Thompson, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1 °C (low) to 10.1 °C (high). Annual precipitation averages 582.4 Millimeters. Thompson 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 | -19.1 °C | -9.3 °C | 15.49 mm |
| February | -17 °C | -6.6 °C | 14.48 mm |
| March | -9.2 °C | 0.6 °C | 22.35 mm |
| April | -0.9 °C | 10.7 °C | 27.94 mm |
| May | 6.2 °C | 18.8 °C | 74.42 mm |
| June | 12.6 °C | 24.1 °C | 103.63 mm |
| July | 14.6 °C | 26.6 °C | 90.42 mm |
| August | 12.9 °C | 26.3 °C | 76.45 mm |
| September | 7.9 °C | 21.3 °C | 66.8 mm |
| October | 1.1 °C | 12.4 °C | 49.53 mm |
| November | -7 °C | 2.3 °C | 21.08 mm |
| December | -14.5 °C | -6 °C | 19.81 mm |
| Annual | -1 °C | 10.1 °C | 582.4 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 | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |