Near-blizzard conditions and 6 to 10 inches of snow are expected for Suffolk starting early Thursday, forecasters said, with a deep freeze expected across all of Long Island for Friday into early Sunday.
Some parts of Suffolk, which is under a winter storm warning, may see more than a foot of snow, forecasters say.
Nassau County, which is under a winter storm watch, is expected to get 3 to 6 inches of snow on Thursday, News 12 Long Island meteorologist Rich Hoffman said.
"We're preparing for, at least in most areas, more than a half a foot of snow," Hoffman said.
Drivers can expect hazardous conditions for the duration of the storm, the National Weather Service said Tuesday afternoon.
The snow comes courtesy of a coastal storm that also is expected to bring winds gusting between 30 to 40 mph, perhaps as high as 50 mph.
The weather service said the storm will be “followed by potentially dangerous cold” Friday into Saturday, with wind chills well below zero at times.
Forecasters are continuing to eye the storm’s track, given the “typical uncertainty” that comes with such scenarios, said Faye Morrone, a weather service meteorologist based in Upton.
A more western track means higher snowfall and stronger winds for Long Island, while a shift to the east means less.
Tuesday was the eighth-straight day of below-freezing temperatures for Long Island, with highs in the mid-20s but feeling more like the teens in the afternoon, thanks to wind chill, said Jay Engle, a weather service meteorologist also based in Upton.
Wednesday is a contender for Day 9 of the cold spell, with highs near 29 degrees in the forecast with the heaviest snow falling after midnight.
After the storm clears out Thursday night, a “dangerously cold shot of arctic air” takes its place, the weather service said, with sunshine for Long Island but highs during the day Friday and Saturday of 14 and 11 degrees, respectively.
Overnight lows Thursday, Friday and Saturday are expected to dip into the single digits.
“Frigid” with mostly sunny skies “and extreme cold,” Hoffman said.