Heavy rain and high winds hit Long Island with full force overnight, just a hint of what a powerful nor’easter could bring by Tuesday afternoon, including snow and moderate flooding.

As of about 12:45 a.m. Tuesday, the temperature was hovering in the low 40s. Forecasters say there's a better-than-average chance the rain will turn to snow Tuesday, continuing with a mix of rain through early Wednesday.

Upstate is expecting a foot or more of heavy, wet snow — the kind that causes widespread power outages. No major outages were showing up early Tuesday on PSEG Long Island's website.

The nor'easter's first phase overnight will bring a total of two inches or more of rainfall, forecasters said. The most intense rain was expected to continue through to 10 a.m. Tuesday.

The precipitation was then due to change to snow Tuesday afternoon when temperatures get close to freezing, with one to two inches expected, and it could continue snowing through Wednesday morning. But no blizzard is expected.

"Confidence is increasing that although rain will change to snow for the NYC/NJ metro and coastal surroundings early tomorrow AM, the heaviest snow banding will remain to the north," the weather service said in its Monday night storm advisory.

Winds will build through the storm; between 20 mph to 30 mph sustained winds overnight into Tuesday with 40 mph gusts, increasing to 25 to 35 mph sustained winds Tuesday night into Wednesday, with possible gusts up to 50 mph — and up to 60 mph for the East End. The weather service has issued a wind advisory for Suffolk for late Tuesday into Wednesday.

Meanwhile, upstate could be hit with a foot or more of snow, prompting Gov. Kathy Hochul to declare a state of emergency Monday for upstate counties and warn New Yorkers there, in a briefing in upstate Latham, that they should expect an "epic event" with "widespread outages." 

"There's no reason in the world to have plans to go out tomorrow," she said, urging New Yorkers to stock up on batteries, gas, groceries and other essentials. 

"Light snowfall is expected later this morning into the early afternoon that will pick up tonight," Hochul said Monday. "New York City and Long Island," she said, may get "a couple of inches," and that is where "we also are watching for coastal flooding."

With the rain, and strong winds, Long Island is still at risk for outages, forecasters said. 

Dave Radell, a meteorologist at the weather service’s Upton station said: “We’re anticipating a full 24 hours of some pretty strong winds associated with this system.”

PSEG and mass transit officials said they were preparing for the storm.

Michael Sullivan, vice president of Transmission and Distribution at PSEG Long Island. “We have performed system and logistic checks, and have a full complement of personnel who can jump into storm mode if needed." ”

The weather service issued a coastal flood advisory for northeast Suffolk and southern Nassau through Tuesday, warning of minor to moderate flooding in low-lying vulnerable waterfront areas, especially during high tides. 

— With Nicholas Spangler and John Asbury

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