Jansen, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.7 °C (low) to 17.5 °C (high). Annual precipitation averages 786.4 Millimeters. Jansen is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.4 °C | 2.1 °C | 18.03 mm |
| February | -7.4 °C | 4.7 °C | 22.35 mm |
| March | -1.9 °C | 11.5 °C | 41.66 mm |
| April | 3.6 °C | 17.6 °C | 73.41 mm |
| May | 10.3 °C | 23.2 °C | 122.94 mm |
| June | 16.2 °C | 28.7 °C | 115.82 mm |
| July | 18.6 °C | 31.2 °C | 106.43 mm |
| August | 17.4 °C | 30.1 °C | 87.12 mm |
| September | 12.3 °C | 26.2 °C | 78.99 mm |
| October | 5.2 °C | 19.2 °C | 57.4 mm |
| November | -1.9 °C | 11 °C | 35.31 mm |
| December | -7.1 °C | 4.2 °C | 26.92 mm |
| Annual | 4.7 °C | 17.5 °C | 786.38 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |