CHICAGO - Hundreds of holiday travelers spent the night in the nation's second-busiest airport, and some faced the prospect yesterday of doing it again on Christmas Eve as airports across the country recovered from snow and ice storms.

Conditions improved yesterday, but highways were still dangerously slippery in some areas.

More snow fell in the Midwest, where the National Weather Service said up to 4 inches was possible in Chicago. The Northwest faced more snow and sleet, with up to 20 inches possible in the Cascade range in Washington, and icy, wet weather spread over the Northeast.

At least 23 highway deaths had been attributed to the weather, including a woman and her 7-month-old son who died in a two-vehicle crash early yesterday in southeastern Wisconsin.

About 500 travelers had to spend the night at Chicago's O'Hare International Airport after stormy weather forced cancellation of more than 500 flights Tuesday, said Chicago Aviation Department spokeswoman Karen Pride. Some slept on cots, some on the floor or across waiting-room seats, and at least some faced the prospect of spending Christmas Eve at O'Hare.

O'Hare honeymoon

Newlyweds Tommy and Siobhan Costello were at O'Hare yesterday gearing up to spend a second night stranded in an airport hotel en route to their honeymoon in San Diego. They arrived from their native Ireland on Tuesday, but the weather disruptions meant the earliest flight out they could get was today.

"This was supposed to be a pit stop," said Siobhan Costello, 30. "But there's nothing you can do."

At O'Hare's American Airlines terminal, Paul Fustini waited with a bag of food for his daughter Sara, who was trying to get home to Orlando, Fla. Her flight was canceled Tuesday, and she finally got a flight for this afternoon.

"She wishes I would have brought a toothbrush," Fustini said.

More than 100 flights were canceled at O'Hare yesterday, atop more than 500 on Tuesday.

The New York metro area's Kennedy and Newark airports reported arrival delays of up to three hours, the Federal Aviation Administration reported.

"The airlines are dealing with nothing but unhappy customers," said Mike Conway, spokesman for Detroit's Metropolitan Airport, where delays were reported in departures and arrivals because of conditions elsewhere in the country.

The weather service posted winter storm warnings and advisories for large parts of the West, plus parts of the Midwest and the Northeast.

Snow-clogged Oregon

Driving conditions were still tough in Oregon's Portland metro area, where many side streets were clogged with snow. Oregon's largest utility, PGE, said it had restored service to 265,000 customers since the stormy weather arrived last Friday, but 47,000 were still blacked out yesterday.

Across Massachusetts, icy roads caused numerous accidents yesterday morning. Interstate 495 in Middleborough and Wareham was closed because of wrecks.

Despite more snow falling yesterday in the Seattle area, operations at Sea-Tac Airport were back to normal yesterday, spokeswoman Terri-Ann Betancourt said.

She said that the last of thousands of passengers stranded by weekend cancellations were gone by Tuesday and that the only flight cancellations were caused by delays or cancellations at other airports.

"I've lived here 16 years, and this is the first time I've thought, 'I wish it would rain!' " Betancourt said.

The weather service said she could get her wish, at least briefly, with snow showers changing to rain yesterday.

Amtrak also reported improvement yesterday. Trains out of Chicago and elsewhere were leaving on time or relatively close to it.

At least 23 people were killed in crashes on rain- and ice-slickened roads Tuesday and yesterday around the country. Also yesterday, an avalanche in the Rocky Mountains killed two snowmobilers in northern Utah.