Le Grand, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.3 °F (low) to 58.4 °F (high). Annual precipitation averages 36.6 Inches. Le Grand is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 10.9 °F | 27.7 °F | 1.01 in. |
| February | 14.7 °F | 32.5 °F | 1.15 in. |
| March | 25.9 °F | 45.6 °F | 2.03 in. |
| April | 37.2 °F | 59.8 °F | 3.83 in. |
| May | 49.7 °F | 70.9 °F | 4.93 in. |
| June | 60.4 °F | 80.6 °F | 5.5 in. |
| July | 63.6 °F | 83.8 °F | 4.31 in. |
| August | 60.8 °F | 81.9 °F | 4.27 in. |
| September | 52.1 °F | 75.8 °F | 3.47 in. |
| October | 39.9 °F | 62.4 °F | 2.67 in. |
| November | 27.7 °F | 46.6 °F | 2.02 in. |
| December | 17.1 °F | 33.5 °F | 1.44 in. |
| Annual | 38.3 °F | 58.4 °F | 36.63 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |