Cairo, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.9 °F (low) to 63.8 °F (high). Annual precipitation averages 42.4 Inches. Cairo is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.8 °F | 36.5 °F | 1.81 in. |
| February | 22.5 °F | 41.7 °F | 2.04 in. |
| March | 32.6 °F | 53.5 °F | 3.01 in. |
| April | 43.3 °F | 65.0 °F | 4.49 in. |
| May | 53.7 °F | 73.9 °F | 5.25 in. |
| June | 63.1 °F | 82.7 °F | 5.26 in. |
| July | 67.0 °F | 87.0 °F | 4.66 in. |
| August | 64.8 °F | 85.8 °F | 3.89 in. |
| September | 56.1 °F | 78.4 °F | 3.96 in. |
| October | 45.2 °F | 67.2 °F | 3.3 in. |
| November | 34.3 °F | 53.3 °F | 2.65 in. |
| December | 24.8 °F | 41.1 °F | 2.05 in. |
| Annual | 43.9 °F | 63.8 °F | 42.37 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| 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 |