Plain Dealing, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.7 °C (low) to 24.5 °C (high). Annual precipitation averages 1358.9 Millimeters. Plain Dealing is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.3 °C | 13.6 °C | 114.81 mm |
| February | 2.9 °C | 15.8 °C | 117.09 mm |
| March | 6.8 °C | 20.2 °C | 136.91 mm |
| April | 10.9 °C | 24.6 °C | 122.17 mm |
| May | 16.3 °C | 28.4 °C | 116.59 mm |
| June | 20.6 °C | 32.2 °C | 121.92 mm |
| July | 22.3 °C | 34.1 °C | 89.66 mm |
| August | 21.8 °C | 34.4 °C | 88.14 mm |
| September | 18.3 °C | 31.2 °C | 91.44 mm |
| October | 11.5 °C | 25.4 °C | 125.73 mm |
| November | 5.9 °C | 19.1 °C | 106.17 mm |
| December | 2.3 °C | 14.6 °C | 128.27 mm |
| Annual | 11.7 °C | 24.5 °C | 1358.9 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |