Al Cope intently watched the radar scope for more than 10 hours.

A meteorologist with the National Weather Service in Mount Holly, Cope began his radar shift at 1 p.m. June 29, 2012, when a small cluster of thunderstorms first developed around Chicago. Ten hours later, that cluster had exploded and was sweeping toward the East Coast. What happened next was something Cope and many in South Jersey will never forget.

By the following morning, South Jersey had learned a new word, a word that still sparks flashbacks to 30 minutes of destructive fury. This week marks the five-year anniversary of the great derecho of June 29-30, 2012, a storm that left an indelible mark on the landscape of South Jersey and the minds of its residents.

The numbers tell the tale: 206,000 customers were left without power, according to Atlantic City Electric, some for more than a week, a fact made worse by a blistering nine-day stretch of 90- to 100-degree heat and humidity that immediately followed the storm.

Thousands of trees were uprooted, although there’s no official count. Vince Jones, Atlantic County’s emergency management coordinator, was amazed by the amount of destruction and its spread. One of the hardest-hit areas, Atlantic County was under a state of emergency for weeks, Jones said. Thousands of lightning strikes lit up the sky that summer night, something Jones remembers well.

“The lightning flashed so intensely, and a strange blue-purplish color I’ve never seen before,” he recalled.

The Atlantic City International Airport recorded a peak wind gust of 87 mph, but longtime Absecon resident and former National Weather Service meteorologist Jim Eberwine says that measurement doesn’t do the derecho justice.

“I think 100 mph winds or greater were most likely experienced in the strongest downbursts of the derecho,” he said.

That’s a conclusion he reached from a walking tour of the damage at first light the following morning, from the streets of Absecon to the Mays Landing Golf and Country Club in Hamilton Township. A notebook and measuring tape in hand, Eberwine had conducted many storm surveys when he was with the National Weather Service, and knew just what to look for.

“What impressed me was not only the number and the diameter of the trees that were entirely uprooted or snapped, but the fact that they were so many live and healthy trees fallen — not just dead ones,” Eberwine explained.

He also knew what else to bring with him: a copy of the Enhanced Fujita scale, which is used to measure the intensity of tornadoes.

Eberwine immediately says there was no evidence of a tornado, but the scale helps meteorologists analyze storm damage, and place an estimated intensity on the peak winds.

And while many residents, even Jones, initially thought it was a tornado based on the ferocity of the storm and intensity of the damage, Cope says we would have fared much better if it had been a twister.

“A tornado only affects a narrow path, let’s say 50 to 100 yards wide and a mile long, while a derecho will affect hundreds of square miles,” Cope explained.

In Spanish, the word derecho means “straight.” That’s fitting, since the defining characteristic of a derecho is the intense straight-line winds it produces.

The word first was used for a destructive thunderstorm complex way back in 1887, Eberwine said. But the word has only recently entered mainstream meteorology, with the June 2012 derecho certainly magnifying the word’s use.

New Jersey does see a derecho every two to four years, Cope said, but few will ever rival the intensity of the June 2012 storm.

Along the shore, the defining storm of this generation is Hurricane Sandy, and the five-year anniversary of her landfall now just four months away.

But on the mainland across Atlantic, Cumberland and Salem counties, the derecho was the big one, the measuring stick for all future storms.

Contact: 609-272-7247 DSkeldon@pressofac.com

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