Already ravaged by Sandy, the Jersey Shore is on track to get exactly what it doesn't need: another siege of powerful, sand-removing onshore winds, perhaps gusting to 65 m.p.h.

A potent, winterlike storm - perhaps strong enough to generate snow in the immediate Philadelphia area - is almost certain to punish the region from Wednesday into Thursday, meteorologists are warning.

With high-wind and coastal-flood watches in effect, the likely upshot of what the National Weather Service is calling "a particularly dangerous situation" will be additional trauma for a region still picking up the millions of pieces from Sandy's destruction.

Although storm surges and wave heights would not be in a league with Sandy's, in Shore towns where dunes have been leveled, the storm is expected to set off fresh flooding.

Major coastal flooding again is possible, and moderate coastal flooding is likely, said Gary Szatkowski, meteorologist in charge of the National Weather Service office in Mount Holly.

The coastal storm expected to form Tuesday and intensify Wednesday would be a traditional nor'easter - named for the strong winds from the northeast that such storms generate - and not a "hybrid" like Sandy, born in the tropics and powered up in the mid-Atlantic.

Although the storm would not pack Sandy's unique powers, the wave attacks will last substantially longer, perhaps through three high tides, said Jon Miller, director of the Center for Maritime Systems at Stevens Institute of Technology.

Makeshift dunes piled on the beach after Sandy aren't likely to be much help, he warned, since they won't have stabilizing vegetation embedded in them.

"With a natural dune, it gets its strength from the plants," he said. "With the piles of sand, they are no more stable than any pile of sand that a kid builds on the beach with his bucket."

At the Shore and on the mainland after the unprecedented ravages of Sandy's winds, the prospective storm is raising anxieties about more power outages.

One of the more remarkable aspects of Sandy's hurricane-force gusts is that they somehow spared many leaves. Aesthetic considerations notwithstanding, the presence of those leaves represents a hazard because "it gives the wind more surface area to bring down the trees," Peco spokesman Ben Armstrong said.

The other wild card would be accumulating snow, which is possible well north and west of the city. Several inches could crown the Poconos, Szatkowski said, and snow could fall as far south and east as Philadelphia, although it probably wouldn't stick.

Armstrong said Peco officials are still rubbing their eyes in disbelief at Sandy's legacy.

"This is the most devastating storm in our history," he said.

Along with the record 850,000 outages in Peco's service territory, 463 poles were snapped, Armstrong said, some in open areas nowhere near trees that could have crashed into them. By comparison, Irene took down 190 poles. Armstrong said that so far, Peco has replaced 105 miles of cable.

As of Monday, about 640,000 New Jersey customers were without power, as were about 20,000 in Philadelphia and its suburban counties, most of them Peco customers.

Armstrong said that one thing that might hold down the numbers of outages if the coastal storm cranks up to its potential is the fact that Sandy undertook a major pruning operation.

"You would think that a lot of the stuff that would come down already has come down," Armstrong said. But not necessarily.

"We're closely watching this storm," he said.

Inquirer staff writer Jessica Parks contributed to this article.