Hawaiʻi Volcanoes in September: Crowds, Weather & What to Pack

Peak crowds · VisitWhen score 51/100 · #3 of 12 months

September is peak season — expect the year's biggest crowds at Hawaiʻi Volcanoes National Park: crowds run 77% of the December peak (116,627 average visits), days average 78°F with 12.3 hours of daylight. Computed from NPS and NOAA data.

Crowds in September

Hawaiʻi Volcanoes averages 116,627 recreation visits in September — 77% of what December, the peak month, draws — the third-quietest month of the year. That crowd level sets the tone for parking, permits and lodging — book early and start days at dawn.

Weather & daylight

Days are pleasant (highs average 78°F), and nights stay mild (lows average 61°F). This is one of the wetter months (16.1″ of precipitation on average). Mid-month daylight runs 12.3 hours.

NOAA 1991–2020 monthly normals, station GLENWOOD #2 55.4, HI US (8 mi from park coordinates, 2,200 ft elevation) — conditions vary inside the park, especially with elevation. Daylight computed for the 15th of September.

What to pack for Hawaiʻi Volcanoes in September

Computed from the month's weather normals above — not a generic list.

• Rain shell + pack cover — 16.1″ of precipitation is normal this month
• Sturdy broken-in footwear, navigation and a basic first-aid kit — every park, every month

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Want quieter or kinder conditions? The computed best month for Hawaiʻi Volcanoes is April.

Also at their best in September

Other parks whose computed September verdict is a best window — same NPS × NOAA formula:

• Big Bend in September — 26% of peak crowds, highs 79°F, score 84/100
• Wrangell–St. Elias in September — 25% of peak crowds, highs 56°F, score 84/100
• Guadalupe Mountains in September — 35% of peak crowds, highs 80°F, score 81/100
• Gateway Arch in September — 29% of peak crowds, highs 81°F, score 80/100

Common questions

See also: the best national parks to visit in September · Last verified 2026-09-12