Calvin, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.4 °C (low) to 25.1 °C (high). Annual precipitation averages 1499.4 Millimeters. Calvin 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 | 2.5 °C | 14.6 °C | 146.3 mm |
| February | 4.1 °C | 16.8 °C | 126.49 mm |
| March | 7.8 °C | 21.3 °C | 137.41 mm |
| April | 11.9 °C | 25.3 °C | 148.34 mm |
| May | 16.7 °C | 29.2 °C | 122.94 mm |
| June | 20.7 °C | 32.6 °C | 122.17 mm |
| July | 22.2 °C | 33.9 °C | 113.03 mm |
| August | 21.7 °C | 34.2 °C | 95.25 mm |
| September | 18.3 °C | 31.6 °C | 90.42 mm |
| October | 12.2 °C | 26.4 °C | 115.57 mm |
| November | 6.7 °C | 20.1 °C | 127.76 mm |
| December | 3.4 °C | 15.6 °C | 153.67 mm |
| Annual | 12.4 °C | 25.1 °C | 1499.35 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 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |