Seward, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.3 °C (low) to 16.9 °C (high). Annual precipitation averages 746.8 Millimeters. Seward is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.2 °C | 1.1 °C | 17.02 mm |
| February | -7.8 °C | 3.9 °C | 20.07 mm |
| March | -2.5 °C | 10.7 °C | 39.88 mm |
| April | 3.6 °C | 17.2 °C | 69.34 mm |
| May | 10.1 °C | 23.1 °C | 124.97 mm |
| June | 16.1 °C | 28.4 °C | 117.86 mm |
| July | 18.4 °C | 30.5 °C | 87.38 mm |
| August | 17.1 °C | 29.6 °C | 94.74 mm |
| September | 11.8 °C | 25.9 °C | 65.02 mm |
| October | 4.7 °C | 19 °C | 55.12 mm |
| November | -2.4 °C | 10.3 °C | 32.77 mm |
| December | -7.8 °C | 3.2 °C | 22.61 mm |
| Annual | 4.3 °C | 16.9 °C | 746.78 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |