Matherville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.5 °F (low) to 60 °F (high). Annual precipitation averages 38 Inches. Matherville is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.2 °F | 30.4 °F | 1.57 in. |
| February | 17.6 °F | 34.9 °F | 1.81 in. |
| March | 28.3 °F | 48.2 °F | 2.43 in. |
| April | 39.2 °F | 61.4 °F | 3.78 in. |
| May | 51.2 °F | 72.2 °F | 4.92 in. |
| June | 61.0 °F | 81.1 °F | 4.77 in. |
| July | 64.6 °F | 84.2 °F | 4.03 in. |
| August | 62.4 °F | 82.4 °F | 3.84 in. |
| September | 54.2 °F | 76.5 °F | 3.67 in. |
| October | 42.4 °F | 63.6 °F | 2.86 in. |
| November | 30.5 °F | 48.7 °F | 2.32 in. |
| December | 20.2 °F | 35.9 °F | 1.97 in. |
| Annual | 40.5 °F | 60 °F | 37.97 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 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 |