Hannah, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 27.1 °F (low) to 47.5 °F (high). Annual precipitation averages 20.6 Inches. Hannah is located in USDA Plant Hardiness Zone 3b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.4 °F | 13.0 °F | 0.58 in. |
| February | -1.3 °F | 17.9 °F | 0.62 in. |
| March | 11.9 °F | 29.8 °F | 0.77 in. |
| April | 27.5 °F | 48.6 °F | 1.03 in. |
| May | 39.8 °F | 63.6 °F | 2.69 in. |
| June | 51.0 °F | 72.5 °F | 3.98 in. |
| July | 54.9 °F | 77.2 °F | 3.13 in. |
| August | 52.5 °F | 77.1 °F | 2.73 in. |
| September | 43.8 °F | 68.1 °F | 1.95 in. |
| October | 30.8 °F | 51.6 °F | 1.48 in. |
| November | 16.0 °F | 32.7 °F | 0.86 in. |
| December | 2.4 °F | 18.4 °F | 0.78 in. |
| Annual | 27.1 °F | 47.5 °F | 20.6 in. |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| 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 |