How Crowded Is Hawaiʻi Volcanoes National Park in September?

September runs about 0.8× Hawaiʻi Volcanoes National Park's average month, which makes it a quiet month here — roughly 7% of the park's yearly visitors come in September.

In a typical September the park sees about 100,000 recreation visits, based on National Park Service monthly counts from 1979 to 2025.

It is the quietest month of the year at Hawaiʻi Volcanoes; by contrast January, the busiest, runs about 1.2× the average — so September is the easiest time to have the place largely to yourself.

On our Best Time to Visit score September rates 79/100 ("Excellent") — the single best-rated month at Hawaiʻi Volcanoes, balancing crowds against weather and daylight.

Typical September weather, from 1991–2020 NOAA climate normals at the nearest station, averages a daytime high near 84°F and an overnight low around 70°F, with about 2.8" of precipitation.

That average of about 77°F is warm enough that midday heat is worth planning around.

Because June, July and August together draw about 25% 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 12.1 hours of daylight in September to explore — between the 10.8-hour midwinter low and the 13.2-hour summer high.

Park-wide, 2025 drew 1,877,854 recreation visits, up 31% from 1,433,593 in 2024.

Across the past decade overall visitation has risen about 11.4%, so a September visit is likely to feel busier than it did a few years ago.