Long Island weather: Heavy rain and gusty winds

Heavy rain and gusty winds were expected to blanket Long Island and much of the region Thursday evening, with temperatures forecast to plunge below freezing by midday Friday.

The monster storm affecting roughly 80% of the country from Montana to Florida to the East Coast is predicted to bring up to 3 inches of rain, possible coastal flooding and potentially even the season's first snowfall.

Plunging temperatures on Friday could create black ice although forecasters predicted it probably will be limited to high ground, including bridges on Long Island.

“The better chance for any … flash freeze would be north and west of New York City and Long Island,” said James Tomasini, a National Weather Service meteorologist in Upton.

Strong wind gusts as high as 55 mph could take down trees and cause power outages, the weather service said.

Long Island’s main utility assured customers it was fully prepared to handle the possibility that those powerful winds will snap branches and trees, downing power lines.

“Heavy winds can increase the possibility of downed wires, which could cause power outages," said Michael Sullivan, vice president of transmission and distribution at PSEG Long Island, "If that happens, our crews are ready to restore electric service safely and as quickly as possible.”

Rain was expected to start falling Thursday evening, reaching a quarter to a half-inch per hour at its peak overnight, with 2½ to 3 inches possible locally during the entirety of the storm, meteorologists said. Widespread coastal flooding is possible in southern Nassau, southwest Suffolk and the South Shore of the North Fork, including Riverhead.

The rain should stop before 5 p.m. Friday, the weather service said. 

Thursday evening, Gov. Kathy Hochul declared a state of emergency for all of New York in advance of the strong weather system.

"With Mother Nature throwing everything she has at us this weekend, I encourage New Yorkers who are considering traveling for the holidays to do so before Friday or after Sunday to stay safe," Hochul said.

Delays for flyers

Even before the rain and heavy winds started locally, the storm was having an effect on air travel during the busy holiday weekend.

Nearly 7,700 flights into and out of the United States were delayed Friday and another 2,300 were canceled, according to FlightAware, a website that tracks flight information.

Local air travelers were not spared the pain.

Kennedy Airport reported 351 delayed flights and another 32 canceled as of 6 p.m. Thursday, according to FlightAware. At LaGuardia Airport, 326 flights were delayed and 97 were canceled, the website reported. At Long Island MacArthur Airport in Ronkonkoma, 16 flights were delayed and another was canceled.

Nearly 4 million passengers will fly into or out of the metropolitan area's three main airports from Friday through Jan. 2, the Port Authority of New York and New Jersey said.

The cold front arriving Friday could send thermometers down to freezing by late in the day, according to Newsday meteorologist Bill Korbel. Temperatures could drop from 55 degrees earlier in the day down to 26 degrees by 6 p.m.

"A 30-degree drop in 12 hours is pretty significant," Korbel said, adding that temperatures are expected to drop into the 20s on Saturday and stay below freezing on Sunday for Christmas Day.

Depending on how quickly temperatures plummet Friday evening, there is potential for a flash freeze and black ice on slushy surfaces, causing dangerous travel conditions, especially on bridges and elevated surfaces, the National Weather Service said. 

A dusting of snow is possible in some spots, likely north and west of New York City, with up to an inch possible in Montauk, the weather service said.

Nassau County and some Suffolk County towns indicated plans to open warming centers this weekend for residents struggling with the plunging temperatures.