Rolla, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2.6 °C (low) to 8.6 °C (high). Annual precipitation averages 501.6 Millimeters. Rolla is located in USDA Plant Hardiness Zone 4a. 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 | -19.6 °C | -9.7 °C | 13.97 mm |
| February | -17.9 °C | -7.3 °C | 13.46 mm |
| March | -10.8 °C | -0.9 °C | 18.54 mm |
| April | -2.8 °C | 8.9 °C | 25.4 mm |
| May | 4.3 °C | 16.9 °C | 67.31 mm |
| June | 10.4 °C | 21.8 °C | 97.79 mm |
| July | 12.8 °C | 24.6 °C | 79.5 mm |
| August | 11.4 °C | 24.7 °C | 66.8 mm |
| September | 6.3 °C | 19.4 °C | 44.7 mm |
| October | -0.8 °C | 10.6 °C | 35.81 mm |
| November | -8.9 °C | 0.5 °C | 20.57 mm |
| December | -16.1 °C | -6.9 °C | 17.78 mm |
| Annual | -2.6 °C | 8.6 °C | 501.63 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |