Travelers' information station

A travelers' information station (TIS), also called highway advisory radio (HAR) by the United States Department of Transportation, is a licensed low-powered non-commercial radio station, used to broadcast information to the general public, including for motorists regarding travel, destinations of interest, and situations of imminent danger and emergencies. They are commonly operated by transportation departments, national and local parks departments and historic sites, airport authorities, local governments, federal agencies, colleges and universities, hospitals and health agencies, and for special events and destinations.

TIS notification sign in the United States