The US Gulf Coast can’t get a break from this year’s hurricane season. Hurricane Delta is forecast to make landfall this Friday, less than one month after Hurricane Sally’s landfall.
In August, Hurricane Laura made landfall as the strongest hurricane on record to make landfall in Louisiana. In June, Tropical Storm Cristobal brought widespread flooding and storm surge to Louisiana, Alabama, and the Florida Panhandle.
What is driving this year’s extreme tropical activity?
La Nina is a contributing factor to this year’s increased tropical activity. “La Nina can contribute to an increase in Atlantic hurricane activity by weakening the wind shear over the Caribbean Sea and tropical Atlantic Basin, which enables storms to develop and intensify,” said Mike Halpert, deputy director of NOAA’s Climate Prediction Center. “The potential for La Nina development was factored into our updated Atlantic hurricane season outlook issued in August.”
Unusually warm sea surface temperatures (SSTs) are also a key factor. Most of the tropical and subtropical Atlantic, including the Gulf of Mexico, has run warmer than average this hurricane season.
Risk management executives can’t help but wonder if this level of tropical activity is the sign of a ‘new normal’. One thing is for sure, the last 20 years of storm-related claims activity looks a lot different than the last 60 years.