Birmingham, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.1 °C (low) to 16.4 °C (high). Annual precipitation averages 969.5 Millimeters. Birmingham is located in USDA Plant Hardiness Zone 5b. 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 | -9.4 °C | 0.1 °C | 36.58 mm |
| February | -7.4 °C | 2.7 °C | 44.7 mm |
| March | -1.5 °C | 9.9 °C | 58.42 mm |
| April | 4.5 °C | 17.2 °C | 95 mm |
| May | 11 °C | 22.8 °C | 136.4 mm |
| June | 16.5 °C | 28 °C | 126.24 mm |
| July | 18.6 °C | 30.1 °C | 105.41 mm |
| August | 17.2 °C | 29.2 °C | 97.79 mm |
| September | 12.3 °C | 25.5 °C | 92.96 mm |
| October | 5.9 °C | 18.3 °C | 74.93 mm |
| November | -0.6 °C | 9.9 °C | 57.66 mm |
| December | -6.1 °C | 2.9 °C | 43.43 mm |
| Annual | 5.1 °C | 16.4 °C | 969.52 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 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |