Sweetwater, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.1 °C (low) to 22.5 °C (high). Annual precipitation averages 613.7 Millimeters. Sweetwater is located in USDA Plant Hardiness Zone 7b. 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 | -3.8 °C | 10.3 °C | 16.26 mm |
| February | -2.3 °C | 12.3 °C | 22.86 mm |
| March | 2.3 °C | 17.6 °C | 40.39 mm |
| April | 6.9 °C | 22.3 °C | 55.88 mm |
| May | 12.7 °C | 27 °C | 95.76 mm |
| June | 18.1 °C | 31.7 °C | 87.12 mm |
| July | 20.3 °C | 34.6 °C | 64.77 mm |
| August | 19.6 °C | 34.2 °C | 61.72 mm |
| September | 15.4 °C | 29.7 °C | 59.94 mm |
| October | 8.5 °C | 23.3 °C | 53.09 mm |
| November | 1.9 °C | 16.6 °C | 30.73 mm |
| December | -3 °C | 10.8 °C | 25.15 mm |
| Annual | 8.1 °C | 22.5 °C | 613.67 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 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |