October 2, 2015 by Canadian Underwriter
The transforming Hurricane Joaquin slowly tracking through the Bahamas is reminiscent of Hurricane Irene four years ago, but the latest storm is affecting Bahamian islands where insurance up-take is low, which will help limit insured losses, suggests a statement issued Thursday by AIR Worldwide.
Originally classified as a tropical depression on Sept. 27, Joaquin developed into a Category 1 hurricane Thursday, undergoing rapid intensification to become a Category 4 storm, AIR Worldwide reports. It was expected to further intensify before later weakening to tropical storm strength.
“Hurricane Joaquin is reminiscent of Hurricane Irene (2011), which impacted the central Bahamas as a Category 3 hurricane,” Scott Stransky, manager and principal scientist at AIR Worldwide, notes in the statement. “Although roof damage was prevalent as a result of that storm, there was very little structural damage due to the well-built properties in the Bahamas,” Stransky points out.
A damage survey in the Bahamian islands following Irene was carried out and, as expected, AIR Worldwide found that “wind damage to well-built concrete structures was limited to roofs, while less prevalent wooden structures suffered more substantial damage. Commercial properties suffered significant damage to signage.”
While take-up rates in New Providence Island (Nassau) and Grand Bahama Island (Freeport) are high, take-up is quite low on other islands, which are being impacted by Joaquin. “This should help limit insured losses,” notes the statement from AIR Worldwide.
The Bahamas Building Code, implemented in the early 1970s, closely follows that of the South Florida Code. The enforcement of the Bahamas code is very stringent, which helps limit severe structural damage, AIR Worldwide reports.
Most houses in the Bahamas are of concrete block or poured concrete construction, although unreinforced masonry and timber construction are also used. Roofs are usually covered with asphalted wooden roof tiles, but corrugated iron and aluminum roofs and Spanish tile are not uncommon. Most residential dwellings are single-story, while commercial buildings can be mid- or high-rise.
A public advisory issued Friday morning by the U.S. National Hurricane Center (NHC) noted that Joaquin was extremely dangerous, moving slowly northwestern as it batters the central Bahamas. Hurricane conditions were expected to continue over the central Bahamas Friday.
The maximum sustained winds are near 130 mph (215 km/h) with higher gusts, states the advisory. “Joaquin is a dangerous category 4 hurricane on the Saffir- Simpson Hurricane Wind Scale. Some fluctuations in intensity are possible during the next 24 hours. Slow weakening is expected to begin on Saturday.”
NHC points out that a hurricane warning – tropical storm conditions are expected somewhere within the warning area – is in effect for Central Bahamas, Northwestern Bahamas, including the Abacos, Berry Islands, Eleuthera, Grand Bahama Island, and New Providence, and the the Acklins, Crooked Island and Mayaguana in the southeastern Bahamas. A hurricane watch – hurricane conditions are possible within the watch area – is in effect for Bimini and Andros Island, the advisory adds.
“What Joaquin will do once it departs the Bahamas remains highly uncertain,” AIR Worldwide’s Stransky says. Noting that the forecast tracks have generally shifted eastward since Wednesday, the storm could track toward “the Carolinas with a possible landfall there or in the Mid-Atlantic states as a hurricane on Monday, or New England as a tropical storm on Tuesday,” he continues.
“As Joaquin moves northward, it will encounter cooler water and increased wind shear, both of which should weaken the storm. Other mitigating factors include the possibility of eyewall replacements and the inclusion of dry air,” he adds.
On the forecast track, notes the NHC advisory, the core of the strongest winds of Joaquin will continue moving over portions of the central and northwestern Bahamas today. It is expected Joaquin will begin to move away from the Bahamas tonight and Saturday.
“A very dangerous and life-threatening storm surge will raise water levels by as much as six to 12 feet above normal tide levels in the central Bahamas in areas of onshore flow. A storm surge of two to four feet above normal tide levels is expected in the remainder of the Bahamas within the hurricane warning area. Near the coast, the surge will be accompanied by large and dangerous waves,” the advisory notes.
Swells have begun to affect portions of the southeastern coast of the U.S. and will spread northward along the east coast through the weekend.
“These swells are likely to cause life-threatening surf and rip current conditions,” the advisory states. “Regardless of Joaquin’s track, a prolonged period of elevated water levels and large waves will affect the mid-Atlantic region, causing significant beach and dune erosion with moderate coastal flooding likely.”