Climate almanac
Grissom Air Force Base
Indiana, United States · 40.66°, -86.15°
What is the climate like in Grissom Air Force Base?
The best time to visit Grissom Air Force Base is typically August – September, with trip comfort peaking in September (7.5/10). Grissom Air Force Base is warmest in July, when daily highs average 84°F (29°C), and coolest in January, when lows fall to about 23°F (-5°C). The wettest month is typically May and the driest is September; the year sees roughly 42 in (1063 mm) of precipitation.
- Best time to visitAugust – September — comfort peaks in September (7.5/10)
- Warmest monthJuly — average high 84°F (29°C)
- Coolest monthJanuary — average low 23°F (-5°C)
- Wettest monthMay (5.0 in (128 mm))
- Driest monthSeptember (2.4 in (61 mm))
- Annual precipitation42 in (1063 mm)
- Based on2016-2025 daily ERA5 reanalysis data (10-year normals)
- Records fromPeru Grissom AFB, 1 km away (1956-2026)