Herndon, Kansas has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3 °C (low) to 18.8 °C (high). Annual precipitation averages 527.3 Millimeters. Herndon is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.6 °C | 5.2 °C | 10.67 mm |
| February | -8.2 °C | 7 °C | 14.99 mm |
| March | -3.6 °C | 13.1 °C | 25.65 mm |
| April | 1.6 °C | 18.1 °C | 51.82 mm |
| May | 8 °C | 23.4 °C | 76.96 mm |
| June | 14.1 °C | 29.8 °C | 75.44 mm |
| July | 17.3 °C | 32.8 °C | 84.07 mm |
| August | 15.9 °C | 31.4 °C | 73.91 mm |
| September | 10.4 °C | 27.2 °C | 42.16 mm |
| October | 2.7 °C | 19.7 °C | 38.35 mm |
| November | -4.2 °C | 12 °C | 18.29 mm |
| December | -8.8 °C | 5.8 °C | 14.99 mm |
| Annual | 3 °C | 18.8 °C | 527.3 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |