ABINGDON, VA., NOV. 9 -- Hundreds of weary firefighters battled forest fires in the rugged Southwest Virginia mountains today, while federal forestry officials hoped that rains sweeping the Southeast would end two weeks of woodland destruction.

The first significant rain many areas have seen in several weeks arrived over a broad swath from Texas to West Virginia, forestry officials said.

The southeastern United States in recent days has suffered the most ferocious autumn fire season in a generation, as at least 350,000 acres have been ravaged in more than 10,500 fires, most of them set by arsonists, officials said.

Smoke from the blazes has drifted up the East Coast, but officials have said the haze does not pose a health hazard. In the Washington region today, smoke was reported as far north as Hagerstown, Md., according to the National Weather Service.

A National Weather Service forecaster in Washington said tonight that rain was falling in West Virginia and was expected to move into Virginia within a few hours.

Rain "has helped us tremendously," said Terry Lewis of the U.S. Forest Service who was posted in Atlanta at a coordinating center for firefighting efforts throughout the Southeast.

Although "we don't have large amounts at this time," he said, the rain has enabled weary firefighters to rest.

Although firefighters were grateful for the cloudbursts -- coming at the end of a two-month period when some areas have received just 11 percent of their ordinary rainfall -- forestry officials cautioned that unless rain falls in larger volume than expected it won't be enough.

Forecasters with the National Weather Service said as much as an inch of rain was expected by overnight across large sections of Arkansas, Mississippi, Alabama and Tennessee, but less than that would likely fall in the smoldering areas of Virginia and West Virginia.

"This doesn't put any of them out," Bill Gillespie, West Virginia forestry director, said of the one-third of an inch of rain expected to fall across the southern end of his state, where 150,000 acres have been scorched in recent days. "It does help to slow them down."

"If it's just a half-inch, in a couple days things will be just as dangerous as they were before," said federal forestry department spokesman Terry Jackson.

Here in the remote coal-mining counties near the Kentucky, West Virginia and Tennessee borders, forestry officials were working to stem numerous blazes in dramatic operations that relied heavily on the work of teen-age volunteers.

"We don't want the hills burning down," said Ashley Cardwell, a student at Patrick Henry High School near Abingdon and a member of a volunteer group called Keep Virginia Green.

"It's really the local people who make it possible," said Chuck Stanley, Virginia's chief of forestry management who came to Abingdon to relieve exhausted local officials. "They're out all day and night."

This volunteer army worked to keep flames at bay on Clinch Mountain, 20 miles northeast of here in Smyth County. Along a ridge atop the mountain, early afternoon gusts kicked up brown smoke and flames that billowed like a volcano eruption above the trees.

Below, six youths in jeans and caps rolled down from under the timber line, tumbling sideways to a grassy flat ridge below. They had hiked the steep mountain with a gas-powered leaf blower and were being sent back to fetch hand rakes.

Halfway up the mountain, classmates were painstakingly carving out a 15-foot-wide fire lane, the only hope for stopping the blazes, which, fueled by dry leaves and high winds, can race up a mountainside. The mountains here are steep, sloping at 45 degrees in most places. Scaling them is treacherous, as a thick bed of leaves makes footing slippery and thin trees are so dry they can break off in a climber's hands.

Fire officials estimated that 65 students from nearby high schools have helped battle the Clinch Mountain blaze. Around the state, several hundred students have taken part in the effort, which has been buoyed by National Guard troops and helicopters.

Chay Fore, 17, rested his dirty face against a branch, exhausted after 27 consecutive hours of work. Only his workmate, 17-year-old George Wright could speak. "It's getting pretty long, and I'm tired," he said.

Another youth, 17-year-old Chad Boardwine, had fought a wildfire two days ago on Walker Mountain, the ridge just south of here. "There were trees burning like chimneys, spitting cinders," Boardwine said. "We pulled our shirts up over our noses to breathe. I guess I was too tired to be worried."

Nearly 150,000 acres in West Virginia have been burned, destroying timber with a value of at least $45 million, state officials said. The toll in some other states included almost 100,000 acres in Kentucky, 27,250 in Tennessee, 28,500 in Mississippi and almost 10,000 in Virginia, including about 3,800 acres since last night.

The death from an apparent heart attack of a volunteer firefighter in Kentucky is the only reported fatality. There have been several injuries reported.