Indiana Dunes National Park in September
In September, Indiana Dunes National Park averages a high of 74°F and a low of 56°F, with 3.6 inches of precipitation (rain plus melted snow). About 248,000 people visit, the 5th busiest of 12 (moderate). Days are 12 hours 25 minutes long.
- Quiet
- Moderate
- Busy
- Very busy
- Few or no visits (may be closed)
- Best months
- High / low
- 74° / 56°F
- Precipitation
- 3.6in
- Snow
- 0in
- Daylight
- 12h 25m
- Visitors
- 248,000
- Crowds
- Moderate
Best months for weather and crowds instead: April (moderate).
Weather 1991–2020 averages at Indiana Dunes Nl, IN, 3.4 miles from the park's center, 680 ft. Visitors National Park Service recreation visits, average of 2023–2025. Updated .
Other parks in September
| Park | High / low °F | Crowds | Weather |
|---|---|---|---|
| Sleeping Bear Dunes National Lakeshore | 69° / 52° | Moderate | Mild, wet |
| Gateway Arch National Park | 81° / 57° | Moderate | Hot |
| Cuyahoga Valley National Park | 74° / 52° | Busy | Mild, wet |
| Mammoth Cave National Park | 85° / 60° | Busy | Hot |
| Ozark National Scenic Riverways | 81° / 54° | Busy | Hot |
Closures, reservations and alerts: Indiana Dunes National Park on nps.gov
All twelve months at Indiana Dunes · National parks to visit in September