Monroe, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.6 °C (low) to 17.6 °C (high). Annual precipitation averages 1073.2 Millimeters. Monroe is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.7 °C | 3.5 °C | 80.26 mm |
| February | -4.6 °C | 5.7 °C | 64.01 mm |
| March | -0.1 °C | 11.2 °C | 93.73 mm |
| April | 5.8 °C | 17.9 °C | 112.27 mm |
| May | 11.7 °C | 23.3 °C | 116.59 mm |
| June | 16.7 °C | 27.7 °C | 115.32 mm |
| July | 18.7 °C | 29.6 °C | 98.81 mm |
| August | 17.6 °C | 29.2 °C | 81.03 mm |
| September | 13.6 °C | 25.9 °C | 71.88 mm |
| October | 6.7 °C | 19.3 °C | 77.22 mm |
| November | 1.1 °C | 11.9 °C | 77.22 mm |
| December | -2.8 °C | 5.8 °C | 84.84 mm |
| Annual | 6.6 °C | 17.6 °C | 1073.18 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |