Simpson, Kansas has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.6 °F (low) to 66.7 °F (high). Annual precipitation averages 28.7 Inches. Simpson 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 | 18.1 °F | 39.9 °F | 0.69 in. |
| February | 21.4 °F | 44.6 °F | 0.93 in. |
| March | 30.6 °F | 56.1 °F | 1.56 in. |
| April | 40.6 °F | 66.4 °F | 2.46 in. |
| May | 52.1 °F | 76.0 °F | 4.46 in. |
| June | 63.0 °F | 87.3 °F | 4.08 in. |
| July | 68.0 °F | 92.4 °F | 4.36 in. |
| August | 65.6 °F | 89.6 °F | 3.49 in. |
| September | 56.6 °F | 82.2 °F | 2.59 in. |
| October | 43.2 °F | 69.4 °F | 1.87 in. |
| November | 30.5 °F | 54.4 °F | 1.13 in. |
| December | 21.3 °F | 42.2 °F | 1.03 in. |
| Annual | 42.6 °F | 66.7 °F | 28.65 in. |
| 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 : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |