A potent nor'easter that threatens the Jersey Shore with significant flooding, tropical-storm-force gusts, and beach-eroding waves could affect the entire region into Thursday with up to three inches of rain and perhaps even some snow, meteorologists warned Monday.

The National Weather Service posted a coastal-flood warning from 7 a.m. through 1 p.m. Tuesday, and with the ground still wet from a weekend soaking, the entire region was under a flood watch into early Wednesday.

"It's making me a little nervous," said Gary Szatkowski, meteorologist in charge of the Mount Holly weather service office.

Computer models indicated that the storm would pass close to the Shore, increasing the potential for flooding, so some towns could become variants of Venice by the sea for a time.

Gusts of 45 m.p.h. were possible along the coast, and strong onshore gusts could coincide with the morning high tide, scheduled for about 9 Tuesday.

"It may impact the schools," said Jim Eberwine, the Absecon emergency management coordinator and erstwhile Mount Holly meteorologist who has been briefing South Jersey county officials.

The weather service was predicting moderate flooding, which could result in widespread road closings in the Shore counties.

The powerful storm was forecast to form off the South Carolina coast Monday, generating strong winds onshore from the northeast - thus the term "nor'easter" - that would lash the Delaware and New Jersey coasts for several hours.

The models differ on the duration of the storm's effects, but meteorologists say it is possible that they are likely to linger into Thursday. Some wet snow could fall in the Philadelphia region by the time the storm winds down, and several inches were possible in the Poconos.

The wind should shift and come out of the north later Tuesday, easing the beachfront flood threat.

However, given the soaking rains, the threat along the brimming back bays would persist, said Eberwine. "The bays are chock full already," he said.

Even before the promised nor'easter ripened, the atmosphere was serving appetizers to parts of South Jersey and Delaware in the form of snow showers and tidal flooding Monday.

West Wildwood police advised motorists to move their vehicles to higher ground and announced the closing of the George Redding Bridge that leads in and out of the Wildwoods.

And while it wasn't exactly Buffalo revisited, some areas in South Jersey and Delaware did get a dusting of snow on Monday, and for a while, visibility was lowered along the Garden State Parkway, said the weather service's Kristen Klein.

As opposed to lake effect, the snow was the result of steady east winds blowing off the ocean, which also contributed to the tidal issues.

Said Klein, "We were a little bit surprised."

twood@phillynews.com

610-313-8210 @woodt15