Worth, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.1 °F (low) to 60.2 °F (high). Annual precipitation averages 39.8 Inches. Worth 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 | 17.4 °F | 31.9 °F | 2.18 in. |
| February | 20.2 °F | 35.7 °F | 2.06 in. |
| March | 29.5 °F | 46.7 °F | 2.39 in. |
| April | 39.8 °F | 60.0 °F | 3.98 in. |
| May | 50.8 °F | 71.1 °F | 4.78 in. |
| June | 60.9 °F | 81.1 °F | 4.34 in. |
| July | 65.8 °F | 85.6 °F | 4.28 in. |
| August | 64.2 °F | 83.5 °F | 4.21 in. |
| September | 56.6 °F | 77.1 °F | 3.23 in. |
| October | 44.2 °F | 63.7 °F | 3.47 in. |
| November | 33.2 °F | 49.1 °F | 2.55 in. |
| December | 23.1 °F | 37.2 °F | 2.34 in. |
| Annual | 42.1 °F | 60.2 °F | 39.81 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 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |