Halltown, Missouri has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.4 °C (low) to 19.6 °C (high). Annual precipitation averages 1156 Millimeters. Halltown is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.1 °C | 6.2 °C | 61.72 mm |
| February | -3.2 °C | 8.9 °C | 55.63 mm |
| March | 1.5 °C | 14.2 °C | 94.49 mm |
| April | 6.7 °C | 19.7 °C | 118.11 mm |
| May | 12.4 °C | 24.1 °C | 150.11 mm |
| June | 17.4 °C | 29 °C | 118.36 mm |
| July | 19.6 °C | 31.6 °C | 99.82 mm |
| August | 18.7 °C | 31.4 °C | 87.88 mm |
| September | 14.1 °C | 27.3 °C | 116.08 mm |
| October | 7.5 °C | 20.9 °C | 90.68 mm |
| November | 1.7 °C | 13.8 °C | 92.46 mm |
| December | -3.1 °C | 8.1 °C | 70.61 mm |
| Annual | 7.4 °C | 19.6 °C | 1155.95 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°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 |