Atchison, Kansas has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.3 °C (low) to 18.2 °C (high). Annual precipitation averages 936.2 Millimeters. Atchison 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.9 °C | 2.8 °C | 24.89 mm |
| February | -5.7 °C | 5.8 °C | 32.51 mm |
| March | -0.1 °C | 12.6 °C | 51.56 mm |
| April | 5.7 °C | 18.7 °C | 90.68 mm |
| May | 12.2 °C | 23.9 °C | 131.83 mm |
| June | 17.7 °C | 29.1 °C | 125.48 mm |
| July | 19.8 °C | 31.2 °C | 126.49 mm |
| August | 18.5 °C | 30.5 °C | 99.31 mm |
| September | 13.7 °C | 26.5 °C | 90.68 mm |
| October | 6.7 °C | 19.8 °C | 79.5 mm |
| November | 0.2 °C | 12.2 °C | 47.24 mm |
| December | -5.4 °C | 5.2 °C | 36.07 mm |
| Annual | 6.3 °C | 18.2 °C | 936.24 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 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |