Forecasters say Ian is poised to spend days dumping rain on Florida after it makes landfall as a hurricane, a troubling scenario that could lead to widespread flooding and damage.
The storm is forecast to slow to a crawl as it reaches land, leading to extended rainfall up to 2 feet in some areas that may see localized flooding.
A Tuesday National Hurricane Center forecast shows the storm could slowly trek through the state from Wednesday through Friday.
Ian is likely to impact the entire state, with the areas in its direct path expected to see widespread damage and winds of well over 100 mph, according to Anthony Reyes, with the National Weather Service in Miami. Plus, coastal areas along the Gulf of Mexico are even more prone to storm surge floods.
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Here's what to know about how Hurricane Ian's winds and flooding will impact Florida:
How much rain is Florida going to get?
Parts of Central Florida could see 12-16 inches of rain with 2 feet possible in isolated areas, according to the National Hurricane Center. Other areas of the state might see between 6 and 8 inches, with isolated areas getting up to a foot.
Some areas on the western coast of the state, such as Charlotte Harbor, should expect to see 8-12 feet of storm surge, the center said.
"In some areas there will be catastrophic flooding and life-threatening storm surge," Gov. Ron DeSantis said Tuesday.
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What makes Ian dangerous?
Ian is expected to make landfall in Florida, somewhere between Tampa and Fort Myers, and then continue moving through Central Florida as it weakens. It will already be moving as slowly as 5 mph when it hits, which means its path through the state will be slow.
"When these kind of systems slow down, they allow for an even more extended period of time for the same locations to receive rains," Reyes said. "That exacerbates the potential for localized flooding."
Reyes said the concentrated metro areas in the storm's path are especially at risk. Flash and urban flooding are expected mid-to-late week across central and northern Florida, southern Georgia and coastal South Carolina.
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Ponds could help curtail flooding impacts
Florida's flood management system includes tens of thousands of stormwater ponds, which are built in developed areas to help collect and store stormwater runoff.
In residential and commercial areas where stormwater ponds are common, a "buffer" may help curtail flooding impacts, said Eban Bean, an assistant professor in the University of Florida's Department of Agricultural and Biological Engineering.
"While they're not going to be able to catch all of this stormwater volume, they are going to help by slowly releasing that water downstream rather than letting it all come at once whenever the rain is at its most intense," Bean said.
Even still, the stormwater ponds just aren't built to handle the amount of rainwater expected with Ian, and excess volume will likely cause flooding that persists while the mitigation systems drain it out. But neighborhoods in Ian's path with stormwater ponds, such as Lakewood Ranch which has over 300, may fare better than those without.
How long will it take to recover?
In some areas of the state, structural damage caused by hurricane-level winds could make some residential buildings "uninhabitable" for weeks or even months, the National Weather Service in Miami said.
As for flooding, water could take several days to fully drain because of Florida's relatively flat topography, Bean said. And recovery also depends on subsequent weather activity, Bean said; if other tropical systems form, it could take much longer.
"This is going to be a test of our (stormwater management) system," Bean said.
This article originally appeared on USA TODAY: Hurricane Ian: Florida faces days of rain, flooding if storm slows