The National Weather Service in Miami is calling for "falling iguanas" in its holiday forecast.
Temperatures in South Florida are expected to drop into the 30- to 40-degree range on Christmas Day and into the weekend, creating conditions that may cause iguanas to suddenly drop out of trees, the NWS said on Twitter.
Dec 21 - Brrr! Much colder temps expected for Christmas. Low temperatures in the 30s/40s and falling Iguanas are possible. Keep up with forecast changes and stay warm! #flwx pic.twitter.com/BRYfugIE5Q— NWS Miami (@NWSMiami) December 21, 2020
Iguanas can't handle cold weather because they are cold blooded, so when the temperature drops below about 45 degrees their bodies go dormant. They appear to be dead, but they are not. They remain breathing with critical body functions still operating.
This phenomenon, mixed with the species' tendency to sleep in trees, can create quite the surprise for someone in a car or walking under a tree, and since some iguanas are large -- adult males can reach 5 feet in length, and weigh up to 20 pounds -- this can be dangerous to passersby.
The danger for the iguana comes when temperatures remain in the 40s for periods over eight hours. The invasive species is then at risk of death, especially the smaller ones.
"The temperature threshold for when iguanas begin to go into a dormant state depends greatly on the size of the iguana," Ron Magill, communications director for Zoo Miami told CNN when the temperatures dropped in January. "Generally speaking, the larger the iguana, the more cold it can tolerate for longer periods."
He also commented that many iguanas in South Florida have adapted to digging deep burrows, so they are insulated from the cold. Iguanas also tend to live close to large bodies of water, which can be warmer than the air temperatures, so it can help them survive short cold snaps.
RELATED: Best Christmas movies of all time, according to critics
Best Christmas movies of all time, according to critics
#26. Trading Places (1983)
#25. Happy Christmas (2014)
#24. Bad Santa (2003)
#23. Gremlins (1984)
#21. Rare Exports: A Christmas Tale (2010)
#20. Kiss Kiss Bang Bang (2005)
#19. Die Hard (1988)
#18. Tokyo Godfathers (2003)
#17. Edward Scissorhands (1990)
#16. Metropolitan (1990)
#15. A Christmas Story (1983)
#14. 2046 (2004)
#13. Christmas, Again (2014)
#12. Tuesday, After Christmas (2010)
#11. C.R.A.Z.Y. (2005)
#10. Eastern Promises (2007)
#9. The Nightmare Before Christmas (1993)
#8. A Christmas Tale (2008)
#6. Little Women (1994)
#5. Miracle on 34th Street (1947)
#4. It's a Wonderful Life (1946)
#3. Little Women (2019)
#2. The Apartment (1960)
#1. Carol (2015)
#7. Tangerine (2015)
CNN's Allison Chinchar contributed to this report.