Gentler but still unkind, Hurricane Floyd sped up the Atlantic shoreline yesterday, flooding coastal areas and flattening trees in Maryland and Virginia while bringing ordinary life to a halt along much of the Eastern Seaboard.

The once-monstrous hurricane, demoted to a tropical storm late in the day, came ashore early in the morning in North Carolina, then moved into Southeastern Virginia. The brunt of the high winds and heavy rains fell on Tidewater Virginia, Southern Maryland and the Eastern Shore.

Nearly two feet of rain fell in some coastal areas, and winds gusted up to 90 mph in Hampton Roads. Road, rail and air travel were disrupted, hundreds of homes were flooded, and more than half a million customers lost electricity.

But the storm moved quickly to the northeast at about 25 mph, and its most powerful effects were in coastal areas. Forecasters said the storm would race past New York City, through Long Island and just west of Cape Cod, Mass.

Because of Floyd's speed and direction, many communities along the Potomac River that had braced for trouble -- -such as Old Town Alexandria and Georgetown -- suffered no notable flooding or other serious problems. Traffic was light around Washington. With most schools closed and many government workers off, the day became a languid, if damp, holiday for thousands of children and their parents.

In the Washington region, about 457,000 power customers -- most in Maryland -- lost electricity. Prince George's County public schools are closed today because of power outages in 70 of 186 schools, although administrative offices will be open, said schools spokeswoman Jocelyn Harris. Anne Arundel schools also are closed, because of flooded back roads and downed trees.

In the coastal areas of Virginia and Maryland, thousands had to flee their homes, and more than 70 shelters were opened to accommodate them. Scores of main roads in Eastern Virginia and Maryland were blocked by water. Mudslides and fallen trees disrupted Amtrak service for much of the day, and airports were mostly deserted. The storm was blamed for five deaths in Maryland and Virginia. Nearest to Washington, a Fairfax County woman was killed when a falling tree crushed her car.

President Clinton pledged disaster assistance for North Carolina, where four deaths were reported, as well as for Virginia.

Just two days earlier, forecasters had predicted the storm would take a more dangerous course up the center of Virginia to a point just west of Washington.

But Gov. James S. Gilmore III said the damage was bad enough, with nearly 500,000 without power statewide, as much as 20 inches of rain and more than 100 roads in Central and Eastern Virginia closed because of high water. Sections of Interstates 95 and 64 were closed, as were evacuation routes out of Hampton Roads.

In Fairfax, Adrienne Marie Utz, 61, of Centreville, was killed when a 50-foot oak fell on her car about 4 p.m. on Fair Lakes Boulevard near Stringfellow Road.

"It got really windy suddenly and it [the tree] just fell," said Joe D'Agostino, a pizza shop employee who saw the accident. "I turned the car off, and I heard this big boom."

Farther south in Virginia, a 55-year-old Accomack County man died of a heart attack while trying to escape floodwaters, and a 20-year-old woman died when a tree crashed through her mobile home in Halifax County. Another woman died in Hanover County Wednesday night in a storm-related traffic accident on Interstate 95.

The storm also damaged a water pumping station in Portsmouth, depriving some customers in that city as well as the cities of Suffolk and Chesapeake of clean water. The state is shipping 300,000 gallons of bottled water to the area.

In Maryland, in Princess Anne on the Eastern Shore, Ronald Harder, 57, died of a heart attack shortly after midnight after moving emergency-shelter mats at Washington High School, where he had been principal for three years.

Along Maryland's Atlantic coast, violent surf and strong tides continued to eat away at beaches battered by the remnants of Hurricane Dennis two weeks ago.

Many oceanfront businesses and homes, especially in Delaware, boarded up their windows or plastered them with duct tape to keep them from shattering. But there was little, if any, damage from Floyd's winds. Gusts topped out at 50 mph, and up to five inches of rain resulted in minor street flooding in low-lying downtown Ocean City, Md.

In Rehoboth Beach, Del., officials closed their boardwalk for most of the day as the storm surge washed over what little shoreline was left after Dennis. To the south, Dewey Beach also reported minimal damage to its strand. Mayor Bob Frederick said the storm did not breach the town's dune lines, which were constructed last year in a beach replenishment project.

"This had the potential for a one-time knockout blow, but it never materialized," he said. "Because this storm was so fast-moving, it didn't hurt us too bad. With Dennis, it just hung around for five days, pounding away at the beach."

At the northern end of the Chesapeake Bay in Cecil County, Md., the small town of Northeast was severely flooded. State officials reported that most roads were closed and most buildings were inundated. More than 70 people were evacuated to nearby shelters.

Amtrak service between Washington and Philadelphia was suspended after a midday mudslide blocked the tracks north of Baltimore-Washington International Airport. After reviewing for several hours whether the tracks could be cleared of mud and fallen trees, Amtrak officials decided shortly before 5 p.m. to bring stranded trains back to the airport station, where passengers would be housed at a nearby hotel until service could resume, according to John Wolf, a railroad spokesman.

John Dench, who was taking the Metroliner home to New Jersey after a meeting in Washington, said the passengers in his car were in good spirits despite being marooned for more than five hours.

"We're weathering it pretty well. People pretty much have a sense of humor about it," said Dench, one of several riders who contacted Amtrak and reporters on cell phones.

Amtrak's 10 a.m. Metroliner from New York, meanwhile, took eight hours to reach Washington because of the track conditions. A somewhat frustrated female voice came over the train's loudspeaker to announce that the tracks were being cleared. "Please be patient and keep your fingers crossed," she told passengers.

Amtrak officials were unsure when trains would resume normal operations along the Northeast corridor.

The hurricane disrupted travel at the region's three major airports, with airlines reporting scores of cancellations and delays. But most local airports reported light crowds, as many passengers had apparently anticipated cancellations and checked ahead.

The hurricane disrupted long-distance travel along the East Coast, creating delays for trucks and buses using Interstate 95.

In the District, a spokesman for Mayor Anthony A. Williams said police will waive tickets that were issued to cars parked along emergency routes yesterday.

Police announced Wednesday afternoon that cars should not be parked in emergency lanes, and police towed an unknown number of violators, said Ken Snyder, Williams's spokesman. However, tickets cannot be issued until at least Oct. 15 for vehicles parked in emergency routes during a snow or sleet storm, and the D.C. ordinance doesn't mention rainstorms, he said.

"It's only fair that those ticketed aren't held accountable for those tickets," Snyder said, adding that police will send letters to car owners who don't have to pay.

In Fairfax, the relatively light winds spared most of the county from the beating suffered elsewhere. A small number of roads in the county flooded and were closed, and fallen trees blocked a few more. But no major accidents or flooded homes were reported.

The Mason Neck area of eastern Fairfax was the exception. Several trees succumbed to the wind, including one that crashed through the roof of retiring state Sen. Joseph V. Gartlan Jr. (D-Fairfax).

Gartlan and his wife, Fredona, were in a bedroom walk-in closet getting dressed yesterday morning when the 100-foot poplar tree crashed through the roof of their River Drive home and landed in an adjacent bathroom, about a foot away from them. The Gartlans were unhurt.

"This is our dream house, and I've always said there's no way anyone can take me away from this house except in a box," Gartlan said. "Boy, it got pretty close."

The National Hurricane Center in Miami downgraded Floyd to a tropical storm at 5 p.m., when the center was 10 miles south of Atlantic City and top winds were down to 65 mph. In Delaware, two girls playing near a drainage ditch in New Castle County were killed when they were swept into a culvert during the heavy downpours caused by Floyd.

By early today, meteorologists said, the storm is expected to skirt Maine's coast and head out into the North Atlantic. It may still have enough strength to bring bad weather to England in a few days.

"You don't want to say it's a letdown, but you get all geared up to respond, and it's a pretty minimal impact," said Steve Strawderman, battalion chief with Prince William County's fire and rescue department. "I mean, this was less than what a thunderstorm does."

Contributing to The Post's storm coverage were staff writers Hannah Allam, William Branigin, Ruben Castaneda, Patricia Davis, Dan Eggen, Maria Glod, Annie Gowen, Steven Gray, Hamil R. Harris, Dana Hedgpeth, Spencer Hsu, Tom Jackman, Daniel LeDuc, Allan Lengel, Jennifer Lenhart, Eric Lipton, Phuong Ly, Jessie Mangaliman, R.H. Melton, Raja Mishra, Jefferson Morley, Ann O'Hanlon, Peter Pae, Angela Paik, Lisa Rein, Michael E. Ruane, Dale Russakoff, Christina Samuels, Kathy Sawyer, Brigid Schulte, Liz Seymour, Katherine Shaver, Michael D. Shear, Fern Shen, Todd Shields, Alan Sipress, Jackie Spinner, Jamie Stockwell, Marilyn Thompson, Craig Timberg, Marylou Tousignant, Nancy Trejos, Emily Wax, Eric L. Wee, Josh White, Craig Whitlock, Debbi Wilgoren, Scott Wilson, Steve Vogel and Graeme Zielinski.

In the Wake of Floyd

Hurricane Floyd traveled across Virignia early yesterday morning, bringing rain and high winds. Within three hours, Floyd had disappeared north, leaving behind downed tree limbs, power lines and plenty of rain. Here is a summary of conditions as of 4 p.m. yesterday:

POWER

More than 200,000 of Virginia Power's 2 million customers were without power, many in Eastern Virginia. More than 6,000 employees have been mobilized to restore service, which could take up to five days.

Pepco reported more than 70,000 customers without electricity. Affected in Montgomery: 34,000; Prince George's: 29,000; District: 7,000. More than 250 Pepco crews are working to restore power.

Baltimore Gas & Electric reported 150,000 customers without power. Anne Arundel was hit the hardest (72,000).

ROADS

More than 100 roads were closed throughout Eastern and Central Virginia. Most were closed because of high water, but some because of downed power lines or trees.

EVACUATIONS

Mandatory evacuations that took place yesterday:

Virginia counties: Accomack, Gloucester, Lancaster, Mathews, Middlesex, Northampton, Northumberland, Richmond, Westmoreland and York.

Virginia cities: Chesapeake, Hampton, Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach.

Also: Tangier, Hooper, and Chincoteague islands.

RAIN

Rain was most severe in Eastern and Southern Virginia. Some areas had received 10 to 20 inches since Wednesday afternoon.

SOURCES: Virginia Power, Pepco, Baltimore Gas & Electric, Maryland Emergency Management Agency, Virginia Hurricane Preparedness Campaign