(MCT) PHILADELPHIA — Sandy, now spinning its way toward retirement, shared similarities with a legendary predecessor, the “Perfect Storm” of October 1991. But meteorologists say the two differed in one important respect: Sandy was far worse.
“This storm is going to be in a class of its own,” Louis W. Uccellini, director of the National Centers for Environmental Prediction, said Tuesday.
That might get an argument from some on the mainland, but probably not from residents and property owners along the Jersey Shore, or the inhabitants of the new Venice of the Northeast, New York City.
In the coming weeks, Sandy’s legacy will become more evident as bills for federal disaster relief start piling up.
In an extraordinary move, without waiting for damage surveys, President Barack Obama already has declared a “major” disaster for New Jersey and New York coastal areas. Damage could reach $20 billion, according to Eqecat Inc., a California insurance-modeling company.
Sandy’s statistical accomplishments are impressive. Record power outages (3.7 million customers in the region); record-low air pressure over Philadelphia, evidence of the storm’s intensity; new standards for storm surges; and an all-time high-water mark on the Delaware River at Philadelphia (10.2 feet).
But it was Sandy’s behavior that has the meteorological community buzzing. Sandy defied the traditional rules of weather by moving from east to west, and that peculiar path probably had something to do with blunting its effects away from the coast, especially north and west of the city.
And its peculiar nature — an explosive combination of hurricane and nor’easter-like cyclone — had everything to do with the flood tides at the Shore and the inundation and shutdown of the New York subway system.
Sandy was so strange that meteorologists are unsure what to call it. The National Hurricane Center has determined that even though its peak winds were strong enough to qualify as a hurricane when it made landfall, it was behaving too much like a winter-type storm by then to be called tropical.
Hurricanes are not snowmakers, but on Tuesday a Sandy-related blizzard was raging in the mountains of West Virginia. Sandy was circulating so much cold air that temperatures did not get out of the 40s in gloomy Philadelphia on Tuesday, even though winds were from the usually warmer southeast.
“I don’t believe there’s anyone alive who’s seen this,” said Gary Szatkowski, meteorologist in charge of the National Weather Service.
Last week, meteorologists differed on the forecast details, but by Friday they generally agreed on the big picture: Sandy would move slowly north off the East Coast, make a drastic turn to the west near Delaware or New Jersey, interact with deep storm moving across the East, and move inland.
That scenario played out for the most part, but Sandy had a few surprises. After it gained fresh energy crossing the Gulf Stream, it got caught in upper-air winds that sped up its trip toward land, said AccuWeather Inc. meteorologist Brian Edwards.
“Having that system accelerate didn’t do you any favors,” Uccellini said. Since the winds were moving in the same direction as the storm, west to east, Sandy’s motion increased the wind speed. A gust of 89 mph was measured at Surf City, N.J., as were gusts of 76 mph as far inland as Bensalem, Bucks County, Pa., and 68 mph at Philadelphia International Airport.
Tropical-cyclone winds typically affect smaller areas than do winter storms. But when Sandy reached Atlantic City, N.J., it had merged with the land storm and was acting like a nor’easter, with a massive circulation.
Sandy’s winds, covering nearly the eastern third of the nation, agitated waves that drove floodwaters into Manhattan, and pounded away at Long Island and New York Harbor.
The computer forecast models were dead-on with their projections for wind speeds at the Shore and in the Philadelphia region, but off in terms of duration and on inland rainfall totals.
The winds let up hours ahead of predictions Tuesday morning. Up to a foot of rain fell at the Shore, but generally it was 2 to 5 inches west of the Delaware.
Meteorologists said that the models were having trouble with a storm that was making a transition from a tropical storm — one fueled by warm waters — and a wintry storm, one powered by temperature contrasts. Szatkowski said the models may have underrated the weakening effects of the trip across land.
“One of the more difficult aspects of the forecast was getting a handle on the wind field,” Szatkowski said.
Sandy “clearly will go down as a historic storm,” Uccellini said. Whether it will go down as a hurricane is another matter. Officially, the hurricane center declared it a post-tropical storm at landfall.
Barry Evans, chief executive officer at AccuWeather, said Tuesday that the distinction was unnecessary and confusing to the public.
Uccellini countered that it would be confusing to label something a hurricane if it was not. He added, however, that the storm would be examined closely and that eventually it could gain that title officially.
Tony Gigi, a veteran meteorologist, said that the effects were the same no matter what Sandy becomes in the record books.
“This hammered the coast the way a hurricane would,” he said, “no matter what you want to call it.”