September 2017
Hurricane Irma generated about $25bn in insured losses, including $18bn in the US and $7bn in the Caribbean, Karen Clark & Company estimated today.
Included in the totals are losses to buildings and insured structures, contents, autos and business interruption, the company said.
The assessment excludes losses covered by crop insurers and the National Flood Insurance Program run by the Federal Emergency Management Agency, the catastrophe modelling firm said.
As one of the most powerful Atlantic hurricanes on record, Irma posed a much greater threat before being pushed west as it headed toward the US.
Had the track not made that shift before making landfall on the continental US and hit Miami, the insured losses might have been as much as $150bn, the company said, mainly driven by strong winds.
As it was, the storm’s track brought it ashore on the Gulf of Mexico side of the Florida peninsula, about 50 miles south of Fort Myers and took it inland.
Irma’s intensity weakened as it passed east of the Tampa-St Petersburg area.
The track spared both Miami and Tampa-St Pete from the worst of Irma’s wrath as even the Gulf storm surge brought on by the hurricane proved lower than anticipated. The cities on the central Gulf coast are among the most at risk from surge in the Sunshine State, the modeller said.
“Even the wind damage turned out to be relatively minor” after the storm’s rapid decay, the company said. “Direct wind impacts were mostly limited to mobile homes, light structures, signage, and spotty roof and window damage” in the parts of the Florida mainland that Irma passed over.
The modeller said most of the insured loss in the US occurred in Florida. In addition, losses occurred in parts of Georgia, South Carolina and Alabama, where Irma brought heavy rains.
But the storm’s strong winds in its northeast quadrant extended out over the Atlantic as well and led to higher than expected storm surge and flooding in cities such as Jacksonville, Florida and Charleston, South Carolina. Even in parts of downtown Miami surge driven flooding occurred.
In the Caribbean, Irma swept across islands with full destructive force brought against St Martin, Barbuda, Anguilla and the British Virgin Islands. Over 50 percent of property value was destroyed on the hardest hit islands, the company said.
While the storm spared much of Puerto Rico, the Florida Keys, especially east of Cudjoe Key where Irma made its first US landfall, were raked by 130mph winds and flooding. Irma’s greatest destruction in the US took place in the Keys.
The storm, which had sustained winds of as much as 185mph (1,270 kph) as it churned across the Caribbean, was one of the strongest Atlantic hurricanes on record and the most powerful ever to strike the Leeward Islands, the company said. It was the strongest storm to hit the Bahamas since Hurricane Andrew in 1992.
