Updraft® - Minnesota Weather News

Forecast models lock in on Ian's devastating blow to Florida.

Multi-billion dollar weather disaster likely. Damaging storm surge, winds, and up to 2 feet of rainfall with freshwater flooding.

GOES-16 visible loop of Hurricane Ian
GOES-16 visible loop of Hurricane Ian Tuesday.
NOAA via COD Weather Lab

Hurricane Ian continues to churn steadily toward Florida’s Gulf Coast Tuesday. And the scope of the next likely human and multi-billion dollar weather and climate disaster is becoming clearer.

There is still some uncertainty on the specific forecast track, storm surge, and rainfall flood scenarios to unfold. But the reality of a major hurricane hitting one of the most heavily populated coastlines with multiple billions to trillions in real estate is near certain now.

Ian will extract a devastating human toll for Floridians. And Ian is almost certain to be the next multi-billion dollar weather disaster.

Offical forecast

Let’s start with the best official information for Hurricane Ian. Tuesday afternoon’s National Hurricane Center’s forecast track and intensity for Ian project a major hurricane to make landfall on Florida’s Gulf Coast somewhere between Tampa and Fort Myers Wednesday evening.

Hurricane Ian
Hurricane Ian track forecast.
NOAA/NHC

That forecast has evolved both faster and further right (south) since Monday evening.

Ian’s maximum sustained winds are forecast to reach 130 mph Wednesday before landfall. That’s a high-end category 4 storm.

Forecast models: Mix of bad outcomes

The major forecast models all bring slightly different but equally damaging outcomes to Florida’s Gulf Coast. It’s really just a question of which areas get the biggest storm surge, highest winds, and heaviest rainfall that will cause (massive?) freshwater flooding.

The European model is just one that suggests a near worst-case scenario along the Gulf Coast between Fort Myers and Tampa. Tuesday’s latest 12Z Euro forecast run brings a major hurricane very close to Fort Myers/Cape Coral then moves it up the coast and inland to just east of Tampa.

The Euro then takes the system through the Orlando area to Florida’s east coast. This would cause widespread damage in many sections of central Florida from the Gulf to the Atlantic costs.

European model (ECMWF) output
European model (ECMWF) output between 7 pm Tuesday and 1 pm Friday.
ECMWF via tropical tidbits

Feet of rain? Massive freshwater flood potential

Several forecast models paint a swath of multi-FOOT rainfall across parts of Florida’s Gulf Coast. Two to more than three feet of rain would cause devastating freshwater flooding.

Some forecast models suggest Ian will slow down near and after landfall. That could produce Hurricane Harvey flood levels. Harvey dumped 25 to more than 50 inches of rainfall around the Houston area.

Tampa to Fort Myers: Massive damage potential

Ofiicial NHC forecast tracks brings Ian ashore somewhere between Tampa and Fort Myers Wednesday night. That’s the most densely populated section of Florida’s Gulf Coast with more than 5 million people. The area includes Tampa, St. Petersburg, Bradenton, Sarasota, Port Charlotte, Cape Coral, and Fort Myers.

Florida Gulf Coast
Florida Gulf Coast cities.
NASA images via Google

In addition to the human toll, more than a million homes and hundreds of billions of dollars of low-lying real estate sit on or near the coast, and along rivers and canals that cut well inland. Those openings provide a direct path for storm surge floodwaters to inundate neighborhoods.

Core Logic damage estimates from Monday’s forecast are staggering.

1,044,412 single-family and multifamily homes along the Florida Gulf Coast with a reconstruction cost value (RCV) of approximately $258.3 billion are at potential risk of storm surge damage from Hurricane Ian. These figures assume Hurricane Ian makes landfall as a Category 4 hurricane and are based on the Sept. 26, 2022 National Hurricane Center 11 a.m. E.T. forecast.

Again, the human factor is the most important. But part of that is the likely damage to people’s homes, businesses, and local economies that Ian will bring.

It is estimated that 2017’s Hurricane Harvey alone had total costs of $125 billion—second only to Hurricane Katrina in the period of record, which had an approximate cost of $161 billion.

If current forecasts for Ian verify, we could be looking at hurricane damage losses in at least the 10s to hundreds of billions of dollars.

All signs indicate we may be about to witness one of the worst weather disasters in U.S. history unfold in the next 72 hours.