Morton Grove, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43 °F (low) to 58.8 °F (high). Annual precipitation averages 39.2 Inches. Morton Grove 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.2 °F | 31.7 °F | 2.21 in. |
| February | 21.1 °F | 35.6 °F | 2.13 in. |
| March | 29.8 °F | 45.6 °F | 2.25 in. |
| April | 40.0 °F | 57.1 °F | 3.86 in. |
| May | 51.1 °F | 68.7 °F | 4.69 in. |
| June | 61.1 °F | 78.9 °F | 4.43 in. |
| July | 66.8 °F | 83.2 °F | 3.72 in. |
| August | 65.6 °F | 81.4 °F | 4.09 in. |
| September | 58.0 °F | 74.9 °F | 3.48 in. |
| October | 45.8 °F | 62.6 °F | 3.45 in. |
| November | 34.0 °F | 48.3 °F | 2.6 in. |
| December | 24.3 °F | 37.0 °F | 2.3 in. |
| Annual | 43 °F | 58.8 °F | 39.21 in. |
| 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |