When regions of contrasting motion are juxtaposed in thunderstorm, there is a good chance that it is a mesocyclone. Such a signature is evident along the NY-PA border in this image. The green and blue shading indicates motion towards the Buffalo radar, while the yellow and orange shading indicates motion away from the radar. This particular mesocyclone was associated with a tornado that affected Smethport, PA and other communities in that area. The velocity field is only part of the story, however.
Meteorologists also examine the intensity and structure of the storm.
Radar is capable of detecting large hail and heavy rain, and these parameters, along with information about the shape of the storm, can be used in conjunction with Doppler velocity data to pinpoint tornadic thunderstorms. Note the classic hook echo in the same location as the velocity couplet in the earlier velocity image. Snapped tree and a downed power line in Warsaw. Row of downed and damaged trees in Warsaw. Christine next to uprooted tree in Warsaw.