Seward, Kansas has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.9 °C (low) to 19.9 °C (high). Annual precipitation averages 694.7 Millimeters. Seward is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.8 °C | 6.1 °C | 19.05 mm |
| February | -4.3 °C | 8.6 °C | 24.64 mm |
| March | 0.8 °C | 14.2 °C | 46.23 mm |
| April | 5.8 °C | 19.4 °C | 58.93 mm |
| May | 11.9 °C | 24.7 °C | 114.05 mm |
| June | 17.7 °C | 30.8 °C | 95.5 mm |
| July | 20 °C | 33.2 °C | 92.46 mm |
| August | 18.9 °C | 32.2 °C | 89.92 mm |
| September | 14.6 °C | 28.2 °C | 49.28 mm |
| October | 7.2 °C | 21.3 °C | 53.85 mm |
| November | 0.3 °C | 13.6 °C | 27.18 mm |
| December | -4.7 °C | 6.9 °C | 23.62 mm |
| Annual | 6.9 °C | 19.9 °C | 694.71 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |