A 'falling iguana' warning has been issued for parts of southern Florida this week

Some Florida residents may end up with a surprise Christmas gift this year — an iguana to the head.

That's because the National Weather Service has warned locals that if it gets too cold, iguanas may start falling out of the trees.

They're usually not dead, animal experts cautioned, but because iguanas are cold-blooded, their bodies begin to protectively shut down when the temperature plunges. As their joints stiffen up, their tiny iguana arms can lose the ability to grip tree branches and they may fall to the ground.

Experts advise that if you see one you should leave it alone; they've been known to bite people as they thaw out of their dormant state.

"Even if they look dead as a doornail — they're gray and stiff — as soon as it starts to heat up and they get hit by the sun rays, it's this rejuvenation," Ron Magill, communications director of the Miami Zoo told The New York Times in 2017. "The ones that survive that cold streak are basically passing on that gene."

This is not the first falling iguana warning the weather service has had to issue. They're given fairly regularly, including this January when temperatures in the state dipped into the 30s and 40s.

The falling iguanas can sometimes be disastrous. In 2017, Davie, Florida, photographer Dan Palma was shocked when an iguana fell out of the sky and smashed his van's windshield in. The force of the blow actually woke the iguana out of his dormant state, and Palma told Local 10 News the lizard hung around on the roof of his car for a while.

Temperatures in southern Florida on Friday are expected to potentially drop below 40 degrees Fahrenheit, according to the National Weather Service's Miami bureau.

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