Update, Friday, Jan. 22: for the latest updates on the New York region.

Winter Storm Jonas is forecast to develop into a major snowstorm Friday through the weekend, potentially blanketing a broad swath of the East Coast in snow, including parts of New York City, Long Island, New York state and Connecticut.

The National Weather Service issued a blizzard watch for New York City and parts of Long Island Thursday.The Weather Channel predicts Winter Storm Jonas will bring between 8 to 12 inches of snow to the New York City metropolitan area over the weekend.Heavy snow and dangerous, damaging winds are possible, with the most-severe impacts forecast for Saturday morning through Sunday afternoon.

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Below, the latest updates on impacts from Jonas for the New York, Long Island and Connecticut area. Stay tuned for the latest updates as they come in.

New York City/Long Island

The National Weather Service issued a blizzard warning for New York City and Long Island lasting from Saturday morning toSunday afternoon.

New York City Mayor Bill de Blasio requested that residents stay indoors when the storm hits. He said at a press conference Thursday morning that there was "no indication at this time that the city's mass transit system will be shut down due to winter storms.” He also did not issue a travel ban, saying more information was needed before that could be in consideration (though alternate side parking will probably be suspended Monday, ). All told, de Blasio advised residents to refrain from any unnecessary travel.

"The bottom line is New Yorkers should be ready for a big storm this weekend,” de Blasio said.

The Port Authority said that air travelers planning on flying out of JFK, LaGuardia or Newark Airports should confirm flight information before arriving. All Saturday afternoon American Airlines flights from New York's three airports will be canceled and are expected to resume Sunday, The Associated Press reported. American Airlines also announced they willahead of the storm.

New York Amtrak service is operating on a modified schedule with some routes canceled over the weekend, including:

Cardinal(New York – Chicago), Train 50 will not operateJan. 23and Train 51 will not operateJan. 22Crescent(New York – New Orleans), Trains 19 & 20, will not operateJan. 22 and 23Palmetto(New York – Savannah, Ga.)Train 89 will not operate and Train 90 will operate between Washington, DC, and New York only onJan. 23Silver Star(New York – Miami), Trains 91 & 92, will only operate between Miami and JacksonvilleJan. 22 and 23Silver Meteor(New York – Miami), Trains 97 & 98, will not operateJan. 22 and 23

The Metropolitan Transportation Authority warned that delays or service suspensions on the Metro North and the Long Island Rail Road are possible.

Events scheduled in New York are being canceled ahead of the storm including Central Park's .

New York State

In addition to the blizzard warning for New York City and Long Island, parts of the state, including Northern Westchester, Orange, Putnam and Rockland counties are under a through Sunday at 1 p.m. local time. Southern Westchester remains under a previously issued warning. At this time, the models show the most-severe snow threats will pass south of the New York area. Still, residents should be prepared for potentially hazardous travel conditions beginning Friday late afternoon.

According to, minimal flight delays and other travel snarls have been reported as the region prepares. Across the region, airlines are offering rebooking free of change fees in advance of the storm. As Jonas ramps up, delays and cancelations are likely to continue. Power outages might become an issue as well.

The state is opening its Emergency Operations Center Friday evening to coordinate storm response. Gov. Andrew Cuomo to take precautions in advance of Jonas.

“This storm could have a significant impact in communities throughout the downstate area — so I am directing all relevant state agencies to be on alert and ready to respond as the weather develops,” he said Thursday in a press release.“We will be closely monitoring storm conditions throughout the weekend, and deploying resources and equipment as necessary. I encourage all New Yorkers in the region to plan ahead, avoid unnecessary travel, and above all — stay safe.”

Connecticut

As of Thursday, there are or warnings for Connecticut in advance of Winter Storm Jonas. Snow showers are currently forecast to hit the state Saturday with accumulations of about 1 inch expected.

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