Glacier in September: Crowds, Weather & What to Pack

Best window · VisitWhen score 68/100 · #3 of 12 months

September is one of the best months of the year to visit Glacier National Park: crowds run 73% of the July peak (557,269 average visits). Weather: highs average 63°F and lows 39°F, with 1.6″ of precipitation and 12.6 hours of daylight. Computed from NPS and NOAA data.

Planning Glacier? Pack a guidebook: Moon Glacier National Park on Amazon. · affiliate link, VisitWhen earns from qualifying purchases

Crowds in September

Glacier averages 557,269 recreation visits in September — 73% of what July, the peak month, draws. Trailheads and parking fill accordingly — book early and start days at dawn.

Weather & daylight

Days are mild (highs average 63°F), and mornings are chilly (lows average 39°F). It is typically dry (1.6″ of precipitation). Mid-month daylight runs 12.6 hours.

NOAA 1991–2020 monthly normals, station ST. MARY 1 SSW, MT US (17 mi from park coordinates, 4,555 ft elevation) — conditions vary inside the park, especially with elevation. Daylight computed for the 15th of September.

What to pack for Glacier in September

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

• Warm mid-layer (fleece or light puffy) — mornings average 39°F
• Sturdy broken-in footwear, navigation and a basic first-aid kit — every park, every month
• Bear spray — recommended by the park in grizzly country (check current park regulations before you carry)

As an Amazon Associate, VisitWhen earns from qualifying purchases. Gear names above link to Amazon searches or to a specific product — we don't show or set prices; you always see Amazon's current price.

Packing for a trip with a date on it? Amazon Prime includes fast delivery on eligible items, and eligible new members may be offered a free trial, so gear ordered this week can arrive before you leave. Delivery speed varies by item and address. See if you can try Prime free →
Affiliate link — we may earn a commission on qualifying sign-ups, at no extra cost to you. Current terms are on Amazon's page.

Also at their best in September

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

• 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
• Isle Royale in September — 39% of peak crowds, highs 65°F, score 79/100

Common questions

See also: the best national parks to visit in September · Last verified 2026-09-24