Rapids City, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5 °C (low) to 15.6 °C (high). Annual precipitation averages 970 Millimeters. Rapids City 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.8 °C | -0.8 °C | 38.86 mm |
| February | -7.8 °C | 1.6 °C | 44.2 mm |
| March | -1.8 °C | 8.7 °C | 64.01 mm |
| April | 4.3 °C | 16.1 °C | 93.98 mm |
| May | 10.9 °C | 22.3 °C | 120.9 mm |
| June | 16.5 °C | 27.6 °C | 124.97 mm |
| July | 18.5 °C | 29.3 °C | 112.78 mm |
| August | 17.3 °C | 28.3 °C | 102.11 mm |
| September | 12.7 °C | 24.9 °C | 87.88 mm |
| October | 6.2 °C | 17.7 °C | 71.37 mm |
| November | -0.5 °C | 9.3 °C | 57.15 mm |
| December | -6.3 °C | 2.2 °C | 51.82 mm |
| Annual | 5 °C | 15.6 °C | 970.03 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 |