Bonnie, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 45.8 °F (low) to 65.8 °F (high). Annual precipitation averages 45.8 Inches. Bonnie 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.3 °F | 39.7 °F | 3.16 in. |
| February | 26.3 °F | 44.6 °F | 2.75 in. |
| March | 34.9 °F | 54.8 °F | 3.93 in. |
| April | 45.2 °F | 66.6 °F | 5.0 in. |
| May | 55.8 °F | 75.7 °F | 5.28 in. |
| June | 64.3 °F | 84.7 °F | 4.74 in. |
| July | 67.7 °F | 87.7 °F | 4.18 in. |
| August | 65.4 °F | 86.9 °F | 3.1 in. |
| September | 57.4 °F | 80.7 °F | 3.14 in. |
| October | 45.7 °F | 69.2 °F | 3.3 in. |
| November | 35.6 °F | 55.1 °F | 4.08 in. |
| December | 27.6 °F | 43.9 °F | 3.1 in. |
| Annual | 45.8 °F | 65.8 °F | 45.76 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| 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 6b : -5°F to 0°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |