When it rains, it pours.

Residents of the northeastern United States, still reeling from the havoc Sandy wreaked October 29 on the region, learned Wednesday that the same holds true for snow and wind, which buffeted the coast in the form of a nor'easter.

More than 600,000 households who have been without power since October 29 hunkered down for a long, cold night.

"While this storm is not as dangerous as Sandy was, New Yorkers should still take safety precautions today and tonight," New York Mayor Michael Bloomberg told reporters Wednesday.

By 10 p.m., some four inches of snow had fallen on Staten Island, the borough of New York that was hard hit by Sandy. Parts of Connecticut saw more than eight inches.

"It's Mother Nature's one-two punch," Cory Baker, mayor of Newark, New Jersey, told CNN's "Piers Morgan." "It's testing the resolve and the grit of my state and my city and, obviously, this region."

Some 25,000 residents of Newark had still been without power from Sandy, he said. "Now, this is being dumped; it has the potential to knock out more power within my state."

Indeed, that is what happened. Power outages in New York and New Jersey rose from 607,000 during the day to 652,000 customers by 10 p.m.

Soon after, Elizabeth Flagler, a spokeswoman for the Long Island Power Authority, said the company had tallied 100,000 new power outages since the storm began, bringing its total to 193,000.

"We're getting hit pretty hard between the snow and the wind," she said.

Forecasters predicted gusts of up to 60 mph in shore towns and cities across New York and New Jersey, bringing 2- to 4-foot storm surges just as homes and office buildings had begun to dry out and floodwaters to recede after Sandy.

Coastal erosion caused by last week's storm sparked fears of more flooding in storm-battered communities, while incoming cold weather was expected to hamper utility restoration efforts across the region.

Bloomberg urged residents in the city's low-lying areas -- especially Breezy Point, Hamilton Beach and Gerritsen Beach -- to "consider going someplace else tonight, to be a little bit on the safe side."

But he issued no mandatory evacuation orders, other than for a handful of chronic-care facilities and an adult-care center in areas that were hit hard by Sandy.

"If people think you're crying wolf, the next time, when it's really a serious threat, they might not do it," the mayor said.

That was not the case in New Jersey, where the Brick Township Office of Emergency Management had issued a mandatory evacuation order for all residents of low-lying waterfront areas of town.

Meanwhile, freezing temperatures ushered in snow and potentially deadly conditions for those without shelter, as displaced residents struggled to stay warm with generators and blankets. Others continued to camp with family and neighbors as they awaited the return of electricity.

On Tuesday night, about 8,500 Sandy victims had taken refuge in more than 100 Red Cross shelters. Temperatures were expected to dip again Wednesday night into the 20s, forecasters said.

Shelters were opened across the city for displaced residents or those without power.

"We think we're ready for anything," said Bloomberg, who ordered patrol officers to use their cruisers' loudspeakers to encourage elderly or homebound residents to go somewhere warm and safe and advised residents to check on neighbors.

More than a week after Sandy struck the Northeast, its death toll in New York City climbed to 41 as a 78-year-old man died Tuesday of injuries suffered in the storm, police said.

New York Gov. Andrew Cuomo fired his chief of emergency management, Steven Kuhr, for having arranged for the Suffolk County Office of Emergency Management to clear a tree from his driveway, a Cuomo administration source told CNN.

CNN was not able to reach Kuhr.

The continuing recovery effort had already left thousands of area residents tired, homeless and looking for answers.

New York City's Penn Station was shut for a time on Wednesday evening because of overcrowding after the Long Island Railroad halted service systemwide, Metropolitan Transit Authority spokeswoman Marjorie Anders told CNN.