Norris City, Illinois has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.8 °C (low) to 19.2 °C (high). Annual precipitation averages 1184.4 Millimeters. Norris City is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.3 °C | 4.8 °C | 89.66 mm |
| February | -2.9 °C | 7.6 °C | 75.95 mm |
| March | 1.7 °C | 13.1 °C | 106.93 mm |
| April | 7.3 °C | 19.6 °C | 127.25 mm |
| May | 13.2 °C | 24.7 °C | 131.06 mm |
| June | 18.1 °C | 29.4 °C | 113.54 mm |
| July | 19.7 °C | 31 °C | 101.85 mm |
| August | 18.4 °C | 30.6 °C | 77.47 mm |
| September | 14.2 °C | 27.6 °C | 80.52 mm |
| October | 7.7 °C | 21.1 °C | 86.36 mm |
| November | 2.1 °C | 13.3 °C | 101.85 mm |
| December | -2.2 °C | 7.2 °C | 91.95 mm |
| Annual | 7.8 °C | 19.2 °C | 1184.39 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |