CoreLogic® estimates storm surge could affect 808,321 homes in Florida
Hurricane Idalia is expected to be the first major hurricane of the 2023 season to make landfall in the U.S. Although the first major hurricane to make landfall, Idalia is not the only hurricane to hit the U.S. this season. Earlier this month, Hurricane Hilary made landfall in Baja California, Mexico, as a Category 1 storm prior to soaking the southwestern U.S.
As a major Florida storm, Idalia is expected to bring hurricane-force winds, catastrophic storm surge and widespread inland flooding across Florida and the southeastern U.S.
CoreLogic® estimates approximately 808,321 single- and multifamily residential properties with $238.4 billion in combined reconstruction cost value (RCV) are at risk of storm surge flooding along the west coast of Florida. The largest number of at-risk homes are located in three Florida counties: Lee County, Pinellas County and Sarasota County.
|County Name||Count||RCV ($ bn)|
|All Other Counties||25,628||7.1|
Table 1: Residential property and total reconstruction cost value ($ Billions) Total reconstruction cost value of single- and multifamily residential properties at risk of storm from Hurricane Idalia
Note, not all properties listed above will sustain damage. The number of damaged properties will be a subset of the total 808,321 buildings. A damaged structure may not sustain 100% loss up to the full RCV. The RCV figures presented above represent the cost of completely rebuilding the existing residential structure. The RCV amount includes the costs of materials, equipment and labor, but it does not include the value of the land or lot.
The single-family residential category includes structures with fewer than four stories, including mobile homes, duplexes, manufactured homes and cabins (among other non-traditional home types). Multifamily structures include apartments, condominiums and multi-unit dwellings. Other land use types such as non-residential commercial, industrial and agriculture are not included.
About Idalia: The Tropical Storm Turned Category 1 Hurricane
On Monday, Aug. 29 at 5:00 a.m. local time (9:00 a.m. UTC), Idalia was in the southeastern Gulf of Mexico, 85 miles (135 km) off the tip of western Cuba and 370 miles (600 km) south-southwest of Tampa Bay, Florida, according to the National Hurricane Center (NHC) Advisory #11. Current maximum sustained wind speeds are 75 mph (120 km/h), making Idalia a Category 1 hurricane.
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The NHC forecasts Hurricane Idalia to rapidly intensify and accelerate north then north-northeast before making landfall in the Big Bend coastal area of Florida. The NHC expects Idalia will reach major hurricane status (Category 3 or greater) with maximum sustained wind speeds of 120 mph (194 km/h) prior to landfall.
Landfall is expected to be somewhere between Franklin County, Florida, and the Tampa Bay – St. Petersburg area (Figure 1). A hurricane warning extends from Franklin County to Tampa Bay. Tropical storm warnings extend south to Naples, Florida. Tropical storm warnings are also in place on the east coast of Florida.
The NHC forecasts Idalia to weaken to a tropical storm after landfall.
Life- and property-threatening coastal flooding from storm surge along the west coast of Florida is possible. Storm systems that make landfall along the Gulf Coast are likely to generate a more substantial storm surge than equivalent storms that hit the Atlantic Coast. This fact combined with Idalia’s angle of approach relative to the Florida coastline makes the threat of a devastating surge possible.
The NHC forecasts surge depths of 8 to 12 feet above ground surface from the Aucilla River in the Apalachee Bay to the Chassahowitzka River in Florida’s Citrus County. Storm surge depths of 4 to 7 feet above ground surface are possible in Tampa Bay – St. Petersburg area (Figure 2).
The National Weather Service expects extensive and intense rainfall across northern Florida as well as coastal George and the Carolinas. A moderate (at least 40% chance) flash flood risk is possible through Friday, Sept. 1, especially in urban environments such as Jacksonville, Florida; Savannah, Georgia; Charleston, South Carolina; and Wilmington, North Carolina (Figure 3). A slight flash flood risk (at least 15% chance) extends as far inland as Chattanooga, Tennessee and Atlanta.
CoreLogic Hazard HQ Command Central™ will continue to watch Hurricane Idalia. Updates may be provided when is more known.
CONTACT: Please email HazardRisk@corelogic.com with questions regarding Hurricane Idalia or any CoreLogic event response notifications.
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