Grenola, Kansas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.5 °C (low) to 20.4 °C (high). Annual precipitation averages 1015.2 Millimeters. Grenola is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.6 °C | 6.8 °C | 25.65 mm |
| February | -3.8 °C | 9.4 °C | 39.88 mm |
| March | 1.3 °C | 15.1 °C | 70.1 mm |
| April | 6.9 °C | 20.4 °C | 101.6 mm |
| May | 13 °C | 24.8 °C | 149.1 mm |
| June | 18.3 °C | 29.7 °C | 150.88 mm |
| July | 20.7 °C | 32.7 °C | 102.62 mm |
| August | 19.6 °C | 32.4 °C | 101.09 mm |
| September | 14.8 °C | 28.2 °C | 89.92 mm |
| October | 7.8 °C | 21.9 °C | 86.36 mm |
| November | 1.5 °C | 14.7 °C | 55.37 mm |
| December | -4.1 °C | 8.2 °C | 42.67 mm |
| Annual | 7.5 °C | 20.4 °C | 1015.24 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |