Belcourt, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2.8 °C (low) to 8.5 °C (high). Annual precipitation averages 494 Millimeters. Belcourt is located in USDA Plant Hardiness Zone 3b. 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 | -19.7 °C | -9.4 °C | 12.95 mm |
| February | -18.1 °C | -7.1 °C | 12.19 mm |
| March | -11.2 °C | -0.7 °C | 19.56 mm |
| April | -3.1 °C | 8.9 °C | 24.64 mm |
| May | 4.1 °C | 16.9 °C | 66.8 mm |
| June | 10.2 °C | 21.7 °C | 97.54 mm |
| July | 12.7 °C | 24.4 °C | 75.44 mm |
| August | 11.4 °C | 24.6 °C | 66.55 mm |
| September | 6.2 °C | 19.2 °C | 43.43 mm |
| October | -0.9 °C | 10.3 °C | 37.08 mm |
| November | -9.1 °C | 0.4 °C | 20.32 mm |
| December | -16.2 °C | -6.8 °C | 17.53 mm |
| Annual | -2.8 °C | 8.5 °C | 494.03 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 3b : -37.2°C to -34.4°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 |