Dunlap, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.8 °F (low) to 60.7 °F (high). Annual precipitation averages 38.7 Inches. Dunlap is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.3 °F | 31.4 °F | 2.04 in. |
| February | 17.9 °F | 36.0 °F | 1.98 in. |
| March | 27.9 °F | 48.6 °F | 2.53 in. |
| April | 38.5 °F | 62.1 °F | 3.8 in. |
| May | 50.4 °F | 72.9 °F | 4.9 in. |
| June | 60.1 °F | 81.6 °F | 4.47 in. |
| July | 63.3 °F | 84.5 °F | 3.91 in. |
| August | 61.1 °F | 83.0 °F | 3.57 in. |
| September | 52.8 °F | 77.3 °F | 3.58 in. |
| October | 41.2 °F | 64.7 °F | 3.09 in. |
| November | 29.9 °F | 49.5 °F | 2.71 in. |
| December | 20.3 °F | 36.8 °F | 2.08 in. |
| Annual | 39.8 °F | 60.7 °F | 38.66 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |