Hazelton, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.7 °C (low) to 11.6 °C (high). Annual precipitation averages 506.5 Millimeters. Hazelton is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -16.6 °C | -6.3 °C | 10.41 mm |
| February | -14.6 °C | -3.7 °C | 12.7 mm |
| March | -8.2 °C | 3.3 °C | 20.32 mm |
| April | -1.4 °C | 11.9 °C | 34.54 mm |
| May | 5.5 °C | 18.9 °C | 71.37 mm |
| June | 11.4 °C | 24 °C | 91.44 mm |
| July | 14.3 °C | 27.7 °C | 87.38 mm |
| August | 12.9 °C | 27.3 °C | 59.94 mm |
| September | 7.8 °C | 22.3 °C | 43.43 mm |
| October | 0.6 °C | 13.2 °C | 45.97 mm |
| November | -7.2 °C | 3.9 °C | 13.46 mm |
| December | -13.2 °C | -3.5 °C | 15.49 mm |
| Annual | -0.7 °C | 11.6 °C | 506.45 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°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 |