Cathay, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 29.8 °F (low) to 51 °F (high). Annual precipitation averages 19.8 Inches. Cathay 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 | -0.0 °F | 17.9 °F | 0.46 in. |
| February | 3.4 °F | 22.3 °F | 0.48 in. |
| March | 15.6 °F | 34.6 °F | 0.68 in. |
| April | 28.9 °F | 51.6 °F | 1.14 in. |
| May | 41.9 °F | 65.7 °F | 2.65 in. |
| June | 53.1 °F | 74.8 °F | 3.81 in. |
| July | 57.3 °F | 80.0 °F | 3.32 in. |
| August | 54.4 °F | 79.8 °F | 2.42 in. |
| September | 45.5 °F | 70.8 °F | 1.92 in. |
| October | 32.5 °F | 54.5 °F | 1.65 in. |
| November | 18.5 °F | 36.7 °F | 0.65 in. |
| December | 6.2 °F | 22.8 °F | 0.65 in. |
| Annual | 29.8 °F | 51 °F | 19.83 in. |
| 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 : -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 |