A pre-holiday snowstorm moved quickly through the Northeast on Wednesday, creating hazardous driving conditions and some airport problems on one of the busiest travel days of the year.
Highway traffic was lighter than usual early on the getaway day before Thanksgiving, but travel conditions deteriorated in some areas before an expected improvement later in the day, police said.
Some areas were expected to get from 3 to 6 inches of snow followed by freezing temperatures, assuring a white Thanksgiving.
"We expect that the highways will get worse as the morning progresses and the traffic increases, and that will inhibit the plows and sanders ability to travel up and down," Massachusetts State Police Lt. Paul C. Maloney told United Press International.
He said major highways were generally wet and snow-covered in some areas, but secondary roads were more difficult.
"We've had any number of accidents," Maloney said. "I have no serious injuries (reported), but I'm aware of at least two rollovers this morning."
He said part of the problem was people "failing to adjust to the first snow of the season. They're just not getting their speeds down, they're driving too fast for the road conditions, and a lot of them are sliding off the road and unfortunately into each other."
The snow apparently prompted many people to revise plans to travel to holiday vacation destinations.
"If you can wait until after the storm passes, do so," Maloney advised. "Yesterday we urged anybody that could get out before to do so as well."
Many schools called off classes for the day, giving children an unexpected extra day for the holiday weekend.
Some minor delays were reported at major air facilities in the Northeast, but the situation returned to normal at airports in Pennsylvania, New Jersey and New York after the storm passed.
Delays at Logan International Airport in Boston were due to problems at other airports, spokesman Phil Orlandella said. He said snow crews used 50 pieces of equipment through the night to make sure Logan's runways were clear.
While lines in the terminals were light early, Orlandella said he expected air travel to pick up later in the day.
"I'm not worried," said a young woman waiting for her plane at Logan. "I got here early and my flight doesn't leave until 10."
Amtrak reported regional train departures were nearly sold out, and long lines were reported at the bus terminal at Boston's South Station late Tuesday as travelers sought to beat the storm.
Nationally, Amtrak added 50,000 seats for the holiday, more than half in the busy Northeast Corridor.
Art Kinsman of the American Automobile Association of Southern New England said that many people planning to travel on Wednesday apparently opted to drive early Thanksgiving Day instead because of the weather.
"So hopefully you'll see a staggered holiday drive over the course of the next three days," Kinsman said.
Jeff Larsen of the Boston-area traffic reporting service SmartRoute Systems, had this word of advice: "Leave late, after the storm passes by."
In the West, winds weakened slightly but remained a problem.
In the "Inland Empire" region of southern California, strong winds were noticeably lighter Wednesday morning. The National Weather Service cautioned, however, that winds could be a problem in areas such as San Bernardino, the San Fernando Valley and the mountains east of San Diego.
Gusts up to 55 mph were possible in some of the mountain passes, though the critical Interstate 15 corridor between Los Angeles and Las Vegas shouldn't see significant winds as the usual holiday traffic jam got under way.
Forecasters warned that travel would continue to be difficult at times for motorists in high-profile vehicles and cautioned drivers to keep both hands on the steering wheel and be on the alert for downed tree limbs and power lines.
(Hil Anderson in Los Angeles contributed to this report.)
