Jersey Shore Braces for Severe Flooding as Weekend Snowstorm Approaches

— -- The New Jersey Shore, one of the hardest hit areas from Super Storm Sandy in 2012, is now bracing for potential flooding in this weekend's impending snowstorm.

A coastal flood warning has been issued for Delaware, New Jersey and the southern coast of Long Island.

But the worst coastal flooding and erosion is expected in southern New Jersey, where some coastal areas could see record flood levels.

This video shows a drone flying over emergency dune construction on the Belmar, New Jersey, beach Thursday, in preparation for the weekend:

Officials are also building up sand dunes in Toms River, New Jersey, where hundreds of first responders are on standby, according to ABC station WABC-TV in New York.

"We're going to get the flooding and we're going to get the high winds," Paul Daley of the Toms River Office of Emergency Management said, according to WABC-TV. "These are high water rescue trucks...we did learn some things from Sandy -- we didn't have enough of these and we had to actually borrow from other towns."

Further south, in Barnegat Township, New Jersey, the Barnegat Township Police Department issued a mandatory evacuation notice for some residents.

Residents were told to evacuate no later than 10 p.m. today, police said.

Lt. Keith Germain of the Barnegat Police said earlier that town officials were also worried about power outages, according to WABC-TV.

As the shore prepares for the storm, New Jersey Gov. Chris Christie, who’s in New Hampshire campaigning for the Republican presidential nomination, decided to return to his state this afternoon.

"I'm sorry, NH but I gotta go home - we got snow coming," Christie tweeted.

"But I will be back, because I am able to do both things. The fact is - you are never not the governor," he wrote.

Christie was on the fence earlier today about leaving New Hampshire, explaining, “This is not something that New Jersey hasn’t dealt with multiple times every winter for every winter that I’ve been governor and this has been a state that has dealt with Hurricane Irene and Hurricane Sandy."

New York City Mayor Bill de Blasio, a Democrat, told CNN this morning that Christie “needs to come back.”

"A day or two ago it might have been a question mark, right now it’s not a question mark anymore,” de Blasio said on CNN this morning. “Obviously we are being warned it could be even worse. We find this out with each storm. Sometimes it's less than we expected, sometimes it’s more. For any governor, it’s time to come home."

ABC News' Veronica Stracqualursi contributed to this report.

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