Malcom, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.7 °C (low) to 14.8 °C (high). Annual precipitation averages 949.2 Millimeters. Malcom 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.3 °C | -2.2 °C | 27.43 mm |
| February | -9.4 °C | 0.5 °C | 34.54 mm |
| March | -3.2 °C | 7.8 °C | 53.85 mm |
| April | 2.9 °C | 15.4 °C | 94.49 mm |
| May | 10 °C | 21.7 °C | 122.68 mm |
| June | 16 °C | 27.2 °C | 139.19 mm |
| July | 17.8 °C | 29.1 °C | 110.24 mm |
| August | 16.2 °C | 28 °C | 111 mm |
| September | 11.2 °C | 24.3 °C | 90.93 mm |
| October | 4.6 °C | 16.9 °C | 72.9 mm |
| November | -2.1 °C | 8.2 °C | 53.34 mm |
| December | -7.9 °C | 1 °C | 38.61 mm |
| Annual | 3.7 °C | 14.8 °C | 949.2 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |