Romeo, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -3.6 °C (low) to 14.9 °C (high). Annual precipitation averages 198.9 Millimeters. Romeo is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -16.5 °C | 1.4 °C | 5.33 mm |
| February | -12.6 °C | 4.6 °C | 5.33 mm |
| March | -7.5 °C | 10.4 °C | 11.18 mm |
| April | -3.8 °C | 14.7 °C | 13.46 mm |
| May | 1.2 °C | 19.6 °C | 16.76 mm |
| June | 5.2 °C | 25.2 °C | 9.91 mm |
| July | 8.6 °C | 26.8 °C | 31.5 mm |
| August | 7.5 °C | 25.6 °C | 38.35 mm |
| September | 3.4 °C | 22.7 °C | 28.19 mm |
| October | -3.1 °C | 16.8 °C | 18.29 mm |
| November | -9.6 °C | 9.2 °C | 11.94 mm |
| December | -15.7 °C | 2.1 °C | 8.64 mm |
| Annual | -3.6 °C | 14.9 °C | 198.88 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 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 | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |