Arapahoe, Wyoming has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -0.9 °C (low) to 15.5 °C (high). Annual precipitation averages 249.9 Millimeters. Arapahoe is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -14.3 °C | 0.6 °C | 9.65 mm |
| February | -11.7 °C | 3.3 °C | 12.45 mm |
| March | -5.4 °C | 10.3 °C | 19.3 mm |
| April | -0.9 °C | 14.7 °C | 35.05 mm |
| May | 4.2 °C | 19.9 °C | 53.09 mm |
| June | 8.8 °C | 26.7 °C | 25.91 mm |
| July | 12.5 °C | 32.1 °C | 16.51 mm |
| August | 11.2 °C | 30.8 °C | 12.45 mm |
| September | 6.2 °C | 24.6 °C | 21.34 mm |
| October | -0.4 °C | 15.8 °C | 24.38 mm |
| November | -7.7 °C | 7.3 °C | 11.43 mm |
| December | -13.3 °C | 0.4 °C | 8.38 mm |
| Annual | -0.9 °C | 15.5 °C | 249.94 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |