Olympic in September: Crowds, Weather & What to Pack
Shoulder · VisitWhen score 59/100 · #7 of 12 months
September is a solid shoulder-season month to visit Olympic National Park: crowds run 67% of the August peak (420,210 average visits), days average 69°F with 12.6 hours of daylight. Computed from NPS and NOAA data.
Crowds in September
Olympic averages 420,210 recreation visits in September — 67% of what August, the peak month, draws. Trailheads and parking fill accordingly.
Weather & daylight
Days are mild (highs average 69°F), and nights stay mild (lows average 49°F). This is one of the wetter months (6.1″ of precipitation on average). Mid-month daylight runs 12.6 hours.
NOAA 1991–2020 monthly normals, station QUINAULT 4 NE, WA US (13 mi from park coordinates, 286 ft elevation) — conditions vary inside the park, especially with elevation. Daylight computed for the 15th of September.
What to pack for Olympic in September
Computed from the month's weather normals above — not a generic list.
- Rain shell + pack cover — 6.1″ 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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If your dates are flexible, consider shifting: The computed best months for Olympic are April and May.
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
Is Olympic crowded in September?
Moderately: September runs 67% of the August peak, averaging 420,210 visits (NPS, 2021–2025).
What is the weather like in Olympic in September?
Average highs of 69°F, lows of 49°F, 6.1″ of precipitation (NOAA 1991–2020 normals, QUINAULT 4 NE, WA US station).
What should I pack for Olympic in September?
Rain shell + pack cover; Sturdy broken-in footwear, navigation and a basic first-aid kit — the full weather-computed list is on this page.
See also: the best national parks to visit in September · Last verified 2026-09-12