Winter came to Washington yesterday in a quiet, steady snow that tested road crews, grounded airplanes and muffled the buzz of the capital city.

Giggles echoed from golf courses and parks, where Flexible Flyers disappeared down hills small and large. Snowball connoisseurs raved about weight and packability. Along city streets and suburban roads, people stopped what they were doing just to watch the slow and pretty dance to earth.

And there were side benefits. Tables opened up at hip downtown restaurants. Those who showed up for work had an excuse for corduroys and sweaters. At the D.C. Department of Motor Vehicles, there was a brief period without a wait.

For the most part, the region's first significant snowfall of the season caused few headaches on streets and highways, thanks to lighter-than-average traffic and well-prepared road crews.

But the gentle snowfall, which measured 3.6 inches at Reagan National Airport and dumped 6 inches on Annapolis, was followed last night by a harsh follow-up punch: high winds and frigid Canadian air. Forecasters said the combination would produce a wind chill of 15 to 20 degrees below zero overnight.

Public schools in Fairfax, Montgomery, Prince George's and Charles counties will open two hours late today, and Anne Arundel County schools will be closed.

Forecasters said the bitter cold will stretch into the weekend. "Even though the sun will be shining by Saturday, it's going to feel really cold," said Andy Pace, a meteorologist with the National Weather Service.

Another snowstorm is expected Sunday, and it could be more potent than yesterday's, he said.

Road crews had barely finished with the job of clearing streets and highways yesterday before they had to reload salt trucks and turn their attention to freezing slush and black ice.

Lucy Caldwell, spokeswoman for the Virginia State Police, said that today "could be the wild day we didn't have" yesterday. "The blowing snow will create very slippery patches and slipping on the ramps. There will undoubtedly be icy patches."

She warned motorists to drive especially slowly and to beware of breakdowns because of the hazard that the extremely low temperatures will pose to marooned commuters.

Advocates for the homeless were out on the streets last night, trying to coax them into shelters. They handed out blankets, coats and socks, as well as hot soup, to those who refused to come indoors.

Yesterday's storm was a seasonal switch from two weeks ago, when temperatures in the 60s broke records and young men in shorts played Frisbee on the Mall.

But just as they had celebrated the weird warm snap, area residents embraced their first good taste of snow.

Jim Shannon, 40, jogged along the Potomac River with snow-covered national monuments as his inspiration. "I wanted to put some spice in my life," said Shannon, an Alexandria resident who wore a blue wool hat and a dark blue jogging suit. "It's calm out here. The perfect day for a run."

Nathalie Sviedrys, a Colombian immigrant in her twenties, bounded out of bed in her Alexandria home at 6:30 a.m. to get her first-ever glimpse of snow.

In a long wool hat that hung down her back, Sviedrys shaped a snowman near the river in Old Town. She planned to take pictures to send to friends in Latin America. "You can't make these things in Colombia," she said, her eyes excited but tearing from the cold.

Pam Leifer, 38, glided around the rolling Brookside Gardens in Montgomery County on her cross-country skis. "It's beautiful. We don't get enough of it," said Leifer, a chef who had the day off.

Although forecasters say the powder was brought to the Washington region courtesy of a cold front, some Leesburg children had a different theory.

"We did the snow dance last night," 11-year-old Michael Patania explained between sledding runs at Leesburg's Meadow Hill. "We put our pajamas on inside out and backward and walked around the house saying, 'Snow, snow, snow.' Our teacher told us to."

For many schoolchildren, the snow day had little to do with snow. America Online Inc. reported a daylong surge in traffic on its youth-oriented sites, as children whiled away the hours chatting with friends online.

Jessica Harvey, 12, of Reston, did squeeze in some snowboarding for more than an hour yesterday morning, but for most of the rest of the day, she was online. Jessica, who has 95 names on her AOL "buddy list," said about seven of her friends did the same.

Others celebrated the absence of crowds in the city. Mike Weiss, who works for the public relations firm Kearns & West, was able to snag a noon table for five people at DC Coast, a trendy K Street restaurant where lunch reservations are typically required two or three days in advance.

But yesterday's weather brought cancellations and open tables, said Boo Kim, the restaurant's general manager.

"It absolutely wouldn't have been possible without the snow," Weiss said.

As the snow fell and school closings danced across television screens yesterday morning, many opted to stay home from work. Federal offices were open, but the liberal leave policy was in effect.

Metrorail carried about 40,000 fewer riders than usual during the morning rush hour, and the light traffic on the roads translated into faster-than-normal commutes for many motorists in the morning and evening.

Jack Breitbeil shaved 10 minutes off his commute between his Alexandria home and Judiciary Square office and was raving about the performance of public works crews and police.

"It was excellent. The roads were clear and the police were everywhere, just making sure there were no problems," he said.

District officials, who were faulted for the gridlock that paralyzed the city during a light snowfall Tuesday, were determined to prevent a repeat.

Patrol officers were dispatched to 100 major intersections and bridge crossings throughout the city during the rush hours to monitor traffic flow.

Although conditions on the ground were good, there were problems in the air.

At National Airport, about one-third of departures were canceled, and all arriving flights were delayed because of poor visibility yesterday morning, according to Tara Hamilton, spokeswoman for the Metropolitan Washington Airports Authority. Flight delays continued until late afternoon. At Dulles International Airport, one-third of the morning departures were delayed, and Baltimore-Washington International airport shut down for two hours.

Air travel out of Washington airports also was hampered by the storm's effect on other East Coast cities.

Travelers at National went from angry to bored and back again as flights were delayed,

canceled, rescheduled and then delayed again.

Ron Ferguson, 45, said that if he heard the loudspeaker announcement to "not accept any suspicious packages from anyone" one more time, he was going to crack. He was trying to get to Kansas City, Mo., but seemed trapped in extended delay.

After consuming several cups of coffee and a salty pretzel the size of his hand, he read the entire newspaper and strolled the "moving walkway" before finding the best possible diversion: the massage chair in one of the airport's retail stores.

Staff writers Dan Eggen, Maria Glod, Annie Gowen, Steven Gray, Raymond McCaffrey, Raja Mishra, Peter Pae, Manuel Perez-Rivas, Michael E. Ruane, Christina A. Samuels, Todd Shields, Alan Sipress and Emily Wax contributed to this report.