Robertson, Wyoming has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -2 °C (low) to 12.7 °C (high). Annual precipitation averages 302.8 Millimeters. Robertson is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Jun. 11 - Jun. 20 through the first frost around Aug. 21 - Aug. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.4 °C | 0.8 °C | 16.26 mm |
| February | -10.9 °C | 1.4 °C | 17.02 mm |
| March | -6.8 °C | 6.3 °C | 21.34 mm |
| April | -3.4 °C | 11 °C | 30.23 mm |
| May | 1.2 °C | 16.3 °C | 39.12 mm |
| June | 5.2 °C | 22.2 °C | 25.91 mm |
| July | 9.2 °C | 26.9 °C | 27.94 mm |
| August | 8.7 °C | 26.1 °C | 25.4 mm |
| September | 4.1 °C | 21.1 °C | 30.73 mm |
| October | -1.3 °C | 13.8 °C | 28.96 mm |
| November | -7.1 °C | 5.8 °C | 21.84 mm |
| December | -11.3 °C | 0.5 °C | 18.03 mm |
| Annual | -2 °C | 12.7 °C | 302.78 mm |
| Average First Frost Date | Aug. 21 - Aug. 31 |
| Average Last Frost Date | Jun. 11 - Jun. 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |