Weatherwatch: back-to-back hurricanes to become norm in US

Two storms in same place within fortnight will be twice as likely on US Gulf coast by end of century, study finds

Next Tuesday will mark the end of the Atlantic hurricane season (not that hurricanes take notice of the date, of course), and it has been a busy year. With a total of 21 named storms – seven of which became hurricanes – it has been the third most active season on record and the fourth costliest, causing an estimated $70bn (£52bn) in damages. And it is only the third time ever that all 21 designated names – a practice dating back to 1953, using six recycled lists – have been used.

But relentless hurricane seasons are something we will have to get used to. Dazhi Xi and Ning Lin from Princeton University looked at hurricane records dating back to 1979 and showed that back-to-back storms (two storms in the same place within a fortnight) had become more likely over time, with Florida and Louisiana being the states at highest risk. Using a climate model to project this trend into the future, they found that back-to-back storms will be twice as likely along parts of the US Gulf coast by the end of the century (the findings were published in Geophysical Research Letters).

“If you need 15 days to restore infrastructure – for example, a power system – after a storm hits, and the second storm makes landfall before the system can recover, residents will face dangerous conditions,” said Xi.