Quiet spell for storms may be over soon in S.C. Scientists point to cycles, La Nina trend

Hurricane Joaquin contributed to historic rain and flood tides in South Carolina and North Carolina as it passed offshore in October 2015.

The earliest hints of the upcoming hurricane season aren’t reassuring, even going back three centuries to the days of “the Occupation Storm.”

The years that storms made landfall in South Carolina, or did damage in passing, tend to run in cycles, suggests an analysis by Cary Mock, University of South Carolina geography professor.

The current 11-year run of “quiet” years is the fifth longest on record dating back to 1722.

The longest “drought” was 19 years, from 1960 to 1979, Mock said.

The shortest would be zero, or years in which more than one storm struck. There have been only two intervals of 12 years.

Meanwhile, the strong El Nino warming trend in the Pacific is forecast to be waning by the spring or early summer, and the reverse La Nina cooling trend in place by the fall, according to the National Oceanic and Atmospheric Administration. Persistent shear winds stirred by El Nino have been largely credited by meteorologists for keeping cyclones from developing. The winds would be expected to die down as the warming fades.

“Following three quiet Atlantic hurricane seasons in a row, there is considerable uncertainty” whether the atmospheric conditions that quelled hurricanes will continue, said Phil Klotzbach of the Tropical Meteorology Project founded by hurricane guru Bill Gray, in a periodic update filed late last year that took note of the forecast El Nino change.

The sort-of-silver linings are that the cycles “are not really precise,” Mock said. And climate conditions don’t seem to be a big factor in whether a storm takes a shot at the state.

“It’s random,” he said. “You just need the right set of weather patterns to make a hurricane hit.”

The Occupation Storm was a documented 1781 tropical cyclone that has been studied but never really categorized as a hurricane. Mock’s research of it suggested it was, he said. A destructive storm surge that sank a lot of ships was a deciding factor, he said. “And (the storm) was widespread.”

The storm was named because it struck the year after Charleston surrendered to the British in the Revolutionary War. An account of the blast in the “Royal Gazette,” the British-run newspaper at the time, reads, “Between 8 & 9 it blew fresh, accompanied by rain. It continued to rain and blow from the same quarter with increasing violence during the whole night and yesterday, till one’o’clock when the wind shifted to the east-northeast.”

Two British ships sank at the docks where they were moored, said Tom Rubillo, in “Hurricane Destruction in South Carolina, Hell and High Water.” One was later raised.

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