Courtenay, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 30.4 °F (low) to 51.2 °F (high). Annual precipitation averages 20.2 Inches. Courtenay is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.2 °F | 17.7 °F | 0.47 in. |
| February | 3.9 °F | 22.4 °F | 0.45 in. |
| March | 15.9 °F | 34.9 °F | 0.71 in. |
| April | 29.5 °F | 52.0 °F | 1.07 in. |
| May | 42.6 °F | 66.1 °F | 2.85 in. |
| June | 53.9 °F | 75.4 °F | 3.63 in. |
| July | 58.1 °F | 80.5 °F | 3.75 in. |
| August | 55.2 °F | 79.8 °F | 2.44 in. |
| September | 45.9 °F | 70.9 °F | 2.15 in. |
| October | 33.2 °F | 55.0 °F | 1.59 in. |
| November | 19.2 °F | 37.1 °F | 0.61 in. |
| December | 7.1 °F | 23.1 °F | 0.52 in. |
| Annual | 30.4 °F | 51.2 °F | 20.24 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |