Hanna Becomes Hurricane Then Stalls; Heads for Georgia, South Carolina

According to catastrophe risk modeling firm AIR Worldwide, storm development in the tropical Atlantic was even more active on Tuesday than it was on Monday.

Shortly after Gustav came ashore in Louisiana on Monday, Hanna began battering the southeastern Bahamas with hurricane force winds. Hanna became the fourth named hurricane of the 2008 season before slowing to being downgraded back to a tropical storm.

Shortly thereafter, Tropical Storm Ike was named.

On Tuesday morning, forecasters at the National Hurricane Center began tracking a tropical depression off the coast of Africa. Now upgraded to tropical storm Josephine, it is the tenth named storm of the season. Josephine’s sustained winds are near 40 m.p.h. and further strengthening is forecast.

Hanna was upgraded from a tropical storm to a hurricane on Monday afternoon and was downgraded again on Tuesday to a tropical storm.

As of 8 p.m. EDT on Tuesday, Hanna was located in the southeastern Bahamas and about 450 miles southeast of Nassau. Maximum sustained winds were near 65 m.p.h.

“Hanna had successfully fought off wind shear on Monday to become the fourth hurricane of the 2008 season,” said Dr. Peter Dailey, director of atmospheric science at AIR Worldwide. “The storm then stalled over the sparsely populated southeastern Bahamas, held in place by a large area of high pressure extending from the Great Lakes southward.”

Dailey said Hanna’s “slow and meandering motion” is expected to continue for the next 24 to 36 hours before it turns to the northwest.

Hanna is dumping 4 to 8 inches of heavy rain on the southeastern Bahamas, the Turks and Caicos Islands, and Haiti, which was already saturated by rain from Gustav last week.

However, AIR said the forecast models are in reasonably good agreement that by Wednesday Hanna will speed up and eventually make a U.S. landfall somewhere between Savannah, Georgia and Myrtle Beach, South Carolina.

Until then, there is considerable uncertainty with respect to Hanna’s track through the Bahamas. The NHC’s most likely track has Hanna skirting the Bahamas to the north and well away from the most heavily populated islands of New Providence (and the capital Nassau) and Grand Bahama. Other models show a more southernly track directly through the middle of the islands.

Meanwhile, Gustav—now a tropical depression centered over northwest Louisiana—continues to drop heavy rain over portions of Texas, Louisiana, and Arkansas. However, local officials are relieved that apart from some overtopping of the Industrial Canal in New Orleans’ Lower Ninth Ward, the city’s floodwalls seem to have survived largely, if not entirely, intact.

AIR Worldwide
www.air-worldwide.com