Sanborn County, South Dakota tornado on 16 September 2006

Radar reflectivity image from 6:10 pm CDT 16 September 2006.Storm relative motion image from 6:10 pm CDT 16 September 2006

The supercell that produced the tornado near Kimball, South Dakota at 5:12 pm CDT continued to move northeast across Jerauld County and into northern Sanborn County.  The storm became more organized over the next hour.  Hail larger than golf ball size was reported 4 miles southeast of Wessington Springs causing damage to homes and cars.  The radar image above shows a mature supercell moving along the Beadle and Sanborn County line.  While there is some evidence of a bounded weak echo region (BWER) it is difficult to see on this image.  A rear flank downdraft (RFD) is more evident moving across northern Sanborn County.  Damaging winds were associated with this RFD.  There is also a significant circulation along the Beadle and Sanborn County line.  It was in the vicinity of this circulation that an F0 tornado developed in northern Sanborn County.  This tornado was located 15 miles south of Cavour.  No damage was reported with this tornado.  The storm continued to move northeast into Kingsbury County and continued to produce damaging winds and large hail. is the U.S. government's official web portal to all federal, state and local government web resources and services.