Prospect, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.9 °C (low) to 25.2 °C (high). Annual precipitation averages 1532.6 Millimeters. Prospect is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.1 °C | 15 °C | 150.11 mm |
| February | 4.9 °C | 17.2 °C | 131.06 mm |
| March | 8.7 °C | 21.4 °C | 145.8 mm |
| April | 12.5 °C | 25.2 °C | 153.16 mm |
| May | 17.3 °C | 29.1 °C | 121.16 mm |
| June | 21 °C | 32.2 °C | 124.21 mm |
| July | 22.3 °C | 33.6 °C | 113.28 mm |
| August | 22 °C | 33.9 °C | 113.03 mm |
| September | 19 °C | 31.4 °C | 99.06 mm |
| October | 12.8 °C | 26.6 °C | 108.2 mm |
| November | 7.2 °C | 20.3 °C | 128.27 mm |
| December | 4.2 °C | 15.9 °C | 145.29 mm |
| Annual | 12.9 °C | 25.2 °C | 1532.63 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |