Hazardous air quality caused by wildfires. Mudslides created by raging thunderstorms. Flash floods through inescapable slot canyons.

The Great Outdoors often requires us to consider the threat of natural disasters — but this summer is exceptionally fraught for those seeking time in nature. Extreme weather has led to dangerous conditions for many national parks, leading to warnings to visitors, or closures of affected areas.

Here are the closures you need to know about if you’re planning a national park vacation anytime soon. And no matter what public lands trips you might have planned, it’s a good idea to check on the conditions. The examples below are only a portion of the many parks and wilderness areas seeing extreme weather.

Black Canyon of the Gunnison National Park

Mountain ride with forests with smoke and fire visible
The fire in 2025; (photo/NPS)

Located in western Colorado, this park saw significant damage in 2025 from a wildfire that reached more than 4,000 acres in size, and it’s continuing to experience weather disruptions in 2026.

On July 16, significant thunderstorms resulted in a major rainfall, triggering three large mudslides on East Portal Road, according to a National Park Service (NPS) press release. The road provides access to many recreation opportunities in the park and in the nearby Curecanti National Recreation Area.

The mudslides trapped 21 visitors at the bottom of the road. Responders were able to safely evacuate everyone, and no injuries were reported. The road, campground, and picnic area remain closed until further notice.

Zion National Park

side by side of river before and after flash flood
Before and after a flash flood in Zion National Park; (photo/NPS, Anne Winters)

Flash floods are a perennial issue at this iconic Utah park.

“Flash floods can occur at any time in Zion National Park and the desert southwest. All narrow canyons are potentially hazardous. Flash floods, often caused by storms miles away, pose real danger and can be life threatening,” the NPS said on the park’s website.

The park’s slot canyons, where visitors traverse through narrow gaps in sandstone created by erosion and flash floods, close whenever the Virgin River’s flow rate surpasses 150 cubic feet per second and when the National Weather Service (NWS) issues a Flash Flood Warning. This includes the extremely popular Narrows slot canyon, which has become such an in-demand hike that the NPS instituted a lottery system.

On Sunday, July 19, the park announced that the criteria were met that necessitated closing the slot canyons. As of July 20, the NWS still lists the flash flood possibility in the park as “probable,” the second-highest level behind “expected.”

North Cascades National Park

dock on a lake with fire in distance
Wildfires, like this one from 2010, are a frequent issue in North Cascades National Park; (photo/NPS)

This remote park in Washington is another one that got walloped by Mother Nature in 2025. Major flooding closed many services and structures in the Stehekin Valley, a major part of the park. It still does not have a working wastewater system. Now the park is facing multiple wildfires. As of July 17, three wildfires are actively burning in the park, according to a NPS press release.

The most serious, the Luna fire, has grown from 7 to 22 acres since July 8. It has resulted in the closure of a portion of the Luna Cross-country Zone and the McMillan Creek drainage area, from the east and southeast aspect of Lunatic Peak down to approximately 2,000 feet in elevation.

This closure comes on top of existing closures from previous wildfires that have left landscapes unstable and hazardous to visitors, which include the Chilliwack and Little Beaver areas and Stetattle Creek Trail.

Other Affected Parks

Many other national park sites — including forests, lakeshores, and wilderness areas — are also warning visitors or issuing closure alerts. Here’s a quick list of other affected parks:

  • Isle Royale National Park: “Ash is falling from the sky,” this national park in Michigan reported this week. Multiple campgrounds have closed, but even day hikes might not be a good idea. Air quality measurements were literally off the charts last week, and still remain “unhealthy,” according to U.S. government air monitors.
  • The Boundary Waters Canoe Area Wilderness: Nearly 20 wildfires burning across Superior National Forest have forced the Forest Service to close the entire Boundary Waters Canoe Area Wilderness in Minnesota. There is no set reopening date.
  • Voyageurs National Park: One of Michigan’s most popular parks, Voyageurs continues to experience “hazardous weather conditions,” according to the park website. “Dry conditions and very strong west winds will cause near critical fire weather conditions today,” park officials said on Monday.


Want to check on a destination before getting in the car? You can use AirNow, a searchable database managed by the U.S. government, to check on air quality for anywhere in the country. If you’re planning on visiting any park — state or national — check the park’s website ahead of time for any potential warnings or closures.