Marion, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.6 °C (low) to 11.1 °C (high). Annual precipitation averages 555.7 Millimeters. Marion is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -17.5 °C | -7.4 °C | 13.46 mm |
| February | -15.4 °C | -4.7 °C | 14.48 mm |
| March | -8.5 °C | 2.2 °C | 25.65 mm |
| April | -1.1 °C | 11.5 °C | 34.54 mm |
| May | 6.3 °C | 19.1 °C | 77.72 mm |
| June | 12.6 °C | 24.5 °C | 96.01 mm |
| July | 14.9 °C | 27.2 °C | 90.17 mm |
| August | 13.1 °C | 26.6 °C | 58.67 mm |
| September | 7.9 °C | 21.9 °C | 60.2 mm |
| October | 0.7 °C | 13.1 °C | 49.78 mm |
| November | -6.9 °C | 3.5 °C | 16.76 mm |
| December | -13.6 °C | -4.3 °C | 18.29 mm |
| Annual | -0.6 °C | 11.1 °C | 555.73 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |