Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, August 18, 1994 TAG: 9408180123
SECTION: VIRGINIA PAGE: A-9 EDITION: METRO
SOURCE: By LISA APPLEGATE STAFF WRITER
DATELINE: LENGTH: Short
And the intense blowing from the remnants of Tropical Storm Beryl spawned at least eight tornadoes in North Carolina and Virginia in a 12-hour period Tuesday night and Wednesday morning.
How could something that causes such a wrath of rain and flood also create destructive winds?
It's all in the cyclonic turning, says Donato Cacciapaglia of the National Weather Service station in Roanoke.
Imagine the counter-clockwise spiral formed by water running down a bathtub drain. Both tornadoes and tropical storms have a similar type of spiral in their centers.
But tropical storms also have expanding bands of wind that stretch out from the middle. Those active winds, especially in the northeast section where they are the strongest, reach out and spin around into tornadoes.
"Tropical storms probably bring the greatest threat for this region of the country," Cacciapaglia said.
The Blue Ridge Mountains usually break up tornadoes, but because tropical storms follow the mountains' edge, they are more likely to produce destructive twisters.
Beryl formed Sunday over the Gulf of Mexico, about 200 miles south of Panama City, Fla. By Wednesday night, it had dwindled to a tropical depression, with most of its rain falling on Pennsylvania and New York.
by CNB