Black ice created by freezing rain made for treacherous conditions for motorists and pedestrians in the region Sunday morning, leading to numerous accidents locally and closures of some roads and bridges in New York City, officials said.
Conditions were worse in New York City and Nassau's North Shore, where most of the icy conditions had been reported.
Suffolk Firecom confirmed they sent 12 ambulances to stage in New York City, to be ready to respond to storm and ice related emergencies.
Earlier, the New York Fire Department said emergency calls came in from all around the city on Sunday for weather-related accidents.
Temperatures are now rising into the 40s across the region, as fog, mist and plain rain move in.
Periods of heavy rain were predicted throughout Long Island, totaling about a half-inch, forecasters said.
Earlier, New York State Police reported icy roads along the Northern and Southern state parkways with several crashes.
Nassau and Suffolk police said 911 calls on roads had been higher than on an average normal Sunday -- especially on Nassau's North Shore.
William Floyd Parkway was reopened by noon after a section was closed due to ice.
LIRR officials did not report any delayed trains, but cautioned passengers to look for ice when walking through parking lots or boarding platforms.
"The trains are fine, but getting to the trains is extremely treacherous," MTA spokeswoman Marjorie Anders said early Sunday. "The parking lots and platforms are extremely dangerous. There's not much we can do. It's just an unusual circumstance."
Airport officials at Kennedy and La Guardia were warning travelers to also check their flight status due to potential delays from storms and inclement weather across the Northeast.
Icy roads had forced officials at La Guardia to close the road to the departure level of Terminal B. Passengers were advised to enter the arrival level for all departures at Terminal B.
The New York State Thruway was closed southbound from Newburgh to the New York City line and dozens of accidents were reported on that highway due to icy conditions.
The New York City Port Authority issued several road closures and advisories due to black ice and freezing rain. But as of 11:30 a.m., the Goethals Bridge, Bayonne Bridge, & Outerbridge Crossing have reopened after icy conditions closed bridges in New York City Sunday morning, according to the Port Authority.
The Long Island Expressway, which was closed at the Queens Midtown Tunnel, has reopened.
Nassau County police put out a statement Sunday morning saying, "While all roads are passable, icy roads and sidewalks conditions are causing minor accidents. Motorists and pedestrians are advised to reduce speed and be very careful walking."
The icing that affected Long Island also wreaked havoc throughout the Northeast.
The AP reported that three people died after "flash-freezing" led to a pileup Sunday involving more than 20 cars on Interstate 76, a major interstate outside Philadelphia.
Parts of Interstates 95 and 476 in and around Philadelphia were closed because of icing. The Delaware River Port Authority closed the four bridges linking Philadelphia and New Jersey while workers salted the bridge surfaces.
For the rest of the week on Long Island, Monday and Tuesday are forecast to have sunny skies, but chilly temperatures. Gusty winds and windchill values in the low 20s are expected, with temperatures dipping back into the 20s and 30s.
Meteorologists are predicting a chance of snow arriving Tuesday night and through Wednesday. The winter storm should pass, heading into the weekend, but cold weather and lows in the teens remain in the forecast.