The National Park Service posts alerts on park pages in four types. The type is supposed to signal severity, but in practice the wording matters more than the label — a closure sometimes gets filed under "Information." Here's what each is meant to mean, and how we read it.
Danger
An imminent or serious hazard: flash flooding, rockfall, dangerous water, an active incident. If a Danger alert covers where you're headed, take it at face value and change plans.
Closure
Something is inaccessible — a road, trail, area, campground, or occasionally the whole park. Closures are the alerts that most often change a trip, which is why our status logic weighs them most heavily.
Caution
A situation to be aware of but not an outright barrier: rough conditions, limited services, fire restrictions, wildlife activity. Worth reading, rarely a dealbreaker.
Information
General notices: events, temporary service changes, construction notes, seasonal reminders. Usually low-stakes — but because the NPS sometimes files real closures here, we read the text of every alert rather than trusting the type alone.