Bernard, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.9 °C (low) to 13.9 °C (high). Annual precipitation averages 987.5 Millimeters. Bernard 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 | -12.2 °C | -2.9 °C | 32.26 mm |
| February | -10.2 °C | -0.4 °C | 38.35 mm |
| March | -3.8 °C | 6.8 °C | 55.37 mm |
| April | 2.3 °C | 14.6 °C | 96.77 mm |
| May | 8.9 °C | 20.9 °C | 113.79 mm |
| June | 14.6 °C | 26.2 °C | 148.34 mm |
| July | 16.5 °C | 27.9 °C | 119.38 mm |
| August | 15.2 °C | 26.9 °C | 109.98 mm |
| September | 10.3 °C | 23.3 °C | 95 mm |
| October | 3.8 °C | 16.1 °C | 76.45 mm |
| November | -2.7 °C | 7.5 °C | 57.91 mm |
| December | -8.4 °C | 0.3 °C | 43.94 mm |
| Annual | 2.9 °C | 13.9 °C | 987.54 mm |
| 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 : -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 |