.86 mm |
| December | -10.7 °C | -1.8 °C | 31.75 mm |
| Annual | 2 °C | 12.9 °C | 816.61 mm |
| 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 : -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 |