NYC National Weather Service Issues First Flash Flood Emergency

The National Weather Service Office serving New York City issued a Flash Flood Emergency Aug. 1 evening, in the aftermath of Hurricane Ida, which sent dangerous downpours to the city.

New York City is vulnerable to flooding from huge storms, as three-fourths of the city is covered by impervious surfaces, so runoff is channeled into streets and sewers, reported The New York Times. The city’s century-old subway system design is also unprepared, so even on dry days a network of pumps pours out 14 million gallons of water from its tunnels and stations.

The New York City warning is the second ever issued.

The first Flash Flood Emergency ever issued by the New York office came Aug. 1 evening for Northeast New Jersey, reported ABC7NY.

The Flash Flood Emergency advised people to move immediately to higher ground, and avoid walking or driving through flood waters.

A Flash Flood Emergency is issued for the exceedingly rare situations, according to the National Weather Service. In the case of New York, this fits the bill due to extremely heavy rain, which poses a threat to human life, as well as catastrophic damage from a flash flood.

“In the era of climate change with extreme weather events, even the higher elevations are experiencing flash flooding,” said Metropolitan Transit Authority Acting Chair Janno Lieber, reported Bloomberg. “The big problem is drainage and sewer infrastructure gets overwhelmed.”

At least 22 people were killed as the remnants of Hurricane Ida impacted New York and New Jersey with tornadoes, record rain and flooding, reported NBC News. Flash flood waters overwhelmed homes and cars, and caused severe and widespread damage to property.

Four women, three men and a 2-year-old boy died in five separate flooding incidents in the city, according to police, reported NBC News.

In New Jersey, 14 other people were killed, including five residents at the Oakwood Plaza Apartments complex in Elizabeth and one person whose body was recovered in Passaic. It is unclear where or how these residents died, a spokesperson for Mayor Christian Bollwage confirmed to NBC News.

Central Park observed 3.15 inches of rain in one hour, from 8:51 pm to 9:51 pm, making it the wettest hour in New York City record-keeping, reported ABC7NY.