Milfay, Oklahoma has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8.8 °C (low) to 22.2 °C (high). Annual precipitation averages 1005.3 Millimeters. Milfay 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 | -3.4 °C | 9.9 °C | 38.35 mm |
| February | -1.6 °C | 12.2 °C | 45.97 mm |
| March | 3.3 °C | 17.3 °C | 74.17 mm |
| April | 8.2 °C | 22.2 °C | 103.12 mm |
| May | 13.8 °C | 26.1 °C | 140.72 mm |
| June | 18.8 °C | 30.8 °C | 124.97 mm |
| July | 21 °C | 33.8 °C | 86.36 mm |
| August | 20.1 °C | 33.7 °C | 82.04 mm |
| September | 15.6 °C | 29.4 °C | 93.73 mm |
| October | 8.9 °C | 23.4 °C | 100.08 mm |
| November | 3.1 °C | 16.8 °C | 64.26 mm |
| December | -1.9 °C | 10.7 °C | 51.56 mm |
| Annual | 8.8 °C | 22.2 °C | 1005.33 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 75-100 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 |