Geddes, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.5 °C (low) to 15.5 °C (high). Annual precipitation averages 633.2 Millimeters. Geddes 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 | -12.1 °C | -0.4 °C | 13.21 mm |
| February | -10 °C | 2.3 °C | 17.78 mm |
| March | -4.6 °C | 8.7 °C | 29.46 mm |
| April | 1.5 °C | 15.2 °C | 75.95 mm |
| May | 8.1 °C | 21.4 °C | 93.47 mm |
| June | 14.2 °C | 27.1 °C | 97.28 mm |
| July | 17.1 °C | 30.8 °C | 73.41 mm |
| August | 15.8 °C | 29.6 °C | 76.2 mm |
| September | 10.6 °C | 25.3 °C | 66.04 mm |
| October | 3.1 °C | 16.9 °C | 52.58 mm |
| November | -4.2 °C | 8.3 °C | 21.34 mm |
| December | -9.8 °C | 1.2 °C | 16.51 mm |
| Annual | 2.5 °C | 15.5 °C | 633.23 mm |
| 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 : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |