Deep Freeze and Drought Fueled a Massive Florida Wildfire

Firefighters in southwest Florida on Friday continued battling an expansive blaze on a federal nature preserve as an unusually intense winter drought grips the state.

The National Fire has burned more than 25,700 acres — an area larger than Manhattan — since Sunday in the Big Cypress National Preserve south of Naples. The region is a popular tourist destination known as “Alligator Alley” for its plentiful wildlife.

Fire risk in the preserve has ramped up since a historic deep freeze hit Florida in late January, which brought rare snow and left citrus groves tinged with damaging frost. Temperatures in the state plunged low enough to kill off small plants and grasses that are now tinder-dry and rapidly burning, said Michelle Lewis, a public information officer for the preserve. Winds picked up early in the week, fanning the blaze.

“What is abnormal is the combination of all those things,” Lewis said. “That’s made this a bit more challenging.”

Though the fire is technically uncontained — meaning it’s still smoldering around its edges — Lewis said crews have intentionally expanded the blaze through “defensive” burning, to prevent the fire from suddenly jumpingacross nearby roadways.

Still, heavy clouds of dark smoke have drifted across Interstate 75, which connects Naples to Fort Lauderdale. The freeway was closed on Wednesday due to low visibility. On Thursday, officials reopened the road.

The cause of the fire is still under investigation as of Thursday, Lewis said, adding that officials had previously suspended all prescribedburns in the 729,000-acre preserve due to dangerously dry conditions. Beyond swamps, Big Cypress includes prairies and pinelands that are naturally prone to fire. The preserve typically sees thousands of acres of controlled burns per year, Lewis said, to mimic natural fire cycles and keep the pinelands healthy.

The National Park Service is responsible for managing the preserve, which sits at the western edge of the Everglades ecosystem. Big Cypress also surrounds the so-called “Alligator Alcatraz” immigration detention facility, a controversial project built at a small airport roughly 30 miles (48 kilometers) east of the fire.

Southern Florida’s notorious swamps tend to shrink in winter, which is traditionally the region’s dry season, said Ana Torres-Vazquez, a meteorologist for the US National Weather Service in Miami.

The Southeast is no stranger to fire: The region typically sees more than a week’s worth of risky fire conditions each year, according to statistics compiled by nonprofit Climate Central, which have ticked up slightly in recent decades. In an average year, Florida endures more days of “red flag” fire weather warnings than California and other western states.

This winter has been intensely dry as La Niña steers rain away from the Southeast. The entire state of Floridahas been starved for moisture in recent weeks, according to the US Drought Monitor. Extreme drought conditions have now spread across much of the state’ssouthern tip.

A storm front approaching the fire zone this weekend could bring scattered showers, Torres-Vazquez said, but rainfall is expected to top out around an inch (2.5 centimeters).

“It does not look like a lot of rain that could really help conditions,” she added.