Carson, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.3 °F (low) to 60.8 °F (high). Annual precipitation averages 34.9 Inches. Carson is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.2 °F | 31.2 °F | 0.82 in. |
| February | 16.3 °F | 36.2 °F | 1.05 in. |
| March | 27.3 °F | 49.5 °F | 1.88 in. |
| April | 38.1 °F | 62.1 °F | 3.59 in. |
| May | 50.5 °F | 72.4 °F | 5.4 in. |
| June | 61.1 °F | 82.1 °F | 5.27 in. |
| July | 64.9 °F | 85.6 °F | 3.8 in. |
| August | 62.2 °F | 83.7 °F | 3.9 in. |
| September | 52.9 °F | 77.5 °F | 3.38 in. |
| October | 40.4 °F | 64.6 °F | 2.87 in. |
| November | 27.7 °F | 48.7 °F | 1.61 in. |
| December | 17.8 °F | 36.0 °F | 1.3 in. |
| Annual | 39.3 °F | 60.8 °F | 34.87 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°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 |