WASHINGTON CROSSING, Pa. — Emergency crews in suburban Philadelphia intensified their search Monday for a missing 9-month-old boy and his 2-year-old sister who were swept away in a family car when torrential rains flooded a roadway.

While the East Coast grappled with the aftermath of downpours that closed roads and rendered the water supply undrinkable in places, the West and other parts of the country contended with sizzling temperatures and unsafe air quality attributed to Canadian wildfires.

In eastern Pennsylvania, authorities described Monday’s search for missing Matilda Sheils, 2, and her 9-month-old brother Conrad Sheils as a “massive undertaking” including 100 search crew members and numerous drones dispatched along a creek that drains into the Delaware River. The children are members of a Charleston, South Carolina, family that was visiting relatives and friends when they got caught in a flash flood Saturday.

The Tragic Incident

“As they tried to escape the fierce floodwaters, dad took his 4-year-old son while the mother and the grandmother grabbed the two additional children,” said Upper Makefield Township Fire Chief Tim Brewer. While father and son made it to safety, “the grandmother, the mother, and the two children were swept away by the floodwaters,” he said.

The children’s mother, Katie Seley, 32, was among at least five people killed in the flooding, while the grandmother survived, Upper Makefield Police said in a social media post. The other victims’ names have not been released.

The Community’s Response and Support

Monsignor Michael Picard of St. Andrew Roman Catholic Church, where family members are parishioners, said he spoke with the grandparents Sunday. The grandfather attended morning Mass on Monday, where the family was included in prayers.

“No matter how long I’ve been doing this — over and over and over, many, many years — you find yourself still helpless and without words to make people feel more comfortable,” Picard said. “And so you just simply pray with them for a few minutes.”

Pennsylvania’s deadly flash flooding called to mind torrential rains that killed at least 25 people in New Jersey when the remnants of Hurricane Ida passed through the state in 2021. People abandoned cars along washed-out roadways as muddy waters overtook driving lanes and flooded low-lying houses.

Flash Flooding Across the Northeast

Other parts of the saturated Northeast began drying out Monday after drenching weekend rains resulted in flash flooding in parts of New Hampshire, Massachusetts, Connecticut, New York and New Jersey. New Jersey Gov. Phil Murphy declared a state of emergency Sunday and planned to tour damaged areas Monday in the northwest part of the state.

A confirmed tornado touched down Sunday morning in North Brookfield, Massachusetts, but no injuries or major property damage were reported. In New Hampshire, where some roads caved in, heavy rain postponed Sunday’s NASCAR race at the New Hampshire Motor Speedway.

Vermont reported no immediate safety threats following historic flooding nearly a week ago that dumped up to two months’ worth of rain in two days. However, the Federal Emergency Management Agency received a request to provide water for almost 8,000 people for three days, which the Vermont National Guard distributed. As of Friday, emergency personnel had also delivered 1,200 gallons to Copley Hospital in Morrisville after the town issued an advisory warning people not to drink local water because of the flooding.

U.S. Transportation Secretary Pete Buttigieg planned to visit the state later Monday.

The Vermont Emergency Management agency reported that swift-water rescue teams conducted an additional six rescues overnight. The agency also was monitoring areas at risk for landslides.

More rain was in the forecast for Tuesday.

Flight Disruptions Due to Severe Storms

Sunday’s strong storms led to hundreds of flight cancellations at airports in the New York City area, and hundreds more flights were delayed.

New York Gov. Kathy Hochul said 5 inches of rain fell within two hours in Suffolk County on Long Island. The state saw $50 million in damages from storms in the past week.

In North Carolina, floodwaters were blamed for the death of a 49-year-old woman whose car was swept off a road in Alexander County late Saturday night. A man who was in the car with her was rescued.

Meanwhile, extensive swaths of the northern United States awoke to unhealthy air quality Monday morning or were experiencing it by midafternoon, according to the Environmental Protection Agency’s AirNow.gov Smoke and Fire map.

Fine particle pollution caused by smoke from Canada’s wildfires is causing a red zone air quality index, meaning it is unhealthy for everyone. The particles, known as PM2.5, are tiny enough to get deep into the lungs and cause short-term problems like coughing and itchy eyes, and in the long run, can affect the lungs and heart.

Concerns Over Unhealthy Air Quality

The EPA advises keeping outdoor activities light and short when air quality indexes reach above 150 on the agency’s map. On Monday afternoon, cities and regions hitting that mark included Lincoln, Nebraska; Peoria, Illinois; Fort Wayne, Indiana; Cleveland and Columbus in Ohio; Huntsville, Alabama; Knoxville and Chattanooga in Tennessee; Greensboro, North Carolina; Pittsburgh, Pennsylvania; and Syracuse and Utica in New York.

Sensitive groups, including people with heart and lung disease, older adults, children, and pregnant women, should consider staying inside, advisories warn.

Power Outages and Heatwaves in the Midwest and West

Elsewhere in the U.S., thousands of people in Kansas and Missouri were without power from weekend storms that swept those states. Kansas’ largest electric power provider, Evergy, said it could take days to restore service to all customers. The timeline could create difficult conditions for some people as more storms and stifling heat were expected in Kansas and Missouri early this week, according to the National Weather Service.

In the west, temperatures in Death Valley, which runs along part of central California’s border with Nevada, reached 128 degrees Fahrenheit on Sunday at the aptly named Furnace Creek, the National Weather Service said.

Reno, Nevada, set a record high of 108 degrees for the date on Sunday, while also tying the all-time high set on July 10 and 11 of 2002, and equaled on July 5, 2007, the National Weather Service said.