Parkman, Wyoming has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31 °F (low) to 58.1 °F (high). Annual precipitation averages 18.1 Inches. Parkman is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Sep.1 - Sep. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.5 °F | 36.9 °F | 0.77 in. |
| February | 14.1 °F | 38.3 °F | 0.8 in. |
| March | 22.3 °F | 47.8 °F | 1.26 in. |
| April | 29.5 °F | 54.8 °F | 2.22 in. |
| May | 38.5 °F | 63.4 °F | 3.65 in. |
| June | 46.6 °F | 73.9 °F | 2.31 in. |
| July | 52.3 °F | 83.9 °F | 1.22 in. |
| August | 50.2 °F | 83.0 °F | 0.88 in. |
| September | 41.8 °F | 72.5 °F | 1.57 in. |
| October | 30.9 °F | 58.0 °F | 1.77 in. |
| November | 19.9 °F | 46.4 °F | 0.93 in. |
| December | 13.1 °F | 38.2 °F | 0.73 in. |
| Annual | 31 °F | 58.1 °F | 18.11 in. |
| Average First Frost Date | Sep.1 - Sep. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |