Long Island weather: Powerful winter storm likely arrives after midnight Sunday, up to 15 inches of snow possible

An expansive winter storm is expected to dump snow and sleet on a wide swatch of the country before approaching Long Island Sunday, where forecasters said up to 15 inches of snow is possible.

The National Weather Service said the storm should arrive just after midnight early Sunday and bring about 1 to 2 inches of snow by daybreak. But weather service meteorologist James Tomasini said much more will be coming through the day and into Monday. And a later weather service advisory Thursday also warned of "near whiteout conditions" for Sunday.

 "Looking at it as one single event, we could see 14 to 15 inches on Long Island," he said.

Before it arrives, the storm is expected to bring various forms of precipitation to large portions of the country, moving east from Rockies, through the Great Plains, the South, and then up north to New England. 

It's one of the larger storms to impact the tristate in recent years, Tomasini said, with the massive snowfall triggered by the mixture of heavy moisture with an arctic air mass over Long Island.

NewsdayTV Meteorologist Bill Korbel said Thursday that the sprawling storm will affect much of the country, causing massive travel problems.

"It’s living up to expectations," Korbel said. "This thing is huge. By Sunday morning two thirds of the nation may be affected one way or the other by this incredible weather system, either from extreme cold or snow on Long Island."

"It’s going to be a mess in many ways,” Korbel said. "It’s going to be a problem and by Monday morning, you’re probably not going to go anywhere," he said.

Gov. Kathy Hochul warned New Yorkers they should expect "an extreme weather event the likes of which we haven't seen in years ... this is one you need to take very seriously."

But the weather service also cautioned that the storm's path could change and that sleet and freezing rain could mix with the snow Sunday night closer to the coast, which could cause some reduced accumulation. 

The storm will be accompanied by a prolonged period of frigid air, sending the tristate area into a deep freeze beginning Friday night and lasting into the middle of next week.

The weather service issued a cold weather advisory from 10 p.m. Friday through 10 a.m. Saturday, with minimum wind chills of -5 below zero. The cold can lead to frostbite and hypothermia if bare skin is exposed for long periods of time, the advisory warned. 

Friday with see a high in the mid-30s, then fall back to the single digits in many places. Saturday will be the coldest day of the week, with highs in the mid-to-upper teens, and lows around 11. The mercury moderates slightly for Sunday, with a high of 28 and a low of 21.

"The cold air sticks around Saturday, which could be one of the coldest days in the past several years with highs forecast in upper teens and some records are in jeopardy," Tomasini said. "The cold air will linger after the storm into next week and it’s going to be very cold. There could be several days in the 20 and lows in the single digits."

Winds are not expected to produce blizzard conditions, but they will come into play Friday, when they are predicted to gust up to 32 mph, adding to the extreme cold. Saturday they are expected to gust up to 20 mph, before calming down at night. 

By John Asbury

john.asbury@newsday.comJohnAsbury

John Asbury is a breaking news and general assignment reporter. He has been with Newsday since 2014 and previously worked at The Press-Enterprise in Riverside, California.