Riverdale, North Dakota has a Humid Continental Mild Summer With Dry Winters climate (Köppen classification: Dwb). Average annual temperatures range from -1 °C (low) to 11 °C (high). Annual precipitation averages 454.1 Millimeters. Riverdale 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 | -16.9 °C | -6.8 °C | 11.68 mm |
| February | -15.2 °C | -4.4 °C | 8.38 mm |
| March | -8.6 °C | 2.6 °C | 15.24 mm |
| April | -1.8 °C | 11.3 °C | 29.46 mm |
| May | 5.2 °C | 18.4 °C | 70.36 mm |
| June | 11.3 °C | 23.3 °C | 95.25 mm |
| July | 13.9 °C | 27.1 °C | 68.83 mm |
| August | 12.7 °C | 27.2 °C | 52.58 mm |
| September | 7.4 °C | 21.4 °C | 41.4 mm |
| October | 0.2 °C | 12.6 °C | 34.8 mm |
| November | -7.2 °C | 3.3 °C | 14.48 mm |
| December | -13.5 °C | -4.1 °C | 11.68 mm |
| Annual | -1 °C | 11 °C | 454.14 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 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 | Normal |
| Köppen Climate Classification | Dwb - Humid Continental Mild Summer With Dry Winters |