Indiana Dunes National Park weather in August
August in Indiana Dunes National Park: warm, rainy, with very humid — a great time to visit.
#7 of 12 months in Indiana Dunes National Park · #370 of 604 destinations to visit in August · comfort 74/100 (tier B)
Updated June 2026 · climate normals from ERA5 reanalysis
Indiana Dunes National Park climate normals — August
| Daytime high | 26°C / 78°F | 🌤 warm |
|---|---|---|
| Nighttime low | 21°C / 69°F | |
| Feels like (high) | 28°C / 82°F | |
| Rainfall | 88 mm / 3.5 in | 🌧 rainy |
| Rainy days | 11 days | |
| Humidity | 77% | 💦 very humid |
| Dew point | 18°C / 65°F | |
| Sunshine | 11.5 h/day | |
| Daylight | 13.8 h | |
| Wind | 16 km/h / 10 mph | |
| Air quality (US AQI) | 56 | 🙂 moderate |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
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Indiana Dunes National Park in August — FAQ
- Is August a good time to visit Indiana Dunes National Park?
- August in Indiana Dunes National Park: warm, rainy, with very humid — a great time to visit. It ranks #7 of 12 months for Indiana Dunes National Park on SeasonMap's comfort score (74/100).
- What is the weather like in Indiana Dunes National Park in August?
- In August, Indiana Dunes National Park averages a daily high of 25.7°C and a low of 20.7°C, with about 87.7 mm of rain over roughly 10.6 rainy days.
- What is the air quality in Indiana Dunes National Park in August?
- Indiana Dunes National Park has a mean US Air Quality Index of about 56 in August.