Gov. Andrew Cuomo declared a state of emergency for New York City on Thursday as heavy snow and powerful winds battered the five boroughs. The "bomb cyclone" snowstorm is expected to get more intense through the afternoon, Cuomo said at a news conference. Mayor Bill de Blasio declared a winter weather emergency for the city, ordering workers to tow any cars that are blocking snow plows from clearing city streets. "The situation will deteriorate through the day, and the afternoon and evening rush hour we expect will be worse," the governor said. Blizzard-like conditions roiled public transit and grounded hundreds of flights out of the city on Thursday, officials said. The snowstorm is expected to drop up to 10 inches on New York City and bring wind gusts as strong as 50 MPH. Two thirds of all flights out of the region's three major airports have been canceled, said Rick Cotton, the executive director of the Port Authority of New York and New Jersey, at a news conference Thursday morning. That includes 95 percent of all flights from LaGuardia Airport, 70 percent of flights from Newark Liberty Airport and 27 percent of flights from John F. Kennedy Airport, Cotton said. John F. Kennedy put a temporary suspension on all flights about 11 a.m. and LaGuardia flights were suspended around noon. The Port Authority also ended AirTrain service to Kennedy, replacing it with a free shuttle bus. All New York City subway trains and buses are running on a full schedule for Thursday, though there are "sporadic" weather-relayed delays across the transit systems, said Darryl Irick, president of New York City Transit. L train service was suspended between Rockaway Parkway and Livonia Avenue just before 1 p.m. Mechanical and switching problems caused delays on several other lines earlier in the day. The MTA has 2,000 buses equipped with tire chains to handle the slippery, snow-covered roadways, chairman Joe Lhota said. Delays averaging 30 minutes are slamming the entire Long Island Rail Road system. The railroad canceled several trains Thursday morning. New York City Ferry service was suspended at noon. Staten Island Ferry service continued to run on a modified schedule. Schools were closed Thursday but are expected to reopen Friday, de Blasio said. City officials warned New Yorkers to stay indoors and off the roads Thursday, warning of dangerous winds and driving snow. Queens was seeing some blizzard-like conditions as the storm pounded the city with as much as 2 inches of snow every hour early Thursday afternoon, de Blasio said. "This is where New Yorkers have choices to make and I want people to make smart choices – stay inside if you can," de Blasio said at a news conference in Brooklyn Thursday. "If you go out, go out for as little time as possible." The city deployed 1,500 plows and nearly 700 salt spreaders early Thursday morning. Plows have passed every city street, but were struggling to keep pace with the heavy snow, officials said. Arctic air is expected to follow the storm, bringing high temperatures in the teens and wind chills as cold as -20 degrees on Friday and Saturday. Weather that cold makes salt less effective, so plows may not be able to clear roads completely until close to Monday, Sanitation Commissioner Kathryn Garcia said. The NYPD has recorded 86 car accidents in the first four days of the year, down from 135 in the same time last year, an indication drivers were heeding warnings to stay off the streets, Chief of Patrol Terry Monahan said. The storm knocked out heat or hot water at more than 1,400 New York City Housing Authority Apartments, including all 1,300 units at the Woodside Houses in Queens, officials said. NYCHA and National Grid workers are on the scene there trying to fix the boiler problem that caused the outages, a NYCHA spokeswoman said. City workers brought 14 homeless people in off the streets Wednesday night as bone-chilling cold set in, Social Services Commissioner Steven Banks said. Several others were brought inside involuntarily because they were a danger to themselves, Banks said. Officials urged New Yorkers to call 311 to report problems with heat or hot water.