Authorities urged people to stay off the roads as abandoned cars hindered plows and snow drifted onto previously cleared surfaces, making driving treacherous.
"That's a problem statewide," said State Police spokesman Sgt. Julian Castellanos.
New Jersey Transit said it would resume bus service Tuesday morning, but warned riders to expect delays. It said trains would run on a reduced schedule for a second day Tuesday.
It was uncertain when passengers would be able to depart on flights from Newark Liberty International Airport. The Port Authority of New York and New Jersey said flights were expected to begin arriving Monday evening, but only a limited number of departures were expected Tuesday.
Electric utilities reported about 3,000 customers without power statewide as of 8 p.m. Monday. That's down from a high of about 10,000 earlier in the day.
Authorities rescued hundreds of stranded motorists since early Sunday.
Among those rescued were passengers on two buses that were headed from Atlantic City headed to Manhattan when they became stuck around 6 p.m. Sunday in the express lanes of the Garden State Parkway in Holmdel. One bus was finally freed just before 7 a.m. Monday, while those aboard the second bus were put on other buses around 11:30 a.m. Monday and driven to safety.
Sgt. Stephen Jones, a state police spokesman, said each bus had about 50 people on board, including some diabetics and elderly people. When ambulances could not reach the buses, mostly due to abandoned vehicles blocking the road and snow drifts of up to five feet, state troopers bought water and food and gave the items to passengers who were feeling ill or lightheaded.
"Most of the people are pretty calm, but they were getting antsy," said trooper Chris Menello, who was among those trying to aid the passengers. Fortunately, the buses had enough fuel to keep running overnight, and passengers were able to remain warm and somewhat comfortable.
Menello said the traffic jam started around 5 p.m. Sunday evening with a woman who went into labor in a car. Traveling with the woman were her husband and their three small children.
An ambulance was able to reach the woman and bring her to the nearby Bayshore Medical Center so she could have her baby, Menello said. But by then the Parkway had become a parking lot, with accumulating snow preventing people from digging out.
When the woman's husband pulled their car to the side of the road, a log jam started, eventually stranding both passenger buses, as well as about 30 vehicles and a tractor-trailer in the express lanes.
The snow was so bad along the shore, that even tow trucks needed help.
"We're sending out front-loaders to the tow yards to get them out," said Menello, who said the storm was the worst he's encountered in his five years with the state police. "It's harsher and faster than anything I've seen."
State Senate President Stephen Sweeney, serving as acting governor with Gov. Chris Christie and Lt. Gov. Kim Guadagno out of state, declared a state of emergency Sunday night and ordered state government offices closed on Monday, citing the treacherous travel conditions. The storm also shuttered the state's court system, and most businesses in the state were closed for at least part of the day.
"It's been a real battle," said Sweeney, who was governing Monday from his office in Westville. "The biggest problem now is the wind."
Dangerous conditions were reported across the state Monday.
Castellanos said I-280 in northern Jersey remained closed in both directions in the West Orange area as authorities worked to plow the highway and remove as many as 40 abandoned vehicles. Castellanos said all the motorists had been rescued and taken to shelters.
Flights in and out of Newark were canceled Sunday and Monday. Dozens of people lay on the floor of the airport's concourse, leaning their heads against their luggage as they waited for ticket counters to open.
In the Terminal C baggage claim area, melting snow was leaking through the roof and pitter-pattering into a trash can that workers had positioned near carousel 6. Two pigeons walked among the sleeping passengers on the floor, looking for crumbs.
While most people didn't venture outdoors, those who did found the treacherous roads to be slow-going - or worse.
Raquel and Amir Dayan had to get help digging out after ending up in a median along Interstate 195 as they attempted to travel from their home in Philadelphia to her parents' place in Oakcrest. The falling snow was so blinding the couple didn't realize they'd left the road at first.
"You couldn't see anything. We just kind of stopped moving," Raquel Dayan said.
Castellanos said road crews had reopened one lane in each direction near the eastern end of I-195 in Howell Township Monday afternoon. Drifts as high as 8 feet had completely blocked the road, he said.
Associated Press writers Geoff Mulvihill in Cherry Hill, Bruce Shipkowski in Trenton, Samantha Henry in New York City, Angela Delli Santi in Hamilton Square and Chris Hawley in Newark and photographers Julio Cortez in Newark and Mel C. Evans in Columbus contributed to this report.