The National Weather Service in Mobile is warning of the potential for “life-threatening” rip currents along Alabama’s beaches through the weekend and for much of next week, fueled by Tropical Storm Beryl’s churn through the central Gulf of Mexico.

Visitors to beaches from Dauphin Island through the Florida Panhandle are advised to heed the beach flag warning system and follow lifeguard instructions. In Florida, beaches remain closed in Panama City Beach after double red flags were hoisted Friday.

A rip current is a powerful channel of water flowing away from shore. A high-risk warning means the surf zone is dangerous for all levels of swimmers, and the weather service advises swimmers to stay out of the water.

The warning echoes advice Friday from Stephen Leatherman, a professor in the Department of Earth & Environment at Florida International University in Miami and researcher into rip currents, who told Al.com, “I think everyone should stay out of the water, go to the pool or watch (the Gulf) from ashore. When the storms are far away, and people think, ‘What’s the problem?’ that is the formula for a disaster.”

Swimmers caught in a rip current, the weather service says, should stay calm, call for help, and float rather than struggle against the flow.

The high risk of rip currents on Alabama beaches is expected to last through Sunday night, then drop to moderate Monday before returning to high Tuesday and Wednesday, according to the weather service.

A coastal flood advisory also remains in effect from Destin, Fla., west through Alabama until 1 a.m. Sunday.

As of Saturday afternoon, Beryl was 415 miles southeast of Corpus Christi, Texas, moving west-northwest at 12 mph. The storm, which has already caused extensive damage in Mexico and parts of the Caribbean, had maximum sustained winds of 60 mph. It was expected to gain strength Saturday and Sunday, and hurricane warnings are likely for parts of the Texas coast this weekend.