May 16, 2004 - Central Nebraska

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Chase Account by: Jonathan Garner
 
Brian and myself targeted an area between Kearney and McCook today. After reaching Lexington, NE, we decided to head southwest down highway 283 toward the McCook area. At 3:30pm, we soon spotted a rapidly developing thunderstorm which had a solid forward flank precip core. We passed through the core, which was putting out small hail, and almost immediately after we reached the base, a tornado warning was issued for this cell by the NWS. We observed a large rain free base which appeared to be very agitated, however, it was also slightly elevated, and didn't appear to pose any tornado threat. Still, we decided to follow the cell northeast, as the base went through a bit of re-organization. After reaching Lexington once again, we headed east down I-80 in order to reposition with respect to the RFB. The storm was given a third tornado warning as we did this. We then went north from Overton, NE and entered the Sandhills. After parking on top of a hill, we got excellent video of a new wall cloud 3 miles to our southwest which was rapidly ingesting scud from the rain core. This wall cloud moved almost over us, with the base of wall cloud literally boiling with agitation. Rotation was also observed, but tornadogenesis was still not immanent.  
At 5:50pm, the storm was now moving through Miller, NE. The tornado warning was dropped for the storm, and it appeared as if it were weakening. We then made the fateful choice of letting the storm move off to the northeast while we drove southeast toward Kearney. We decided to take a chance and move east down I-80 in order to reassess the severe potential of this storm to our north, or else drive on home. A new tornado warning was issued for the storm as we were driving east from Kearney, and the storm produced a few brief tornadoes during the next 45 minutes. We decided to drive north from Grand Island and intercept the storm once again as it moved east through Howard County. The structure had rapidly improved as we were doing this...it was obvious that this cell had evolved into a strong supercell. At 7:15pm, we were close enough to see the base, with rapid, broad scale rotation observed. It was very dark underneath the wall cloud, so it was impossible to tell exactly what was happening. We followed the supercell northeast into Merrick and Nance Counties as the storm went through an occlusion, but the tornado window had once again closed on us...it was just bad luck that we let the storm go at the wrong time.