Charlotte, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.9 °F (low) to 59 °F (high). Annual precipitation averages 37.9 Inches. Charlotte is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.3 °F | 29.1 °F | 1.43 in. |
| February | 15.9 °F | 33.6 °F | 1.67 in. |
| March | 26.8 °F | 46.4 °F | 2.38 in. |
| April | 37.8 °F | 59.9 °F | 3.74 in. |
| May | 49.6 °F | 71.5 °F | 4.57 in. |
| June | 59.7 °F | 80.7 °F | 5.05 in. |
| July | 63.1 °F | 83.7 °F | 4.3 in. |
| August | 60.9 °F | 81.8 °F | 4.16 in. |
| September | 52.4 °F | 75.9 °F | 3.65 in. |
| October | 40.8 °F | 63.0 °F | 2.91 in. |
| November | 29.1 °F | 47.7 °F | 2.22 in. |
| December | 18.7 °F | 34.7 °F | 1.85 in. |
| Annual | 38.9 °F | 59 °F | 37.93 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |