5 people were killed by raging floodwaters in southeastern Pennsylvania. 2 children are still missing

Authorities in southeastern Pennsylvania are searching for a 2-year-old girl and her 9-month-old brother who vanished in raging floodwaters as a violent storm slammed the region.

The children and their family, who were visiting from Charleston, South Carolina, were driving to a barbecue when they got stuck in flash flooding, Upper Makefield Fire Chief Tim Brewer said Sunday afternoon. Their father and young sibling “miraculously” made it to safety, he said.

The children’s mother was found dead, Brewer said. Four other people were also killed by the flooding in Bucks County, authorities have said.

“With the five deaths due to the flood waters, mass casualty incidents like these, which we have never seen before, (are) unbelievably devastating to all the families involved,” Brewer said. “We are all grieving.”

“However, our commitment to finding the two children will still be unwavering,” he added. The children’s grandmother survived and was treated at a local hospital, Upper Makefield Township police said.

Local, state and federal authorities are assisting in search and recovery efforts in the area.

Southeastern Pennsylvania was hit hard by heavy rain Saturday, less than a week after parts of the state had again faced flash flooding that deluged roadways and displaced dozens from their homes.

Over the last month, parts of interior New England and the Northeast have seen 200% to 300% of their average monthly rainfall, leading to last week’s disastrous flooding event in parts of Vermont, New York and western Massachusetts.

Flood warnings issued in New York again

Flash flood warnings were also in effect across parts of southern Connecticut and southeastern New York until Sunday evening, less than a week after floodwaters killed a 35-year-old woman and caused millions of dollars in damage in the Empire State.

“New York State is once again seeing significant rainfall & we are prepared to help communities respond,” Gov. Kathy Hochul said on Twitter. “This rainfall is much more dangerous because the ground is already saturated.”

The New York City Emergency Management Department issued a travel advisory for Sunday, warning there was a risk for flash flooding in parts of the city and urged residents in flood-prone areas to be alert.

On Sunday afternoon, the governor pleaded with residents to avoid unnecessary travel.

“A flash flood doesn’t give you warning. It comes literally in a flash,” Hochul said. “And in those moments, your car can go from a place of safety to a place of death.”

Long Island’s Suffolk County saw 5 inches of rain over the course of two hours, the governor said.

The power is out in about 9,300 homes, mainly in Dutchess and Sullivan Counties, Hochul said, noting utility workers are trying to restore power.

“If you’re one of those 9,300 families without your power, it is a frightening time,” she said.

In parts of Connecticut, the heavy rainfall flooded roadways, stranding drivers who needed to be rescued by authorities, according to a Facebook post from the Bristol Firefighters Association.

“These storms are biblical in terms of the torrential rainfall you get and they’re happening more and more frequently,” Connecticut Gov. Ned Lamont said at a Sunday afternoon news conference in Bristol.

The National Weather Service has also cautioned most flood deaths occur in vehicles and urged people not to attempt to drive down flooded roads.

“Excessive runoff from heavy rainfall will cause flooding of urban areas, highways, streets and underpasses as well as other drainage areas and low lying spots,” the weather service said.

Major airports also experienced significant weather-related flight delays Sunday. All flights serving the major airports around New York City and Boston faced ground stops around 1 p.m., including Boston Logan International Airport, LaGuardia Airport, Newark Liberty International Airport and John F. Kennedy International Airport, according to the Federal Aviation Administration.

More than 1,500 flights within, into, or out of the US had been canceled by Sunday afternoon, and more than 8,000 were delayed, according to flight tracking website FlightAware.com.

Floods come just days apart

The latest round of devastation come as Northeast communities are still reeling from last week’s downpours.

Last week, Vermont faced flooding of the likes not seen since Hurricane Irene devastated the state in 2011. The intense rainfall gushed through streets and homes, prompting hundreds of evacuations and more than 200 rescues.

President Joe Biden approved an emergency declaration for Vermont, authorizing FEMA to move in needed equipment and resources.

Even with the help, “this is going to be a years – if not a decade – long recovery for the state of Vermont,” said Jennifer Morrison, the state’s public safety commissioner.

Flash flood warnings were again in effect earlier Sunday in parts of the state, prompting officials to warn of potential landslides.

“My team and I continue to monitor the situation as more rain falls in Vermont,” Gov. Phil Scott said on Twitter. “There are flash flood warnings throughout the state today. Remain vigilant and be prepared.”

Steady warming and atmospheric changes are “supercharging” regular weather events, making them longer and more intense, Michael E. Mann, a climate scientist and distinguished professor at the University of Pennsylvania, told CNN.

Climate experts say it is part of a “perfect storm” this summer, leading to deadly flooding in places like the Northeast while other parts of the world – including the Southwestern US – are scorched by record-breaking heat.

CNN’s Artemis Moshtaghian, Jennifer Gray, Samantha Beech and Michelle Watson contributed to this report.

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