Quick Midwest hop — dune climbing on Lake Michigan, waterfalls and rail trail in the Cuyahoga Valley. Early September in the Great Lakes region typically brings warm, humid late-summer conditions: highs upper 70s to low 80s°F at both parks with overnight lows low-to-mid 60s, and a moderate chance of afternoon thunderstorms. Lake Michigan water at Indiana Dunes is usually still warm enough for swimming. Humidity will be noticeable on longer hikes and bike rides — plan strenuous activity for morning hours.
Quick Midwest hop — dune climbing on Lake Michigan, waterfalls and rail trail in the Cuyahoga Valley. Early September in the Great Lakes region typically brings warm, humid late-summer conditions: highs upper 70s to low 80s°F at both parks with overnight lows low-to-mid 60s, and a moderate chance of afternoon thunderstorms. Lake Michigan water at Indiana Dunes is usually still warm enough for swimming. Humidity will be noticeable on longer hikes and bike rides — plan strenuous activity for morning hours.