Montpelier, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.2 °C (low) to 25.8 °C (high). Annual precipitation averages 1698.8 Millimeters. Montpelier 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 | 3.9 °C | 16.5 °C | 165.61 mm |
| February | 5.8 °C | 18.7 °C | 136.65 mm |
| March | 9.2 °C | 22.3 °C | 139.19 mm |
| April | 12.5 °C | 25.7 °C | 138.43 mm |
| May | 16.9 °C | 29.7 °C | 142.24 mm |
| June | 20.7 °C | 32.3 °C | 174.5 mm |
| July | 21.9 °C | 33.2 °C | 155.45 mm |
| August | 21.8 °C | 33.5 °C | 170.94 mm |
| September | 19.3 °C | 31.7 °C | 116.84 mm |
| October | 13.2 °C | 27 °C | 111.25 mm |
| November | 7.7 °C | 21.4 °C | 105.66 mm |
| December | 4.9 °C | 17.6 °C | 141.99 mm |
| Annual | 13.2 °C | 25.8 °C | 1698.75 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 |