Doppler Radar Observations of Supercell Thunderstorms over
Central Pennsylvania
Ernie Ostuno
Richard H. Grumm
National Weather Service
State College, PA 16801
and
Greg Forbes
The Pennsylvania State University
State College, PA 16801
Characteristics of more than a dozen supercell thunderstorms observed by the State College,
Pennsylvania National Weather Service WSR-88D radar from April 1994 to July 1997 are
presented. Although many of these storms produced tornadoes, downburst wind damage and
large hail, radar data shows that they were typically smaller and weaker than their Great Plains
counterparts.
The terms "non-classic" and "mini-supercell" are used to contrast the Pennsylvania storms from the
larger and more persistent supercell thunderstorms typically associated with strong tornadoes,
which occur in Pennsylvania with much less frequency. The evolution of several non-classic
supercell thunderstorms, as seen on Doppler radar are described. The features associated with
these storms are compared to conceptual models associated with Great Plains supercells.
Details of tornado and downburst wind damage noted on ground surveys are also compared to the
radar signatures of these storms.