Grand Teton in September: Crowds, Weather & What to Pack
Peak crowds · VisitWhen score 67/100 · #5 of 12 months
September is peak season — expect the year's biggest crowds at Grand Teton National Park: crowds run 77% of the July peak (564,320 average visits). Weather: highs average 66°F and lows 34°F, with 1.6″ of precipitation and 12.6 hours of daylight. Computed from NPS and NOAA data.
Planning Grand Teton? Pack a guidebook: Moon Best of Yellowstone & Grand Teton on Amazon. · affiliate link, VisitWhen earns from qualifying purchases
Bring for Grand Teton in September
- Warm mid-layer (fleece or light puffy)See it on AmazonWhy: mornings average 34°F.
- Bear spraySee it on AmazonWhy: recommended by the park in grizzly country (check current park regulations before you carry).
Affiliate links: VisitWhen earns from qualifying purchases, at no extra cost to you. Prices can change; Amazon shows the current one.
Crowds in September
Grand Teton averages 564,320 recreation visits in September — 77% 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 66°F), and mornings are chilly (lows average 34°F). It is typically dry (1.6″ of precipitation). Mid-month daylight runs 12.6 hours.
NOAA 1991–2020 monthly normals, station MORAN 5WNW, WY US (6 mi from park coordinates, 6,805 ft elevation) — conditions vary inside the park, especially with elevation. Daylight computed for the 15th of September.
What to pack for Grand Teton in September
Computed from the month's weather normals above — not a generic list.
- Warm mid-layer (fleece or light puffy) — mornings average 34°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.
If your dates are flexible, consider shifting: The computed best months for Grand Teton are April and May.
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
Is Grand Teton crowded in September?
Yes — September runs 77% of Grand Teton's peak, averaging 564,320 recreation visits (NPS, 2021–2025).
What is the weather like in Grand Teton in September?
Average highs of 66°F, lows of 34°F, 1.6″ of precipitation (NOAA 1991–2020 normals, MORAN 5WNW, WY US station).
What should I pack for Grand Teton in September?
Warm mid-layer (fleece or light puffy); Sturdy broken-in footwear, navigation and a basic first-aid kit; Bear spray — the full weather-computed list is on this page.
See also: the best national parks to visit in September · Last verified 2026-09-24