Glenwood, Arkansas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.6 °C (low) to 22.7 °C (high). Annual precipitation averages 1477.8 Millimeters. Glenwood is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.3 °C | 11.1 °C | 100.84 mm |
| February | 0.3 °C | 13.5 °C | 106.93 mm |
| March | 4.2 °C | 18.1 °C | 137.41 mm |
| April | 8.7 °C | 22.8 °C | 146.05 mm |
| May | 14.3 °C | 26.6 °C | 169.42 mm |
| June | 18.8 °C | 31 °C | 107.7 mm |
| July | 20.7 °C | 33.2 °C | 106.68 mm |
| August | 20 °C | 33.2 °C | 87.12 mm |
| September | 16 °C | 29.6 °C | 110.74 mm |
| October | 9.3 °C | 23.8 °C | 134.62 mm |
| November | 3.7 °C | 17.2 °C | 128.78 mm |
| December | 0 °C | 12.3 °C | 141.48 mm |
| Annual | 9.6 °C | 22.7 °C | 1477.77 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : -12.2°C to -9.4°C |
| Plant Hardiness Zone - 2012 | Zone 7b : -15°C to -12.2°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |