Wetonka, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 32.1 °F (low) to 54.2 °F (high). Annual precipitation averages 22.1 Inches. Wetonka is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.5 °F | 21.6 °F | 0.49 in. |
| February | 6.7 °F | 26.8 °F | 0.61 in. |
| March | 18.6 °F | 39.3 °F | 0.98 in. |
| April | 31.3 °F | 55.0 °F | 1.86 in. |
| May | 44.3 °F | 67.9 °F | 3.29 in. |
| June | 55.1 °F | 77.4 °F | 3.66 in. |
| July | 59.6 °F | 82.9 °F | 3.45 in. |
| August | 56.9 °F | 81.4 °F | 2.71 in. |
| September | 47.4 °F | 73.0 °F | 2.08 in. |
| October | 34.0 °F | 57.7 °F | 1.74 in. |
| November | 20.3 °F | 40.5 °F | 0.64 in. |
| December | 8.8 °F | 26.8 °F | 0.6 in. |
| Annual | 32.1 °F | 54.2 °F | 22.11 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| 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 |