McGregor, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 27.7 °F (low) to 50.2 °F (high). Annual precipitation averages 16.5 Inches. McGregor 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. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.2 °F | 17.7 °F | 0.5 in. |
| February | 3.0 °F | 22.4 °F | 0.43 in. |
| March | 14.6 °F | 34.5 °F | 0.62 in. |
| April | 27.4 °F | 51.7 °F | 0.82 in. |
| May | 39.3 °F | 64.3 °F | 2.33 in. |
| June | 49.8 °F | 72.7 °F | 3.53 in. |
| July | 54.2 °F | 79.0 °F | 2.75 in. |
| August | 52.2 °F | 80.0 °F | 1.63 in. |
| September | 42.2 °F | 69.7 °F | 1.42 in. |
| October | 29.8 °F | 53.0 °F | 1.23 in. |
| November | 16.4 °F | 35.4 °F | 0.63 in. |
| December | 4.6 °F | 22.3 °F | 0.56 in. |
| Annual | 27.7 °F | 50.2 °F | 16.45 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 3b : -35°F to -30°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |