Knierim, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 37.1 °F (low) to 57.4 °F (high). Annual precipitation averages 34.2 Inches. Knierim 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 | 8.9 °F | 26.4 °F | 0.83 in. |
| February | 12.9 °F | 30.9 °F | 1.06 in. |
| March | 24.9 °F | 44.6 °F | 1.98 in. |
| April | 35.9 °F | 59.1 °F | 3.67 in. |
| May | 48.5 °F | 70.1 °F | 4.92 in. |
| June | 59.5 °F | 80.1 °F | 5.22 in. |
| July | 62.9 °F | 83.1 °F | 3.86 in. |
| August | 60.2 °F | 80.8 °F | 4.29 in. |
| September | 51.1 °F | 75.0 °F | 3.04 in. |
| October | 38.7 °F | 62.0 °F | 2.49 in. |
| November | 26.0 °F | 45.4 °F | 1.54 in. |
| December | 15.1 °F | 31.7 °F | 1.3 in. |
| Annual | 37.1 °F | 57.4 °F | 34.2 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |