Henryetta, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 9.6 °C (low) to 22.4 °C (high). Annual precipitation averages 1114.5 Millimeters. Henryetta is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -2.6 °C | 10.1 °C | 53.34 mm |
| February | -0.6 °C | 12.4 °C | 54.1 mm |
| March | 4.4 °C | 17.5 °C | 84.33 mm |
| April | 8.9 °C | 22.2 °C | 112.78 mm |
| May | 14.6 °C | 26.1 °C | 145.54 mm |
| June | 19.6 °C | 30.9 °C | 120.65 mm |
| July | 21.4 °C | 33.8 °C | 103.12 mm |
| August | 20.8 °C | 33.9 °C | 80.26 mm |
| September | 16.2 °C | 29.8 °C | 112.78 mm |
| October | 9.8 °C | 23.7 °C | 101.85 mm |
| November | 3.9 °C | 17.1 °C | 80.26 mm |
| December | -0.9 °C | 11.3 °C | 65.53 mm |
| Annual | 9.6 °C | 22.4 °C | 1114.54 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |