How Crowded Is George Rogers Clark in September?
September is an average month at George Rogers Clark National Historical Park, running about 0.9× the park's average month — roughly 7% of the year's visitors come in September. That puts it between the May peak and the January low. Overall our best-time score rates September as "Excellent" for a visit. Typical September weather averages a high near 82°F and a low around 57°F, with about 3.6" of precipitation. You'll get about 12.2 hours of daylight to explore.
Frequently Asked Questions
September is average at George Rogers Clark National Historical Park (about 0.9× the average month). Our best-time score rates it "Excellent". The single best month overall is October.
The busiest month is May and the quietest is January. September sits at about 0.9× the park's average, or 7% of annual visitation.
Source: National Park Service Visitor Use Statistics (1979–2025), NOAA NCEI Climate Normals 1991–2020. Updated 2026-06-20.