How Crowded Is Mount Rainier National Park in September?

September runs about 1.7× Mount Rainier National Park's average month, which makes it a very busy month here — roughly 14% of the park's yearly visitors come in September.

In a typical September the park sees about 214,000 recreation visits, based on National Park Service monthly counts from 1979 to 2025.

That makes September the 3rd-busiest of the park's twelve months, sitting between the July peak (3×) and the February low (0.1×).

On our Best Time to Visit score September rates 44/100 ("Poor"), versus the top-rated May at 52/100 — best overall balance of crowds, weather and daylight.

Typical September weather, from 1991–2020 NOAA climate normals at the nearest station, averages a daytime high near 57°F and an overnight low around 41°F, with about 4.4" of precipitation.

That average of about 49°F is cool, so layers and a shorter daylight window matter.

Because June, July and August together draw about 62% of annual visitors, choosing September instead steps outside that summer crush — the single biggest lever on how crowded the park feels.

You'll have about 12.3 hours of daylight in September to explore — between the 8.3-hour midwinter low and the 15.7-hour summer high.

Park-wide, 2025 drew 1,635,342 recreation visits, up 0.9% from 1,620,006 in 2024.

Across the past decade overall visitation has risen about 18.2%, so a September visit is likely to feel busier than it did a few years ago.