Why the Gulf is getting hammered in this record hurricane season but the East Coast has been spared
Although the season as been historically active, it's unlikely to rival past seasons for disaster costs and damages.
When Hurricane Delta smashed ashore along the Louisiana coast at 6 p.m. Friday it became the 10th tropical storm to make landfall in the United States in 2020, breaking a record that had survived more than a century.
It was the seventh storm to land on the Gulf shores, which have been a tropical-storm punching bag in this ultra-busy and peculiar season. It also was the second significant hurricane in six weeks to target the same region of southwestern Louisiana. Its predecessor, Hurricane Laura, was blamed for 14 deaths.
By comparison, the Atlantic Coast has been showered with luck. And in a historically active hurricane season, so have U.S. taxpayers.
Taken together, the collective U.S. damage caused by all 25 storms this season likely won’t come close to matching those of individual catastrophic storms that caused massive destruction in highly populated areas such as Katrina, in 2005, and Sandy, in 2012.
Only one 2020 hurricane, Isiais, has made landfall on the Eastern seaboard, and that was only a Category 1, with top winds of 85 mph when it reached the southern coast of North Carolina.
The Philadelphia region suffered some serious whiplash from Isiais' remnants and from Fay’s. It may see generous rains — possibly 1 to 3 inches — from Delta’s leftovers late Sunday into early Tuesday, but those, too, would qualify as good fortune. So far this month Philadelphia has had a grand total of 0.12 inches.
Right about now, residents along the southwestern Louisiana coast could use something more than good fortune.
Why all the Gulf storms?
Hurricanes have a tendency to pick on a given region in given seasons. In the late 1990s, North Carolina was a favored target. This year, it has been the Gulf region.
One factor has been the generally quite-warm Gulf water temperatures, which have been supplying the storm fuel, said Dan Kottlowski, hurricane specialist with AccuWeather Inc.
But the big drivers have been persistent steering winds in the upper atmosphere. Storms have been riding the circulation around high pressure centered in the North Atlantic.
Winds blow clockwise around centers of high pressure, thus east-to-west on their southern flanks. “It just so happens that this high has been nosing westward this year,” Kottlowski added, directing storms into the Gulf.
In terms of areal coverage, as ferocious as they appear in satellite images, hurricanes actually are small, relative to winter storms that can have peak effects over several hundred miles.
Location, location, location
Because maximum storm-surge and wind impacts of hurricanes are relatively confined, where they come ashore can make all the difference in fatalities, damage, and overall impact.
Andrew, in 1992, made landfall just south of Miami with peak winds of 170 mph and became one of the costliest storms on record, causing $87 billion in “normalized” damage, based on inflation rates and today’s level of building, according to ICAT, the catastrophe-insurance firm.
The Great Miami Hurricane of 1926 made a direct hit on the city, and if that same storm struck today, the normalized damage would be triple Andrew’s.
Katrina devastated New Orleans, killed more than 1,800, and ranks No. 3 on the ICAT scale at close to $150 billion in damage.
Laura, which hit the less populated western Louisiana coast six weeks ago, likely will end up with an $8 billion to $12 billion price tag, said Phil Klotzbach, hurricane researcher at Colorado State University.
A whole lot of hurricane damage costs are related to government expenditures, and they have been rising dramatically thanks to the decades-long floodplain building booms and rising water levels related to worldwide warming.
In his deeply reported book The Geography of Risk: Epic Storms, Rising Seas, and the Cost of America’s Coasts, former Inquirer reporter Gilbert M. Gaul noted last year that roughly 70% of FEMA’s hurricane disaster aid payouts since 1950 had been made in the prior 10 years.
Meanwhile, the federally backed National Flood Insurance Program, for which the U.S. Treasury is the backstop for losses, remains swamped in debt thanks largely to hurricane-related flooding.
As of Sept. 30, the debt stood at $20.5 billion, even though three years ago Congress “canceled” $16 billion of the program’s indebtedness — meaning the taxpayers picked up the tab.
This season, which ends Nov. 30. is making a run at the 2005 record of 28 named storms, but a lot of this year’s have been “one day wonders,” said Frank D. Marks, director of the Hurricane Research Division at NOAA’s Atlantic Oceanographic and Meteorological Laboratory.
And barring a horrific late-season hurricane that targets highly developed areas, for disaster or flood-insurance payouts, the hurricane season of 2020 isn’t going to rival that of 2017, the year of Harvey, Irma, and Maria, or 2005′s Katrina, Rita, and Wilma.
But the damage to the program’s balance sheet may be permanent.
“The debt cannot be repaid from current premium revenue,” said Carolyn Kousky, executive director of the Wharton risk management center at the University of Pennsylvania. “The debt is incredibly unsustainable.”