Romeo, Michigan has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38.9 °F (low) to 57.7 °F (high). Annual precipitation averages 34.5 Inches. Romeo is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 16.1 °F | 30.8 °F | 2.58 in. |
| February | 16.8 °F | 33.8 °F | 2.02 in. |
| March | 24.9 °F | 43.5 °F | 2.32 in. |
| April | 35.7 °F | 56.4 °F | 3.32 in. |
| May | 47.2 °F | 68.7 °F | 3.57 in. |
| June | 57.1 °F | 78.4 °F | 3.15 in. |
| July | 61.2 °F | 82.6 °F | 3.76 in. |
| August | 59.9 °F | 80.7 °F | 3.19 in. |
| September | 52.5 °F | 74.2 °F | 2.82 in. |
| October | 41.4 °F | 60.4 °F | 2.81 in. |
| November | 31.5 °F | 47.6 °F | 2.6 in. |
| December | 22.9 °F | 35.7 °F | 2.37 in. |
| Annual | 38.9 °F | 57.7 °F | 34.51 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |