Hammond, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.6 °C (low) to 15.4 °C (high). Annual precipitation averages 1018.5 Millimeters. Hammond 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 | -7.7 °C | 0.4 °C | 57.15 mm |
| February | -6.3 °C | 2.4 °C | 54.86 mm |
| March | -1.3 °C | 8.2 °C | 60.2 mm |
| April | 4.2 °C | 15.1 °C | 95.5 mm |
| May | 10.2 °C | 21 °C | 109.22 mm |
| June | 15.8 °C | 26.4 °C | 118.87 mm |
| July | 18.4 °C | 28.7 °C | 108.46 mm |
| August | 17.6 °C | 27.8 °C | 104.9 mm |
| September | 13.4 °C | 24.6 °C | 84.33 mm |
| October | 6.8 °C | 17.4 °C | 92.46 mm |
| November | 0.9 °C | 9.8 °C | 72.9 mm |
| December | -4.7 °C | 3.2 °C | 59.69 mm |
| Annual | 5.6 °C | 15.4 °C | 1018.54 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 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |