A powerful nor'easter with blinding snow and bitter winds is bearing down on the tri-state, delaying flights, forcing road and school closures, and major reductions in mass transit service.
A state of emergency has been declared in New York and New Jersey in anticipation of the storm that could dump up to 10 inches of snow on parts of the region and cause white-out conditions.
A blizzard warning is in effect for Long Island, and winter storm warnings are in effect for most of the tri-state through Friday morning. A winter storm watch is in effect for central New Jersey and points south.
Get the latest forecast and track the storm with our interactive radar here.
Heavy, steady snow began falling Thursday evening, accompanied by plunging temperatures and whipping winds that will make it feel like 10 degrees below zero in some spots overnight.
New York City, Long Island and areas north and west of the city could see 6 to 10 inches of fluffy snow by Friday morning. Three to 6 inches are expected to fall in central and southern New Jersey.
Check school closings, delays and cancellations here.
The snowfall will combine with winds gusting up to 35 miles per hour to create possible white-out conditions, severely hampering visibility overnight, particularly in areas expected to see more accumulation. Drivers are urged to stay off the roads.
The winds will cause the snow to drift onto roads, and the frigid temperatures will prevent any melting, which could make for dangerously slick roads for Friday's morning commute.
WATCH: Snow at Top of the Rock
The snow is expected to taper off by midday Friday, but the blustery, numbing wind will stick around, causing more localized blowing and drifting of powdery snow through the early afternoon. Temperatures are expected to linger in the mid-teens Friday with wind chills around zero degrees.
The wicked weather means a host of changes throughout the tri-state:
A state of emergency has been declared in New York and New Jersey.
Gov. Cuomo has announced the Long Island Expressway will be shut down at midnight within Nassau and Suffolk, though the Queens section will remain open. Interstate 87 south of Albany will also be closed, and all of Interstate 84 in New York will be shut down. Commercial traffic on I-84 will be banned even earlier, at 5 p.m. The roads will be reopened at 5 a.m. Friday, if conditions allow.
Mayor de Blasio will decide on closing city schools in the morning. After-school programs and class trips are cancelled.
Hundreds of flights have been canceled at New York's three major airports. Amtrak said it will be operating on a modified schedule on Friday.
In New York City, the Department of Transportation announced that alternate-side parking regulations would be suspended as sanitation crews salt and clear the streets. Residents can track snow removal progress in their neighborhood at PlowNYC.
Express subway service in New York City ended early Thursday evening, leaving just local trains running.
The Metro-North and Long Island Rail Road both reduced service Thursday and will run on Saturday schedules on Friday. As a result, there will be no train service on the LIRR's West Hempstead branch or east of Ronkonkoma on the Ronkonkoma branch. Substitute bus service between Ronkonkoma and Greenport will be provided.
Buses will be chained, and extra drivers are being brought in to cover the storm, the MTA says. If roads become impassable, bus service will be suspended. Stay updated on MTA service here.
The state Department of Transportation says it's rolling out plows on major highways and has deployed crews to trouble spots. Officials are looking to avoid a repeat of last February's disaster on the Long Island Expressway, when hundreds of cars got stranded during a quick-moving snowstorm.
The Port Authority says it's deploying extra personnel and equipment to monitor conditions and clear the snow at its airports, bridges, tunnels and PATH stations and tracks.
New Jersey Transit says it will cross-honor all tickets on Thursday and Friday.
After the storm passes, temperatures should rebound slightly Saturday before rising into the 40s Sunday and Monday. By Tuesday, temperatures are expected to plummet again into the high teens.
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Gallery: Your Winter Photos
Photo Credit: Bruce Beck