Carlinville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.8 °F (low) to 63.7 °F (high). Annual precipitation averages 40.5 Inches. Carlinville is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.0 °F | 36.0 °F | 2.32 in. |
| February | 23.6 °F | 41.1 °F | 2.05 in. |
| March | 32.5 °F | 52.3 °F | 2.94 in. |
| April | 42.9 °F | 65.0 °F | 4.66 in. |
| May | 54.1 °F | 74.8 °F | 4.72 in. |
| June | 63.0 °F | 83.2 °F | 4.28 in. |
| July | 66.2 °F | 86.2 °F | 3.78 in. |
| August | 64.0 °F | 85.1 °F | 3.38 in. |
| September | 55.7 °F | 79.5 °F | 3.34 in. |
| October | 44.4 °F | 67.4 °F | 3.32 in. |
| November | 34.1 °F | 52.8 °F | 3.41 in. |
| December | 25.1 °F | 40.9 °F | 2.3 in. |
| Annual | 43.8 °F | 63.7 °F | 40.5 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |