Wapello, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.7 °F (low) to 61 °F (high). Annual precipitation averages 36.9 Inches. Wapello is located in USDA Plant Hardiness Zone 5b. 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 | 15.5 °F | 31.6 °F | 1.38 in. |
| February | 18.7 °F | 35.9 °F | 1.73 in. |
| March | 29.7 °F | 48.7 °F | 2.49 in. |
| April | 40.7 °F | 62.0 °F | 3.52 in. |
| May | 52.3 °F | 72.8 °F | 4.92 in. |
| June | 62.3 °F | 82.3 °F | 4.94 in. |
| July | 65.8 °F | 85.9 °F | 3.75 in. |
| August | 63.3 °F | 83.9 °F | 4.05 in. |
| September | 55.1 °F | 77.5 °F | 3.37 in. |
| October | 43.3 °F | 64.5 °F | 2.73 in. |
| November | 31.8 °F | 49.8 °F | 2.18 in. |
| December | 21.4 °F | 36.6 °F | 1.8 in. |
| Annual | 41.7 °F | 61 °F | 36.86 in. |
| 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 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |