Another death. Three more rescued. What's going on?

As the search for a missing swimmer resumed Friday, a second woman's body washed ashore on Folly Beach, and three other swimmers were rescued from Sullivan's Island.

While officials investigated the causes of the beach incidents, they reminded people that powerful rip currents near inlets in the Lowcountry have long been a dangerous situation for swimmers, especially as the tide is receding.

Sullivan's Island Fire Chief Anthony Stith advised beach-goers not to go farther than knee-deep in the water while the currents and wind are strong. There are no life guards on the beach.

"Right now, I don't think it's safe to go out in the ocean," Stith said. "You've got to be aware of what's going on out there."

About 6:05 a.m., walkers discovered the body of 39-year-old Tara Lynn McAllister in the surf line on Folly Beach across from the Morris Island Lighthouse. Responders pulled her to shore and established a crime scene, Folly Beach Public Safety Deputy

Chief Brad Wade said.

Charleston County Chief Deputy Coroner Judy Koelpin said McAllister's vehicle was found parked on Sullivan's Island, and she probably drowned. Koelpin would not say whether there was any trauma to the body. Neither the deputy coroner nor police officials from either beach would say whether foul play is suspected. The Charleston County Sheriff's Office and Folly Beach and Isle of Palms police are investigating.

McAllister, 39, of Goose Creek, was a social worker at the Ralph H. Johnson VA Medical Center and a former victim's advocate for the Goose Creek Police Department.

Her neighbors said about 15 law enforcement vehicles were at her home on Friday.

Neighbor Terry Mouser described McAllister as a quiet, single woman who lived alone with her two dogs. He said McAllister bought her first home in the Crowfield Plantation community in 2007 and spent much of her time renovating the house.

"It's awful," Mouser said of the death. "She was a beautiful person."

Stuhr's Downtown Chapel in Charleston is handling the arrangements.

Missing swimmer

Anna Finkelstein, of New York City, went swimming with Rebecca Fanning of West Ashley about 3:45 p.m. Thursday near Station 28 on Sullivan's Island below Breach Inlet. The women, in their early 20s, set out for a sandbar as the tide was quickly receding, but they never made it.

They were swept outward and south toward Charleston Harbor. Finkelstein said she couldn't swim any longer, and Fanning tried to go ashore for help but had to be rescued. An Atlanta man visiting the beach pulled her out of the water, but Finkelstein was never seen again.

Local rescue workers searched the waters by boat and helicopter until dark and resumed at first light Friday morning. The U.S. Coast Guard, S.C. Department of Natural Resources, Charleston County Sheriff's Office and the Sullivan's Island and Isle of Palms fire departments expanded the grid-based search to Folly Beach and farther east into the Atlantic.

They didn't find Finkelstein, but they rescued three men in an unrelated incident near Station 18.

Another rescue

The Sullivan's Island Fire Department received a call around 1:25 p.m. saying the men were struggling in the water about 100 yards from shore. One of the search boats happened to be nearby, and rescuers plucked them out of the ocean.

Fire Chief Anthony Stith said the men, ranging in age from their 20s to 40s, might not have all survived had the vessel not already been there.

"We might've been able to save a couple of them, but I don't think we would've been able to save all three of them," Stith said.

The men were taken to East Cooper Regional Medical Center and were in stable condition, Charleston County EMS Director Don Lundy said. Stith said one had swallowed a good deal of water.

Michael Moore, 38, of Mount Pleasant, was rescued from a near drowning at Sullivan's Island on June 22 and was taken to the East Cooper hospital, where he died June 28, Charleston County Coroner Rae Wooten said.

The search for Finkelstein has been called off.

Dangerous currents

The threat of rip currents will be low along the beaches today, the National Weather Service forecasts.

Weather will be sunny with the high temperature in the mid-80s and predominantly onshore winds, which don't tend to exacerbate rip currents, said meteorologist Joe Calderone, of the weather service's Charleston office. Other factors that spur rip currents — higher than normal tides and long swells along the coast — aren't there.

Rip currents are narrow, rushing runs that tend to form in the breaks between the sandbars offshore; they are caused by retreating waves. Around inlets, where the two women apparently died this week, powerful tidal currents occur when low tides force water to jet through narrow channels along sand shoals.

"Around Charleston and throughout the Lowcountry, currents are very strong on the north and south end of islands as a result of strong flows and the prevalence of adjacent shoals that focus the currents," said Clay McCoy, coastal processes specialist with South Carolina Sea Grant Consortium and Coastal Carolina University.

"Most rip-current drownings or rescues come around low tide. In this area, as tide falls, bare shoals are exposed in Breach Inlet and in front of Sullivan's Island. This forces water coming out of the Intracoastal Waterway and tidal creeks to focus in the channels located between the shoals and causes very strong currents. There's just a whole lot of current moving in a very fast river."

Bo Petersen, Paul Bowers and Andy Paras contributed to this story.