Shell Knob, Missouri has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.5 °C (low) to 20.5 °C (high). Annual precipitation averages 1152.2 Millimeters. Shell Knob is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.4 °C | 7.7 °C | 67.06 mm |
| February | -2.6 °C | 10.1 °C | 58.17 mm |
| March | 1.8 °C | 15.2 °C | 101.35 mm |
| April | 6.8 °C | 20.6 °C | 124.21 mm |
| May | 12.3 °C | 25.2 °C | 134.87 mm |
| June | 17.3 °C | 29.7 °C | 98.3 mm |
| July | 19.3 °C | 32.3 °C | 104.39 mm |
| August | 18.6 °C | 31.8 °C | 78.99 mm |
| September | 14.2 °C | 27.7 °C | 110.49 mm |
| October | 7.5 °C | 21.7 °C | 97.79 mm |
| November | 2 °C | 15 °C | 97.79 mm |
| December | -2.4 °C | 9.3 °C | 78.74 mm |
| Annual | 7.5 °C | 20.5 °C | 1152.15 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |