Elmwood, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.9 °C (low) to 16.3 °C (high). Annual precipitation averages 966 Millimeters. 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 | -9.3 °C | 0.1 °C | 49.28 mm |
| February | -7.4 °C | 2.7 °C | 50.55 mm |
| March | -1.8 °C | 9.7 °C | 62.48 mm |
| April | 4.2 °C | 17 °C | 91.19 mm |
| May | 10.8 °C | 22.9 °C | 124.21 mm |
| June | 16.2 °C | 27.9 °C | 117.86 mm |
| July | 18 °C | 29.6 °C | 104.9 mm |
| August | 16.7 °C | 28.7 °C | 88.9 mm |
| September | 12.2 °C | 25.5 °C | 96.52 mm |
| October | 5.6 °C | 18.4 °C | 71.63 mm |
| November | -0.7 °C | 10.1 °C | 59.18 mm |
| December | -6 °C | 3.1 °C | 49.28 mm |
| Annual | 4.9 °C | 16.3 °C | 965.98 mm |
| 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 : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |