Operators at the Oyster Creek nuclear reactor in Ocean County declared an alert around 9 p.m. due to rising at the plant's intake structure. The plant has been shut down for a week, and Exelon Corp. said in a news release that there was no threat to public safety or the plant's equipment.
In the Philadelphia suburbs, Bucks and Montgomery Counties bore the brunt of the outages all day, and suffered a sharp increase Monday night. By 11:50 p.m., Bucks County had at least 195,000 residents without power and Montgomery County had at least 177,000.
"It's probably going to be the largest storm damage in PECO's history," said spokesman Fred Maher. "With the ground saturated, it's a serious combination for us as far as outages."
Outages mounted in the city of Philadelphia as well. The Northern Liberties/Fishtown area did not lose all power, but residents could see the sky lighting up with green flashes from blowing transformers, and hear buzzing sounds from blocks away.
Throughout the afternoon, the number of people without power across the tri-state area doubled, tripled, and quadrupled every few minutes - even as utility crews were bringing some customers back online.
Hurricane Sandy - now a tropical storm - could go into the record books in terms of power outages, officials fear, having toppled power lines in a half-dozen or more states, especially New Jersey, Pennsylvania, Delaware, and New York.
Full restoration could take more than a week - through Election Day.
Note that the figures below do not include tens of thousands of customers who have already had their power restored across the region.
Peco outages have risen to about 570,000, with about 195,000 of those in Bucks County. Montgomery County had 177,000 outages, Delaware County 85,000, Philadelphia County 55,000, and Chester County 58,000. (To report an outage: 1-800-841-4141.)
FirstEnergy providers elsewhere in Pennsylvania reported more than 246,000 outages. Service was out entirely for their 7,300 customers in Bucks and Chester counties.
Atlantic City Electric had more than 195,000 homes and businesses in the dark across the southern part of South Jersey, from Gloucester County to Long Beach Island. Nearly 85,000 people in Atlantic City remained without power. (AC Electric customers can report outages at 1-800-833-7476.)
Jersey Central Power & Light had 911,000 outages across the state.
PSE&G has 700,000 customers without power, due to extreme winds and storm surge. (To report an outage: 1-800-436-7734.)
PPL Electric, which serves most of eastern Pennsylvania, saw outages more than double after 9 p.m. By 11:30 p.m., 348,000 homes and businesses were without power - including 114,000 in Lehigh County and 62,300 in Northampton County. (To report an outage: 1-800-342-5775.)
Delmarva Power & Light, which serves Delaware and Eastern Maryland, had 76,000 customers without power. (To report an outage: 1-800-898-8042 for New Castle County, 1-800-898-8045 for Kent and Sussex Counties.)
Contact staff writer Jessica Parks at firstname.lastname@example.org. Inquirer staff writer Allison Steele contributed to this report.