New Harmony, Indiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 8 °C (low) to 19.3 °C (high). Annual precipitation averages 1173.5 Millimeters. New Harmony is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.2 °C | 4.8 °C | 90.68 mm |
| February | -2.7 °C | 7.7 °C | 73.66 mm |
| March | 1.9 °C | 13.2 °C | 107.7 mm |
| April | 7.7 °C | 19.7 °C | 120.9 mm |
| May | 13.6 °C | 25 °C | 134.11 mm |
| June | 18.3 °C | 29.7 °C | 112.01 mm |
| July | 20 °C | 31.2 °C | 106.93 mm |
| August | 18.8 °C | 30.7 °C | 77.22 mm |
| September | 14.4 °C | 27.8 °C | 82.55 mm |
| October | 8.1 °C | 21.3 °C | 85.34 mm |
| November | 2.3 °C | 13.4 °C | 95 mm |
| December | -2.1 °C | 7.2 °C | 87.38 mm |
| Annual | 8 °C | 19.3 °C | 1173.48 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |