Barry, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.2 °F (low) to 63 °F (high). Annual precipitation averages 39.3 Inches. Barry is located in USDA Plant Hardiness Zone 6a. 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 | 18.5 °F | 35.2 °F | 1.92 in. |
| February | 22.1 °F | 40.3 °F | 1.93 in. |
| March | 31.6 °F | 51.7 °F | 2.68 in. |
| April | 42.3 °F | 64.0 °F | 4.34 in. |
| May | 53.5 °F | 73.8 °F | 4.81 in. |
| June | 62.8 °F | 82.5 °F | 4.66 in. |
| July | 66.2 °F | 86.2 °F | 3.99 in. |
| August | 64.1 °F | 85.1 °F | 3.36 in. |
| September | 55.4 °F | 78.7 °F | 3.45 in. |
| October | 44.1 °F | 66.3 °F | 3.12 in. |
| November | 33.4 °F | 52.4 °F | 2.89 in. |
| December | 23.8 °F | 39.9 °F | 2.1 in. |
| Annual | 43.2 °F | 63 °F | 39.25 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 6a : -10°F to -5°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 |