On Thursday morning, Frank Cerabino, a columnist for the Palm Beach Post, woke up to 40-degree weather and was greeted by a "frozen iguana" lounging by his pool in Boca Raton, Fla.

He responded as many people probably would: He shared a photo on social media. Then he pondered, "What do you do?," he told the New York Times.

One of the strongest winter storms on the East Coast in modern history has pummeled cities with snow and sleet, forcing schools and businesses to close while grounding thousands of flights.

And in South Florida, it is raining iguanas.

Green iguanas, like all reptiles, are coldblooded animals, so when the temperature falls to a certain level, they become immobile, said Kristen Sommers of the Florida Fish and Wildlife Conservation Commission. Under 50 degrees Fahrenheit, they become sluggish. Under 40 degrees, their blood stops moving as much, Sommers said.

They like to sit in trees, and "it's become cold enough that they fall out."

This is not a new phenomenon – there were similar reports in 2008 and 2010 – though it is not typical.

"The reality is South Florida doesn't get that cold very often or long enough that you see this frequently," Sommers said.

But what should one do with a fallen iguana?

Cerabino told the New York Times that he prodded the iguana with a pool skimmer.

"He didn't move," Cerabino said. "But he's probably still alive. My experience is that they take a while to die."

Maxine Bentzel, a reporter at CBS12 News, suggested that "iguanas have a good chance of thawing out if you move them into the sun."

The experts would prefer you didn't.

Sommers said the reptiles could become frightened as they warm. "Like any wild animal, it will try to defend itself," she said.

And there are cautionary tales.

Ron Magill of the Miami Zoo told WPLG TV in 2010 about a man who collected sleeping iguanas and threw them into the back of his station wagon. Then they awoke. "All of a sudden these things are coming alive, crawling on his back, and almost caused a wreck."

The winter storm sweeping across parts of the East Coast has prompted animal-rescue organizations and local authorities to issue warnings about giving pets shelter, with dogs left out to freeze to death in the cold.

In South Florida, the cooler temperatures also affect sea turtles, manatees, and other creatures.

"Bats sometimes will fall out of the roost of trees when we have a pretty cold snap," Sommers said.

Sommers said that while she's heard of falling iguanas on social media, the agency hasn't gotten any reports of falling iguanas.

"There have not been an influx of calls to FWC about people worried about iguanas falling out of trees," she said. "It's not like something you see every year."