UPDATE: Tornado Warning In Bucks, Montco

UPDATE: The previously issued tornado watch has been upgraded to a warning in portions of Bucks and Montgomery counties. The tornado warning goes until 4:30 p.m. in the following towns: Lansdale, Doylestown, Byram, Chalfont, Tinicum, New Hope,Pipersville, Gardenville, Lumberville, Lambertville, New Britain,Brittany Farms-Highlands and Montgomeryville.

Just before 4 p.m., a severe thunderstorm capable of producing a tornado was located over Lansdale about 17 miles north of Philadelphia. It is moving northeast at 50 mph.

Pea-sized hail is also possible.

The National Weather Service says: "Flying debris will be dangerous to those caught without shelter. Mobile homes will be damaged or destroyed. Damage to roofs, windows, and vehicles will occur. Tree damage is likely."

Residents are advised to take cover, and move to a basement or an interior room on the lowest floor of a sturdy building.

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PHILADELPHIA, PA — A tornado watch has been issued across the Philadelphia region, according to the National Weather Service.

The watch will remain in effect until 7 p.m. on Monday.

A tornado watch means conditions are favorable for the development of a tornado.

These counties are under a tornado watch: Bucks, Chester, Delaware, Montgomery and Philadelphia.

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