Normalized rotation - Columbus tornado
Notes:
Normalized rotation increased simultaneously at the lowest elevation scans prior to tornado touchdown in Columbus, Chenango county. However, it should be noted that this was an odd storm, in that the tornado occurrence appeared to occur several miles southeast of the radar-indicated rotation. Possible explanations for this include a large tilt to the tornado vortex, problems with the radar placement of the rotation due to beam spreading with distance from the radar, and the possibility that the tornado did not occur with the radar indicated rotation, but instead occurred with a very shallow, undetected spin-up along the rear flank downdraft of the storm.
Slide 31