Elmwood, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.8 °F (low) to 61.3 °F (high). Annual precipitation averages 38 Inches. Elmwood 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 | 15.2 °F | 32.1 °F | 1.94 in. |
| February | 18.7 °F | 36.8 °F | 1.99 in. |
| March | 28.8 °F | 49.5 °F | 2.46 in. |
| April | 39.5 °F | 62.6 °F | 3.59 in. |
| May | 51.5 °F | 73.3 °F | 4.89 in. |
| June | 61.1 °F | 82.2 °F | 4.64 in. |
| July | 64.4 °F | 85.2 °F | 4.13 in. |
| August | 62.1 °F | 83.7 °F | 3.5 in. |
| September | 53.9 °F | 77.9 °F | 3.8 in. |
| October | 42.0 °F | 65.2 °F | 2.82 in. |
| November | 30.8 °F | 50.1 °F | 2.33 in. |
| December | 21.2 °F | 37.5 °F | 1.94 in. |
| Annual | 40.8 °F | 61.3 °F | 38.03 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |