Rapid Valley, South Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 2.1 °C (low) to 15.2 °C (high). Annual precipitation averages 479.6 Millimeters. Rapid Valley is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.8 °C | 2.4 °C | 8.38 mm |
| February | -8.8 °C | 3.4 °C | 12.7 mm |
| March | -4.3 °C | 8.8 °C | 24.89 mm |
| April | 0.4 °C | 13.2 °C | 53.34 mm |
| May | 6.4 °C | 18.4 °C | 98.55 mm |
| June | 11.9 °C | 24.8 °C | 80.52 mm |
| July | 15.7 °C | 29.7 °C | 58.17 mm |
| August | 14.6 °C | 29.1 °C | 47.75 mm |
| September | 9.4 °C | 24.1 °C | 34.8 mm |
| October | 2.4 °C | 15.9 °C | 37.85 mm |
| November | -3.8 °C | 8.8 °C | 12.7 mm |
| December | -8.6 °C | 3.2 °C | 9.91 mm |
| Annual | 2.1 °C | 15.2 °C | 479.56 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |