Dearborn, Michigan has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.4 °C (low) to 15.1 °C (high). Annual precipitation averages 894.6 Millimeters. Dearborn is located in USDA Plant Hardiness Zone 6b. 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 | -7.1 °C | 0.3 °C | 60.45 mm |
| February | -6.4 °C | 1.9 °C | 55.37 mm |
| March | -2.3 °C | 7.3 °C | 66.04 mm |
| April | 3.4 °C | 14.4 °C | 81.53 mm |
| May | 9.7 °C | 21 °C | 94.49 mm |
| June | 15.4 °C | 26.3 °C | 82.55 mm |
| July | 17.8 °C | 28.7 °C | 88.39 mm |
| August | 17.1 °C | 27.7 °C | 82.8 mm |
| September | 13.1 °C | 24.1 °C | 80.52 mm |
| October | 6.6 °C | 16.8 °C | 74.68 mm |
| November | 1.1 °C | 9.5 °C | 67.31 mm |
| December | -3.6 °C | 3.2 °C | 60.45 mm |
| Annual | 5.4 °C | 15.1 °C | 894.58 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 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |