An intense, widespread storm system spawned at least one tornado Friday and battered parts of the Baltimore region with damaging winds and torrential rain, halting flights and flooding roads during rush hour.

The storm ripped through Harford County, doing the most severe damage to a triangular area bordered by Belair Road, Harford Road and Route 152. What witnesses said was a tornado uprooted some trees, sheared off the tops of others, tore down power lines, collapsed two small buildings, sent at least one person to Maryland Shock Trauma Center and brought much of the greater Fallston area to a halt.

"It sounded just like a freight train," said Mary Corun, who lives off Belair Road across from the Fallston Walmart. "We headed right down to the basement."

National Weather Service meteorologist Jim Lee said it appeared likely that a tornado would be confirmed for the Fallston area. As of Friday evening, Lee said the only confirmed tornado touched down at 7:19 p.m. near Baltimore-Washington International Thurgood Marshall Airport. He said the agency would investigate reports of possible tornadoes in Severn, Fort Meade, New Market, Damascus and Hampstead.

"We know there is considerable damage" in Harford County, Lee said. "We think there was a tornado likely."

More than 30,000 Baltimore Gas and Electric Co. customers lost power; more than 13,000 had their service restored by 11 p.m. Rush-hour traffic ground to a halt in many areas, as downed trees, flooded streets and dead traffic lights caused backups. Passengers waited hours for delayed flights at BWI, and thousands of train commuters were delayed when Washington's Union Station lost power about 5 p.m.

Morgan State University student Stanley Hall was traveling on a MARC train from Baltimore to Washington when the train was stuck near New Carrollton for about two hours, he said.

Commuters "were pretty patient for the most part," Hall said, though they vented their frustration as the train approached Washington about 9:30 p.m.

"There were people asking for their money back," he said.

Much of the emergency response focused on Harford County, where the Maryland Emergency Management Agency established a command center; Baltimore City dispatched workers to assist.

Two small buildings were flattened and the busy commercial district of U.S. 1 between Route 152 and Harford Road was dark on what normally would have been a busy Friday evening. A section of Harford Road between Route 152 and U.S. 1 was closed for a short time as fallen trees were cleared from the road. Traffic lights were still out at 8:30 p.m. at some of Harford County's busiest intersections.

"We have two businesses that are completely destroyed," said Harford County spokesman Bob Thomas. He said one vehicle was overturned. Two people were hospitalized, including an employee at an auto reconditioning shop who was injured when a concrete wall collapsed on him, Thomas said.

County Executive David R. Craig visited the scene Friday evening and planned another tour of the debris Saturday morning, Thomas said.

There are no damage estimates, Craig said shortly after 9 p.m. Friday. Craig said the county's building inspectors were ready to assess the damage but wouldn't go to the area until after the tornado alerts were over, which were to remain in effect until 10:30 p.m. or 11 p.m., he said.

"They're here and ready to go," Craig said of the inspectors, speaking by phone from the Emergency Operations Center in Hickory just before he was to travel to the Walmart in Fallston to talk to reporters.

A number of businesses in Fallston were damaged, said Konark Gandhi, owner of Smitty's Fine Wine & Spirits on Bel Air Road.

He saw the wind knock two transformers from utility poles.

"It literally looked like fireworks or something," said Gandhi, whose building was not damaged. "It was pretty scary."

The storm blew down trees and damaged roofs in the area, he said, adding that he saw one building whose roof was completely gone.

At the Fallston Burger King, the doors blew open and the windows started "flexing," said shift supervisor Carrie Stec. A ceiling tile fell in the restaurant's entryway.

The sky was pitch-black, she said.

"In about five minutes' time, it was all over," Stec said.

In Baltimore County, the wind gusts knocked trees over onto five homes in Towson and Lutherville. Most of the storm damage was in the central and northern parts of the county, officials said.

Baltimore City reported flooding in Mount Washington, and Howard County reported a tree fell on a house in East Columbia. Fifteen Howard County officials, including County Executive Ken Ulman, monitored the storm from the county's Emergency Operations Center, said spokeswoman Kathy Sloan-Beard.

The weather in Carroll County caused schools to be dismissed an hour and a half late, and officials there also reported a tree falling on a home. In Finksburg, many businesses lost power, costing owners money on a usually busy Friday night.

Shell station owner Chi Li said his employees ran for cover when high wind gusts came through around 4:30 p.m., knocking out power.

The storm caused similar problems at Belisimos Italian restaurant, which had to close early.

"We would like to stay open, but we don't have anything to serve people," said manager Sean Storm.

The National Weather Service first issued a tornado watch for Western Maryland about 1:30 p.m., and it was quickly extended to the rest of the state. It was the first significant outbreak of severe weather in Maryland during a spring that has been less kind to parts of the Midwest and Tennessee and Ohio valleys. Tornado warnings were reported in central Virginia, Waldorf in Southern Maryland and around the Baltimore area in a flurry of about three hours as the system passed through.

Storm warnings in Maryland continued through 10 p.m. and a tornado watch was issued until 2 a.m. Saturday.

Once meteorologists get reports of damage, they will work with county emergency management officials to survey areas and evaluate whether what looked like a tornado on radar was indeed one, a spokesman said. Those surveys will likely take place Saturday morning.

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