Van Tassell, Wyoming has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.4 °C (low) to 15.4 °C (high). Annual precipitation averages 404.4 Millimeters. Van Tassell 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.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.1 °C | 3.2 °C | 7.87 mm |
| February | -9.9 °C | 4 °C | 12.45 mm |
| March | -5.7 °C | 9.7 °C | 23.88 mm |
| April | -1.8 °C | 13.1 °C | 49.02 mm |
| May | 3.6 °C | 18.4 °C | 76.96 mm |
| June | 9 °C | 25 °C | 62.23 mm |
| July | 12.6 °C | 29.9 °C | 48.01 mm |
| August | 11.3 °C | 29.3 °C | 33.78 mm |
| September | 5.8 °C | 24.1 °C | 33.27 mm |
| October | -1.1 °C | 15.5 °C | 34.04 mm |
| November | -6.9 °C | 8.8 °C | 13.21 mm |
| December | -10.9 °C | 3.3 °C | 9.65 mm |
| Annual | -0.4 °C | 15.4 °C | 404.37 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |