Yankton, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 37 °F (low) to 58.9 °F (high). Annual precipitation averages 27.3 Inches. Yankton 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 | 9.7 °F | 29.0 °F | 0.55 in. |
| February | 13.3 °F | 34.0 °F | 0.74 in. |
| March | 24.1 °F | 46.0 °F | 1.43 in. |
| April | 35.5 °F | 58.8 °F | 2.91 in. |
| May | 47.8 °F | 70.4 °F | 4.12 in. |
| June | 59.0 °F | 81.0 °F | 4.17 in. |
| July | 63.5 °F | 85.6 °F | 2.9 in. |
| August | 61.0 °F | 83.3 °F | 3.2 in. |
| September | 51.7 °F | 76.2 °F | 2.84 in. |
| October | 38.3 °F | 62.5 °F | 2.57 in. |
| November | 25.2 °F | 46.5 °F | 1.08 in. |
| December | 14.5 °F | 33.2 °F | 0.81 in. |
| Annual | 37 °F | 58.9 °F | 27.32 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |