Hurricane Ian sucked water away from Florida's coast as it moved north

Hurricane Ian delivered an eerie omen to coastal Florida residents Wednesday morning, as the powerful storm's winds pulled massive amounts of water away from beaches and shorelines, exposing the seabed that's normally covered by feet of ocean water.

Spectators and photographers gaped at the suddenly remade coastlines — but the water is expected to return with a vengeance: The latest storm surge estimates predict up to 12-18 feet of water above ground level hitting an area from Englewood south to Bonita Beach, the National Hurricane Center said.

"IMPORTANT NOTE: The water WILL come back," the National Weather Service office in Tampa said via Twitter, as it urged people not to walk out to explore areas where water has receded.

When it does arrive, the high water "will likely be accompanied by large and destructive waves," the NHC said.

The city of Venice, Fla., posted images from the fishing pier, showing the water swept out nearly to the structure's edge.

Why does this happen?

It's physics playing out on a large scale. Hurricane Ian's winds are swirling counter-clockwise as it moves northward along the Florida peninsula, so its winds are whipping the water away from the shoreline ahead of the center. As the storm passes through, winds in its eastern and lower half will shove water back toward land — and inland — at a prodigious rate.

It's happened before, but rarely to this degree. Hurricane Irma caused a similar phenomenon in 2017.

"Storm surge is where strong winds are pushing the water towards the shore. But you can imagine that same force is pushing water away from the shoreline," the NHC's Jamie Rhome said in 2017. "If the wind is blowing offshore, it blows water away from land."

Water is the biggest threat to life in hurricanes

Ian's sustained winds of up to 155 mph are drawing fear and dread, and they're expected to cause catastrophic damage. But experts have repeatedly warned that the storm surge and floodwaters pose a dire threat.

Historically, "water accounts for about 90% of the direct deaths" from U.S. hurricanes, according to the National Hurricane Center.

Ian's storm surge will arrive after its outer bands have already soaked the ground. In the past 24 hours already, Fort Myers reported more than 3 inches of rain. There's much more to come: Ian is predicted to slow down as it nears the shore, increasing rain levels on the coast and far inland.

And while storm surges were for decades the main culprit, in recent years inland flooding has been responsible for most water-related deaths — including a high number of incidents that involved people in vehicles.

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