Yellowstone · September
Yellowstone in September
September is a busy time to visit Yellowstone — quieter than August, busier than October.
Crowd score
How busy it gets
Approaching peak season — expect full lots by mid-morning and busy overlooks.
About 63% of this park's busiest month.
Source: NPS Visitor Use Statistics, 2023–2025
Data: NPS visitation 2023–2025 · crowd scores computed Jul 2026 · alerts checked Jul 10, 2026. How this is calculated →
Computed from federal data · Methodology by Sharon Ben-Moshe
Visitation
Typical September visits vs. the year
Typical monthly recreation visits, averaged over the most recent three full years.
Source: NPS Visitor Use Statistics, 2023–2025
Weather
September weather
- Avg high
- 68°F
- Avg low
- 37°F
- Precipitation
- 1.4"
- Sunrise
- 6:01 AM
- Sunset
- 6:32 PM
- Daylight
- 12.5h
Source: NOAA 1991–2020 climate normals, Yellowstone (Lake Yellowstone)
What's open
Yellowstone in September: access
Open 24 hours in season; most roads close to cars early Nov to late Apr
Seasonal closures may apply:
- Road Closure
Seasonal road closures in effect
Most park roads are closed to regular vehicles between early November and late April. Check current road status before traveling.
Details on nps.gov → - Park Closure
Biscuit Basin Closed Due to Hydrothermal Explosion
The parking lot, boardwalk, and Firehole River at Biscuit Basin, located north of Old Faithful, is closed to all travel until further notice due to the possibility of another event at the site of a hydrothermal explosion that occurred July 23, 2024.
Details on nps.gov → - Information
Select rivers closed to fishing daily, 2 p.m. to sunrise
The following rivers and their tributaries will close daily from 2 p.m. to sunrise due to warm water temperatures and low flows: Madison River, Firehole River, and Gibbon River.
Details on nps.gov →
Source: NPS Data API
Conditions
Current alerts
- Road Closure
Seasonal road closures in effect
Most park roads are closed to regular vehicles between early November and late April. Check current road status before traveling.
Details on nps.gov → - Information
Vehicle Entrance Reservation Not Needed
Although an entrance pass is required to enter Yellowstone National Park, vehicle reservations are not needed. You are encouraged to purchase an entrance pass before arriving, but you may also purchase passes at any entrance station upon arrival.
Details on nps.gov → - Information
Traffic Delays - Gardner River High Bridge
Expect a single lane of traffic with up to 15-minute delays, 24 hours a day, seven days a week, from April 1 through late October 2026. Oversized/overweight vehicles (8'6"+ wide, 75'+ long, 80,000 lbs+ gross vehicle weight) will not be able to cross the bridge during this time.
Details on nps.gov → - Park Closure
Biscuit Basin Closed Due to Hydrothermal Explosion
The parking lot, boardwalk, and Firehole River at Biscuit Basin, located north of Old Faithful, is closed to all travel until further notice due to the possibility of another event at the site of a hydrothermal explosion that occurred July 23, 2024.
Details on nps.gov → - Information
Traffic Delays - Gibbon River Bridge
Expect up to 15-minute delays on Gibbon River Bridge from July 9 through late-July while crews repair the railing.
Details on nps.gov → - Information
Select rivers closed to fishing daily, 2 p.m. to sunrise
The following rivers and their tributaries will close daily from 2 p.m. to sunrise due to warm water temperatures and low flows: Madison River, Firehole River, and Gibbon River.
Details on nps.gov →
Source: NPS Data API
Context
Yellowstone crowds across the year
Alternatives
Quieter nearby in September
FAQ
Yellowstone in September
How busy is Yellowstone in September?
September rates 7/10 for crowds (Busy) at Yellowstone National Park — about 63% of its busiest month. Typical recreation visits: 660,153.
What is the weather like at Yellowstone in September?
In September, Yellowstone averages a high of 68°F and a low of 37°F, with about 1.4 inches of precipitation.