Hurricane Milton insured losses are estimated at $US30-$US50 billion ($44-$74 billion), with the ultimate cost depending on repair supply constraints as the US southeast also recovers from Helene’s impact two weeks earlier, Fitch Ratings says.

The Milton estimate would be the largest loss since Hurricane Ian cost $US60 billion ($89 billion) in 2022 after crossing the coastline at category 4 strength and ravaging a similar area.

“The insurance losses will hit reinsurance attachment points, shifting a meaningful amount of losses to the reinsurance market, particularly from the Florida specialist companies with lower retentions,” Fitch Ratings says.

Hurricane Milton crossed Florida’s west coast south of Tampa at category 3 intensity about 8.30pm last Wednesday (local time), bringing storm surges, damaging winds, flooding and tornadoes.

It remained at hurricane strength as it crossed the peninsula before moving back over the ocean.

Fitch says Milton is unlikely to affect credit for rated property and casualty insurers and global reinsurers given their capital levels, but Florida specialists, which the agency does not rate, are vulnerable to the extent the hurricane generates losses above reinsurance limits.

Moody’s RMS Event Response says extreme rainfall led to record-breaking pluvial and fluvial floods. 

Media reported the Hillsborough River at Zephyrhills in Florida surged from about 1.2 metres to more than 5.2 metres within 24 hours, and 3.3 million customers lost power across the state.

Moody’s RMS says the event underscores the region’s flood insurance protection gap. Despite Florida having the highest number of National Flood Insurance Program policies in the US, take-up rates fall to low single digits in inland areas. 

Hurricane Milton had reached category 5 intensity, fuelled by record and near-record warmth across the Gulf of Mexico, but it eased shortly before reaching the coast.

A fortnight earlier, Hurricane Helene made landfall in Florida’s Big Bend region at category 4 strength but caused its worst damage as it swept inland through southeast states including North Carolina.

Moody’s RMS Event Response last week estimated private market insured losses from Helene at $US8-$US14 billion ($11.9-$20.8 billion), with a “best estimate” of $US11 billion ($16.4 billion).