USA's 10-year hurricane drought is dumb luck

A major hurricane has not hit the U.S. in nearly 10 years — an occurrence that is "unprecedented in the historical record," according to a new study out this week.

Why is that? The study concludes it's mostly a matter of dumb luck: In the past decade, there have been many active hurricane seasons, as well as plenty of major hurricanes that either stayed out at sea or hit in the Caribbean and Mexico. (A "major" hurricane has wind speeds of at least 111 mph, a Category 3 or greater.)

"When we looked qualitatively at the nine-year drought, they aren't inactive seasons," said lead author Timothy Hall, a hurricane researcher at NASA's Goddard Institute for Space Studies.

There has been no significant change in the number of North Atlantic tropical cyclones, the amounts of energy powering them, nor any other hurricane metric, he said. "I don't believe there is a major regime shift that's protecting the U.S.," Hall said.

The decade-long drought beats the previous record of eight straight quiet years from 1861-1868, noted the study, which appeared in Geophysical Research Letters, a publication of the American Geophysical Union.

The most recent major hurricane to hit was Hurricane Wilma, which hammered Florida with 120-mph winds in October 2005, killing 61 people. Although we've seen some whopper hurricanes since then — such as Ike (2008), Irene (2011) and Sandy (2012) — none of them hit as a Category 3 or greater.

"I think that there has been a significant 'luck' component involved," said Colorado State University meteorologist Phil Klotzbach, who was not involved in the study. "But there has also been a predominant trough along the East Coast from 2006-2014, which has generated steering currents that have tended to push the storms away from the U.S. coast."

We also had several close calls, including Earl and Igor in 2010 and Ike in 2008, which was just below major hurricane status, he said.

But there's no way to predict what will happen this year, or any year. "Landfalling activity in one year is virtually completely independent of landfalling activity the prior year" Klotzbach said.

The quiet seasons, however, are a mixed bag, the study said. "The major-landfall drought is undoubtedly fortunate for coastal populations," according to the study. "A detrimental effect, however, may be a sense of complacency."

This year's forecast from Colorado State University is for a quieter year: only three hurricanes and a 28% chance of a landfall somewhere in the U.S.

But it only takes one big hurricane to make for a catastrophic hurricane season: Category-5 Hurricane Andrew was one of just four hurricanes in 1992, but it caused $26 billion in damage and killed 26 people.