Masonville, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.4 °C (low) to 13.7 °C (high). Annual precipitation averages 983.2 Millimeters. Masonville is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.1 °C | -3.3 °C | 29.97 mm |
| February | -10.9 °C | -0.9 °C | 32.51 mm |
| March | -4.3 °C | 6.4 °C | 52.83 mm |
| April | 1.9 °C | 14.3 °C | 98.3 mm |
| May | 8.6 °C | 20.8 °C | 119.38 mm |
| June | 14.6 °C | 26.2 °C | 150.62 mm |
| July | 16.3 °C | 27.8 °C | 120.9 mm |
| August | 14.8 °C | 26.8 °C | 109.47 mm |
| September | 10 °C | 23.4 °C | 96.52 mm |
| October | 3.3 °C | 16.1 °C | 75.95 mm |
| November | -3.3 °C | 7.2 °C | 55.63 mm |
| December | -9.3 °C | -0.1 °C | 41.15 mm |
| Annual | 2.4 °C | 13.7 °C | 983.23 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 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 |