The ‘T’ word: Models hint possible tropical or subtropical storm on the way

A caution flag warns swimmers as wind and rain from Subtropical Storm Andrea invade Dreissen Beach on Hilton Head Island in May 2007.

Hurricanes in May — nobody wants to mess with that. The Lowcountry, in fact, has never had a hurricane on record in the month before the official tropical season starts.

Tropical storms, though, do show up. And one might blow by next week. Long-range computer forecast models on Thursday hinted a storm system due to move off Florida could form the classic cyclonic pattern as it makes its way up the Atlantic coast.

If it were to become even subtropical, it could pass or make landfall here next Thursday.

What? In May? No way, you say. Forecasters agree, so far.

“This early in the season, there’s a pretty low probability that it would be something tropical. At this point, I really wouldn’t put much value in (the computer prediction),” said meteorologist Carl Barnes of the National Weather Service, Charleston.

National Hurricane Center forecasters were somewhat dismissive, too, that the system could bring any more than rain. That sort of storm is not unusual for this time of year, said Dennis Feltgen of the center.

But forecasters are “watching, nonetheless,” in the words of Mark Malsick, S.C. Climate Office severe weather liaison.

Whirling or not, the storm is a sign that weather patterns are simmering into the summer tropical stew in plenty of time for the June through November hurricane season.

And the early blow-up is a wake-up call for a year where strong El Nino conditions are suggesting it will be relatively calmer for storms. El Nino is a warming trend in the Pacific that creates shear winds in this hemisphere, the sort of winds that strip apart hurricanes.

Since record-keeping started in the 1800s, 23 tropical or subtropical storms have made brushes at South Carolina in May, according to S.C. Department of Natural Resources records. Thirteen of those storms overall came up the coast rather than across land from the Gulf of Mexico.

Nearly all were later in May, much closer to the June 1 start-up date than to May 1. But there are the outliers. Subtropical Storm Andrea made a pass on May 9, 2007.

Only one of the storms made landfall, records say, a storm that popped Beaufort on May 27, 1934. Originally classified a tropical storm on landfall, it was downgraded by the National Oceanic and Atmospheric Administration in 2012, according to NOAA records.

Reach Bo Petersen at 937-5744, @bopete on twitter or Bo Petersen Reporting on Facebook.