Welch, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.3 °C (low) to 20.6 °C (high). Annual precipitation averages 1158.5 Millimeters. Welch 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 | -4.3 °C | 7.4 °C | 46.23 mm |
| February | -2.3 °C | 10 °C | 49.02 mm |
| March | 2.5 °C | 15.3 °C | 84.84 mm |
| April | 7.7 °C | 20.5 °C | 120.9 mm |
| May | 13.3 °C | 24.8 °C | 178.56 mm |
| June | 18.6 °C | 29.7 °C | 133.1 mm |
| July | 20.8 °C | 32.4 °C | 102.36 mm |
| August | 19.7 °C | 32.4 °C | 96.01 mm |
| September | 15.2 °C | 28.2 °C | 110.74 mm |
| October | 8.5 °C | 21.9 °C | 98.81 mm |
| November | 2.4 °C | 15.2 °C | 76.45 mm |
| December | -2.4 °C | 8.9 °C | 61.47 mm |
| Annual | 8.3 °C | 20.6 °C | 1158.49 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 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 |