Mecca, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.2 °C (low) to 17.7 °C (high). Annual precipitation averages 1105.9 Millimeters. Mecca is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.8 °C | 2.2 °C | 75.18 mm |
| February | -5.1 °C | 5 °C | 64.52 mm |
| March | 0.1 °C | 11.2 °C | 83.57 mm |
| April | 5.8 °C | 18.5 °C | 117.35 mm |
| May | 11.7 °C | 24.2 °C | 117.09 mm |
| June | 16.7 °C | 28.8 °C | 125.22 mm |
| July | 18.3 °C | 30.3 °C | 109.73 mm |
| August | 17.1 °C | 29.6 °C | 82.3 mm |
| September | 12.8 °C | 26.6 °C | 79.25 mm |
| October | 6.6 °C | 19.9 °C | 93.22 mm |
| November | 0.9 °C | 11.4 °C | 86.61 mm |
| December | -3.9 °C | 4.8 °C | 71.88 mm |
| Annual | 6.2 °C | 17.7 °C | 1105.92 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |