A winter storm warning will be in effect at midnight for Long Island, which is now expected to get more snow than had been earlier predicted.
Most of Nassau County, except for along the South Shore, and areas of western Suffolk County -- mostly north of the Long Island Expressway -- are expected to get 8 to 10 inches, with the rest of the Island getting 6 to 8 inches, with lower amounts on the South Fork, according to the National Weather Service.
The storm is poised to strike in the early hours of Thursday through early Friday; the winter storm warning is in effect from midnight through 6 a.m. Friday, the service said.
Still, less than 24 hours before the first of heavy, wet snow is expected, forecasters still were uncertain of the storm's exact track and intensity.
"This is such a tricky forecast," said Brian Ciemnecki, a meteorologist at the service's Upton office.
He said a demarcation line for rain and snow appears to be setting up somewhere between New York City and Nassau County. With the line forming west and temperatures warming, it likely means more rain for Suffolk County, more snow for Nassau.
But "even a distance of 20 miles could be the difference between getting a lot of snow or not much," he said.
The service's snow forecast chart initially showed most of Suffolk getting a total of 2 to 4 inches of snow, with a small western portion of the county getting 4 to 6 inches. Nassau is expected to get 4 to 8 inches.
Snow is expected to begin between 3 and 4 a.m., then turn to rain or a wintry mix at the peak of the Thursday morning commute, he said.
The snow will be heavy and wet, with rates of an inch an hour at the start. As of Wednesday morning's forecast, this first burst of snow is predicted to drop 2 to 4 inches, with higher amounts possible, especially in northern Nassau, said Joe Pollina, also a weather service meteorologist in Upton. Visibility could be one-quarter mile or less at times, he said.
"The Thursday morning commute is going to be a mess," Ciemnecki said.
The rain or wintry mix is expected to switch back to snow, likely after 6 p.m. Thursday, and quickly taper off after 2 a.m. Friday, Pollina said, with snowfall amounts for the second stage still uncertain, but possibly another 2 to 4 inches for Nassau.
Winds are likely to pick up overnight Thursday into Friday, with gusts up to 40 mph, the service said.
If Long Islanders are starting to experience snow fatigue, the reason is clear. As of Tuesday, Long Island MacArthur Airport had seen a total of 35.4 inches of snow since the first of the year, with 9.3 inches the norm for that time period.
Five daily records for snowfall have been broken so far this year -- Jan. 2 with 4.7 inches; Jan. 3, 6.5 inches; Jan. 21, 9.2 inches; Jan. 29, 1.5 inches; Feb. 3, 7 inches.
With this next bout of snowfall, both counties, the Long Island Rail Road and utility companies are preparing for the worst.
Plows and operators are ready to clear roads, authorities said. An additional 32 plows are being deployed to the area from the state Thruway Authority and upstate regions, a state Department of Transportation spokeswoman said. "The region is fully loaded with 30,000 tons of salt," she said.
A spokeswoman for the Long Island Rail Road said that waiting rooms would be open overnight, with added crews coming in early to clear station platforms. Special trains that spray antifreeze on tracks will be on the move overnight, switch heaters in Jamaica will be activated and snow clearing equipment is "fueled and ready to go," she said.
New Yorkers should "prepare properly and avoid unnecessary travel," said Gov. Andrew M. Cuomo Wednesday in a release. If conditions worsen on Thursday, the LIRR may put on extra afternoon trains for those looking to head home early, he said.
Also getting ready is PSEG Long Island, which is continuing to monitor conditions, with a special interest in potential 40 mph gusts forecast for overnight Thursday, a spokeswoman said. All available line crews, tree trimmers and support staff will be available to address issues, with added crews planned to work through the night, she said.The weather service also issued a coastal flood statement, meaning that minor coastal flooding during high tide late Thursday into early Friday is expected. The most susceptible areas will be western Long Island Sound and along the barrier islands, where wave action can lead to minor beach erosion.