The Washington area felt the wet slap of Hurricane Gloria yesterday as heavy rains and high winds closed schools, disrupted air and ground travel and interrupted electricity to about 9,000 homes and businesses.

Most emergency officials had expected that the storm's impact would be much worse.

"We were prepared for a disaster: six to eignt inches of rain and sustained winds of up to 50 miles an hour," said Joseph Yeldell, director of the Office of Emergency Preparedness for the District. "But we got only about three inches and winds were very light."

"Believe it or not, there were no storm-related incidents reported to Fairfax County police overnight," said a police spokeswoman there. Nor were there any reported injuries or major damage elsewhere the region.

The heaviest damage apparently occurred at the Canterbury School in Accokeek, where a basement wall buckled because of rising ground water, causing a roof to collapse onto three classrooms. The school was closed and damage was estimated at $200,000.

Motorists were snarled in early morning traffic caused by flooding and many morning airline flights were canceled.

But thousands of school children got an unexpected holiday with the closing of area schools, including those in the District, where there is a tradition of keeping the schools open no matter how severe the weather. Only Arlington and Alexandria kept their schools open.

"We do have a history of never closing," said Janice Cromer, director of communications for the District's 186 schools. "The radio stations could hardly believe it when I called to announce our closing."

Cromer said that officials made the decision at 5:30 a.m. "We knew the storm would be gone by 11:30 a.m., but we were concerned that it was going to hit between 7 and 9 a.m., when students would be going to school," she said.

In Arlington, the attitude was different. "We questioned the police and fire officials and they said they didn't feel there was any danger of flooding in our area," said Margaret Heckard, a spokeswoman for the county schools. "We opened and it didn't seem any worse than any other storm with a lot of rain."

Not only did the heavy rains close National Airport, but some airlines reported that their computers, normally used for booking flights, were inoperable because of difficulties with telephone lines to the Northeast.

The airport reopened yesterday afternoon and flights resumed, but officials said it may be days before service is back to normal.

Flooding closed some key roads, resulting in massive traffic jams during the morning rush hour. One of the biggest tie-ups occurred at the 14th Street bridge after park police closed the northbound and southbound lanes of the George Washington Parkway at 6:30 a.m.

Flooding was also reported in some homes. Lawrence Wright awoke yesterday and found about two inches of water on the floor of his Oxon Hill Village apartment. "My son got up after 5 to deliver papers and it was flooded then," said Wright, while standing under a ceiling spotted with water marks.

Power outages hit 2,100 customers in South Arlington, including four schools; 1,300 customers in Northwest Washington; 1,000 in Falls Church, and 700 in Southeast Washington. The other 3,900 customers who lost power were scattered through the metropolitan area.

The electricity went off three times at National Airport, according to Virginia Power, which serves most of Northern Virginia. A company spokesman said there were two half-hour outages during the morning and one 10-minute outage in the afternoon.