As the season's first snowfall began to melt yesterday, meteorologists warned that it might have been a dress rehearsal and that the Washington region could see another winter storm before the weekend.

Although it is too early to know, there is a chance that snow will blanket the area again late Thursday and into Friday morning, said National Weather Service meteorologist Brian Guyer as he watched a storm developing along the southeastern coast.

Even if Monday's storm wasn't exactly what area residents expected, it was what meteorologists expected, Guyer said. He said that about six inches fell in Southern Maryland and Charlottesville and that three to five inches coated the D.C. area.

"We weren't taken by surprise," he said, even though Washington weather is notoriously difficult to predict. "We tend to be on the edge of cold air a lot of the time, and so we have the challenge of predicting snow, sleet, rain or freezing rain or a combination of all those."

The storm late Monday is being blamed in the death of a 5-year-old boy who was hit by a car as he rode a sled in Charles County.

But roads, still warm from relatively mild temperatures, presented few problems Monday and yesterday, with few weather-related accidents reported. Most school systems opened on time yesterday or delayed opening by two hours.

Taking no chances, highway officials plowed and dropped tons of salt on the roadways.

District officials said they spread 2,000 tons of salt on city streets. In Maryland, 25,000 to 30,000 tons of salt went down, mostly in Southern Maryland, where some areas got as much as seven or eight inches of snow. State Highway Administration spokesman David Buck said operations continued overnight Monday and ended about 9:30 a.m. yesterday.

Buck said that all things considered, the storm wasn't so bad. "There was an inordinately low amount of crashes relative to a storm," he said. "I was surprised at how few we had."

A Montgomery County school bus carrying 10 students from Briggs Chaney Middle School skidded on wet pavement and slid into a car near Avonshire Lane and Briggs Chaney Road shortly after 9 a.m. The driver of the car, a 48-year-old woman, was taken to Holy Cross Hospital with head and back injuries, authorities said.

Virginia officials said they, too, put tons of salt on roads, but most plows were sent home about 7 p.m. Monday, because there was little to plow.

"No one has a crystal ball to know how much snow will fall, but it is always better to be safe than sorry," said Steven Mason, a spokesman for Alexandria, which plows its own streets.

Yesterday, the federal government, District schools and the school systems of Alexandria and Arlington were open as usual. Schools were closed in Prince William, Culpeper, Stafford, Fauquier and Spotsylvania counties. Other school systems in the region opened two hours late.

In Fairfax County, Dean Tistadt, assistant superintendent for facilities and transportation, was up at 3 a.m. for a conference call with other county officials, regional highway officials and the Weather Service. After he had heard from several former bus drivers that some neighborhood streets had not been plowed and were slick, Tistadt said, he called Superintendent Jack D. Dale with a recommendation: Open school two hours late.

In neighboring Loudoun County, where schools also opened two hours late, Director of Transportation J. Michael Lunsford hit the roads at 4 a.m. to survey the conditions himself. Many years of experience have taught him that the temperature usually drops a bit just before sunrise, he said, freezing wet patches.

Lunsford said that yesterday, no doubt, was only the first of many pre-dawn awakenings he will face this winter.

"I get so tired of watching the weather," he said. "When I retire, I'm not going to watch the weather ever again for the rest of my life."

Staff writers Steven Ginsberg, Allison Klein and Tara Bahrampour contributed to this report.

Horses frolic in a snowy field in Montgomery County. But the snow didn't linger long on Washington area roads this week.

More water is flowing over the Aldie Dam in Loudoun County as snow melts in the aftermath of this week's preview of winter.

Snow adorns seed pods hanging from a sweetgum tree at Eakin Park in Fairfax County.