Alpine, Wyoming has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 28 °F (low) to 54.5 °F (high). Annual precipitation averages 23.7 Inches. Alpine is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 9.5 °F | 28.6 °F | 3.98 in. |
| February | 10.9 °F | 32.2 °F | 2.42 in. |
| March | 18.8 °F | 41.6 °F | 1.57 in. |
| April | 27.8 °F | 51.4 °F | 2.18 in. |
| May | 35.7 °F | 62.7 °F | 2.28 in. |
| June | 41.4 °F | 72.5 °F | 1.68 in. |
| July | 46.7 °F | 83.5 °F | 0.91 in. |
| August | 45.6 °F | 82.2 °F | 1.61 in. |
| September | 37.4 °F | 72.4 °F | 1.62 in. |
| October | 29.9 °F | 57.3 °F | 1.49 in. |
| November | 20.5 °F | 40.7 °F | 2.41 in. |
| December | 11.4 °F | 28.4 °F | 1.57 in. |
| Annual | 28 °F | 54.5 °F | 23.72 in. |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |