Alamo, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.9 °F (low) to 61.2 °F (high). Annual precipitation averages 43.2 Inches. Alamo is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.8 °F | 34.3 °F | 2.81 in. |
| February | 20.2 °F | 38.3 °F | 2.41 in. |
| March | 29.4 °F | 49.4 °F | 3.1 in. |
| April | 39.9 °F | 61.7 °F | 4.47 in. |
| May | 51.0 °F | 72.4 °F | 4.65 in. |
| June | 60.1 °F | 80.8 °F | 5.05 in. |
| July | 62.8 °F | 83.4 °F | 4.4 in. |
| August | 60.4 °F | 82.2 °F | 3.52 in. |
| September | 52.9 °F | 77.3 °F | 3.18 in. |
| October | 41.8 °F | 65.1 °F | 3.32 in. |
| November | 31.7 °F | 50.5 °F | 3.47 in. |
| December | 23.1 °F | 38.7 °F | 2.82 in. |
| Annual | 40.9 °F | 61.2 °F | 43.2 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |