A winter storm blanketed much of the Northeast on Friday, delaying flights at the region's major airports and causing havoc during the morning commute.

The massive system, which had brought everything from freezing rain to sleet to snow in parts of Kentucky, Missouri and Illinois on Thursday, lumbered eastward and northward overnight.

The weather service predicted 6 to 9 inches for New York City, where snow began before dawn. Up to a foot was forecast in suburban counties, 10 inches in Connecticut. Storm warnings extended northward across Massachusetts and southern New Hampshire. In many places, snow was changing over to rain, sometimes freezing rain.

"Already, this is the most significant storm of the season for New York City," said National Weather Service meteorologist Jim Connolly.

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Flights at John F. Kennedy International Airport and Newark International Airport were delayed more than five hours, and in Philadelphia the average arriving flight was 4 1/2 hours late. Some airlines waived their fee for passengers rebooking tickets.

Driving was no more fun than flying. The speed limit along the New Jersey Turnpike was reduced to 35 mph, and jackknifed rigs shut down southbound lanes of Interstate 95 for a couple of hours in Greenwich, Conn.

"I didn't go over 30 mph on the expressway," said Paul May, whose commute on New York's Long Island on Friday took three times as much as normal. "It's very slippery. The roads are treacherous."

Four hours into his route delivering Coca-Cola to Manhattan stores, Anthony Grady unloaded several bottles in front of a convenience store and said, "Normally I would have finished this route in five hours. Now it might take me 10."

The weather was tough on horses, too, so the race card at Aqueduct was canceled.

In the New York suburb of Pelham, though, grandmother Margaret Sisto welcomed the change in routine. Since her daughter was staying home from work, she had the day off from taking care of her granddaughters, ages 1 and 2.

"I got a snow day," she said as she shoveled her front walk.

Up to 10 inches of snow was possible in parts of Connecticut. Romeo Simeone, who owns a market in New Haven, Conn., said there had been a run on bread, eggs and other staples a day earlier, but the market was still plenty busy Friday with people ducking in for coffee and sandwiches.

"We got to accept a little weather. It's a little uncomfortable, but look at the beauty of it," he said. "Everybody is smiling, everybody is happy, especially the kids."

Before moving into the Northeast, the storm dropped up to 4 inches of snow on parts of southwest and central Ohio. Several lanes of a highway in Sharonville, near Cincinnati, were blocked after a vehicle slid under a propane truck.

Throughout the Dayton area, residents and municipalities were worried about salt supplies.

"We have a minimal supply of salt left in the barn," West Carrollton service department director Rich Norton said. "We need to make this last until we can get a new supply."

In Missouri, where the problem was mostly ice rather than snow, the State Highway Patrol cited slippery roads as factors in accidents that killed five people Thursday and early Friday.