The round of storms that touched down in the tri-state area Thursday night is being attributed to a weather phenomenon called derecho.
A derecho is a line of intense thunderstorms that produces a large amount of wind damage over a long distance. To be an official derecho, the line of storms must travel at least 240 miles and contain wind speeds over 58 miles per hour in concentrated areas.
Thursday's damaging storms traveled from western Pennsylvania to Long Island's Suffolk County, making a trek of over 240 miles in about five and a half hours.
Storm Knocks Out Power in NJ
The powerful storms brought very heavy rain in a short period of time and flash flooding. They also produced tremendous amounts of lightning, injuring at least one person, damaging dozens of homes and structures, and knocking out power to thousands across the tri-state.
When lightning struck a church steeple in Cobble Hill, Brooklyn, it knocked down large debris, seriously injuring a pedestrian below. He was taken to Long Island College Hospital.
"It appears as though it was a lightning strike that struck the steeple of the building, knocked several of the big blocks down, and they took out part of the scaffolding," said FDNY Deputy Chief Vinnie Mandela.
Storm Pounds Sullivan County
In Saddle River, N.J. a tree fell and took down a power line on Chestnut Ridge Road, sparking an electric fire that burned for hours. An accident on Route 23 in Franklin Borough was also attributed to the weather.
Residents in Bloombingburg in Sullivan County, N.Y. were still assessing damage after trees and wires were knocked down during the storm.
"We just saw like four big flashes -- it was red -- and it was the electricity hitting the water," said Pedro Arrieta, a 7th-grader who described a tree going into a neighbor's porch before it went into power lines.
In Hudson Valley, 25,000 Central Hudson customers were without power Thursday night. Some 1,890 Con Ed customers in New York City and Westchester experienced outages. On Long Island,1,326 LIPA customers had no electricity. Orange and Rockland customers had 4,998 customers without power, and PSEG saw 10,700 outages. NYSEG reported 52,730.
More than 800 flights were canceled in the eastern U.S. because of the storms.
Emergency officials say a tornado touched down in upstate New York just after 4 p.m. in the city of Elmira and there are reports of several buildings damaged.
A first round of storms thundered through the area Thursday morning, bringing quick, heavy downpours and multiple lightning strikes, one of which may have sparked a massive six-alarm fire in Brooklyn that critically injured one firefighter and hurt dozens more.
Consolidated Edison was responding to service outages and other emergencies. The utility and its union struck a deal Thursday to end the three-week lockout of 8,000 workers ahead of the approaching storms, Gov. Andrew Cuomo said.
Yet another round of strong storms will pummel the region Friday afternoon and evening. Those storms are not expected to be as intense.
Derechos typically happen once every two years in the tri-state area, though there was one in New Jersey on June 29 to June 30. While they can happen anywhere there are thunderstorms, they are more common in the Plains and Midwest.
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