Blunt, South Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 0.8 °C (low) to 14.6 °C (high). Annual precipitation averages 518.2 Millimeters. Blunt 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 Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.2 °C | -2.2 °C | 11.43 mm |
| February | -11.9 °C | 0.4 °C | 15.75 mm |
| March | -6.2 °C | 7.3 °C | 22.61 mm |
| April | -0.6 °C | 14.6 °C | 51.82 mm |
| May | 6.3 °C | 20.7 °C | 78.74 mm |
| June | 12.8 °C | 26 °C | 91.69 mm |
| July | 16.1 °C | 30.5 °C | 68.33 mm |
| August | 14.3 °C | 29.5 °C | 59.69 mm |
| September | 9.3 °C | 25 °C | 46.99 mm |
| October | 1.2 °C | 15.9 °C | 42.42 mm |
| November | -6 °C | 7.3 °C | 14.99 mm |
| December | -11.8 °C | -0.1 °C | 13.72 mm |
| Annual | 0.8 °C | 14.6 °C | 518.18 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 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |