Turtle Lake, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.2 °C (low) to 11.1 °C (high). Annual precipitation averages 454.7 Millimeters. Turtle Lake 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 | -17.2 °C | -6.9 °C | 13.72 mm |
| February | -15.3 °C | -4.4 °C | 10.67 mm |
| March | -8.8 °C | 2.5 °C | 17.02 mm |
| April | -1.8 °C | 11.6 °C | 26.92 mm |
| May | 5.2 °C | 18.7 °C | 66.55 mm |
| June | 11.2 °C | 23.7 °C | 92.46 mm |
| July | 13.9 °C | 27.4 °C | 69.34 mm |
| August | 12.6 °C | 27.3 °C | 52.32 mm |
| September | 7.3 °C | 21.7 °C | 42.67 mm |
| October | 0.2 °C | 12.7 °C | 33.02 mm |
| November | -7.4 °C | 3.2 °C | 15.24 mm |
| December | -13.8 °C | -4.3 °C | 14.73 mm |
| Annual | -1.2 °C | 11.1 °C | 454.66 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 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 |