Potentially life-threatening cold spread across the Deep South on Saturday, as forecasters issued winter weather advisories in multiple states and warned that freezing temperatures would likely last for the next several days.

The advisories covered eastern Louisiana and most of Mississippi and Alabama.

Freezing rain and a wintry mix was possible through the weekend, the National Weather Service said. Then, low temperatures could drop below 15 degrees in parts of Louisiana and Mississippi during the first few days of 2018, forecasters said.

In Georgia, advocates for the homeless feared the unusually long stretch of frigid weather in Atlanta could kill some homeless people in the city. The temperature in Atlanta is expected to dip into the low 20s on New Year's Eve, and plunge into the teens Monday and Tuesday night.

"A lot of people are ready for the night but occasionally we bump into people who are totally unprepared," said Drew Benton, who works with volunteers who go beneath bridges and other areas where Atlanta's homeless spend the night. They give them clothing, blankets and other items on the coldest nights of the year.

"We've seen people in a T-shirt and jeans walking around. We've seen children out there before - we've seen a lot of circumstances where people are just totally unprepared," Benton said.

Benton's nonprofit, Project Live Love, blasts an email to volunteers announcing a "go night" whenever the temperature is expected to fall below 31 degrees. He said they're prepared to hit the streets and distribute supplies for the next eight nights if the freezing temperatures continue as expected.

One item they hand out is dry socks, which can be a life-saver.

"A lot of our freezes will come with a rain before it and if you get your feet wet, you're in a lot of trouble," he said.

The start of the new year will also mark the coldest temperatures in Atlanta since its largest shelter, known as Peachtree-Pine, closed. People who work with the homeless believe that the closure this fall has now exposed more homeless people to the elements.

When Benton's teams distributed supplies on Dec. 8, "the streets were just covered with people," he said. Under one bridge downtown, they saw about 150 people trying to stay warm.