On Long Island and in New York City, 2 to...

On Long Island and in New York City, 2 to 3 inches of rain are forecast, possibly causing areas with poor drainage to flood, as well as moderate coastal flooding and beach erosion. Credit: NWS

New York State agencies are gearing up for a Thursday-to-Saturday nor’easter that could drench and blast Long Island with rain and high winds and envelop upstate with snow, officials said.

In a first, the nearly 20-feet high flood gates that protect the north and south entrances of Nassau’s Bay Park Sewage Treatment Plant will be shut, according to County Executive Laura Curran, though the storm looks like a featherweight compared with superstorm Sandy of 2012.

Since Sandy inundated the plant, a berm-concrete wall was built around it, and the gates have been ready for about a year.

Suffolk County Executive Steve Bellone noted the full moon could increase storm-driven high tides. “We’re readying and deploying a number of our high-access vehicles in case they need to be deployed to assist individuals in flooding situations,” he said by telephone Thursday afternoon..

Resembling Humvees, those vehicles can handle high water.

Town of Riverhead Supervisor Laura Jens-Smith in a statement said: “Tides will be 1 ½ to 3 feet above normal on top of the astronomical high tides and will occur around the noon and midnight hours.”

Bellone said restoring electricity, if the wind and rain downed power lines, could be another problem. Fire, rescue and other emergency personnel will open Suffolk’s Yaphank-based emergency operations center at 8 a.m. on Friday; municipal and agency representatives should join them by noon, he said.

Nassau also listed other preparations: cleaning flood-prone catch basins, steadying traffic lights, readying generators, topping up vehicles — and moving any located in low-lying areas to higher ground. Suffolk said outer beaches, such as the ones in Smithtown, were closed until Sunday.

Gov. Andrew M. Cuomo activated the state Emergency Operations Center ahead of the storm, saying, “As the saying goes, March is coming in like a lion, and we are preparing for heavy snow, rain and flooding across New York this weekend.’ ”

He added, “As we are preparing for whatever Mother Nature throws our way, I am asking for everyone to listen to weather forecasts in your community and take the necessary precautions to prepare for conditions.”

State and local officials all pledged to scrutinize the storm’s track, as it can shift unexpectedly.

The U.S. Geological Survey said it undertook a “last-minute deployment,” placing 12 storm-tide and wave sensors in Long Island waters, along with other monitors from Delaware to Maine.

PSEG Long Island said it is staffing up with 705 line and tree workers, including 300 FEMA contractors, and 50 other contractors.

The Long Island Rail Road said it was ensuring workers were on hand to clear fallen trees, pump flood-prone areas, fix power outages and run standby diesel locomotives. The railroads “are prepared to suspend service in segments or in whole, if needed,” Cuomo said. The Port Authority, which has vowed to fix the myriad problems that arose at Kennedy Airport after the last big storm, said it was coordinating with local, state and federal officials. The authority said it would send workers and equipment to its airports, bridges, tunnels and PATH system as required.

Passengers should check with airlines before heading to airports. At the airports, it said it would supply “cots and other essential items ready to accommodate passengers who may become stranded.”

At three Long Island state parks — Jones Beach, Robert Moses and in Montauk — gaps in the dune lines are being filled in to shield buildings and boardwalks, George Gorman, Long Island deputy regional director said in an interview.

Anti-flood preparations at the Department of Transportation include 16 vacuum trucks with sewer jets, five trailer-mounted sewer jets, 12 water pumps and 12 water tankers.

The Fire Island Ferries said it suspended all service on Friday and Saturday but plans to resume carrying passengers on Sunday morning from Bay Shore.

Town of Hempstead Councilman Anthony D’Esposito said by telephone: “We’re making sure our boats and our marinas are tied down.”

Councilman Bruce A. Blakeman asked residents to secure any outside furniture or other items “so there’s nothing lying around that could hurt somebody.” People should also fill up their cars, he said, in the unlikely event of an evacuation.

Oyster Bay Town Supervisor Joseph Saladino recommended that residents have flashlights and batteries, checking that generators are ready — and remove any valuables from places that might flood.

“Residents are advised to use caution if driving as flooding may make travel difficult,” his statement added.

The state Department of Public Service Call Center Helpline can be reached at 800-342-3377.

The Thruway Authority suggested motorists download its free mobile app for real-time traffic and navigation assistance.

Drivers also can check 511NY for road and transit information by calling 511 or by accessing 511ny.org.