Catlin, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.7 °C (low) to 16.8 °C (high). Annual precipitation averages 1046.2 Millimeters. Catlin is located in USDA Plant Hardiness Zone 6a. 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 | -7.6 °C | 1.1 °C | 62.48 mm |
| February | -5.9 °C | 3.7 °C | 54.61 mm |
| March | -0.7 °C | 10.1 °C | 74.93 mm |
| April | 5.2 °C | 17.6 °C | 106.43 mm |
| May | 11.4 °C | 23.4 °C | 117.09 mm |
| June | 16.5 °C | 28 °C | 124.21 mm |
| July | 18.1 °C | 29.4 °C | 108.2 mm |
| August | 16.8 °C | 28.6 °C | 82.3 mm |
| September | 12.6 °C | 25.9 °C | 77.98 mm |
| October | 6.3 °C | 19.1 °C | 87.63 mm |
| November | 0.4 °C | 10.7 °C | 85.85 mm |
| December | -4.4 °C | 3.8 °C | 64.52 mm |
| Annual | 5.7 °C | 16.8 °C | 1046.23 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 6a : -23.3°C to -20.6°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 |