June 9, 2003 - Stuart, NE - O'Neil, NE - Tornado - Supercell
 

A big day up in northern Nebraska, Holt County. Several tornadoes, including a few weak spin-ups, a nice milky white elephant trunk, and then a large dusty tornado. I'm still cleaning the sand out of the truck. (they don't call this area the Sandhills for nothing)
 
Chase Account by: Jonathan Garner
 
Brian Thalken, Mandy Aronson, and myself left Lincoln at 12:40pm today, with a target around Bassett, NE. After passing through Burwell, we observed towers developing to our west and northwest...we checked radar/satellite/surface data, and saw that a cell was beginning to develop in Keya Paha County Nebraska...so we ignored the towers to our west and continued north to Bassett. The cell to our north rapidly developed into a classic supercell (both visually and on radar) as we approached it from the south. At 5:05pm, we drove a few miles east/northeast of Bassett in order to get a better viewing angle of the base and updraft (a large, circular anvil was present above the cylindrical updraft tower). The rain-free base continued to widen, and took on a circular, bowl shaped appearance at 5:40pm. Then, weak rotation was observed at the base, with a clear slot starting to "cut" into the updraft...a rotating column/tube of dust was observed under the rotating base at 6:01pm. We decided to drive further northeast in order to keep up with the base of the storm, observing several more weak tornadoes during this time. By 6:40pm, a new, more well-defined wall cloud developed, and we approached it from the west. The circulation was very strong within this wall cloud, and appeared to be tightening up into a tornado, but it couldn't manage to produce (we were about 1/4th mile west of this wall cloud...would have been great video if it produced a tornado).
At 7pm, we repositioned back to the southeast, and then headed east on highway 20. As we approached Stuart, NE, a new area of rotation under the base of the supercell developed, and soon led to a large funnel at 7:03pm. We headed north through Stuart toward the low-level mesocyclone, and at 7:06pm, the funnel became more vertical and reached the ground. The tornado widened a bit into an "elephant trunk"...it took on a ghostly-white color and we could observe the entire parent updraft column above the tornado...very photogenic. This tornado moved east a mile or two, and then dissipated at 7:15pm. We then made our way toward Atkinson, NE...during this time, the supercell developed another low-level mesocyclone...we went east through Atkinson at 7:30pm, and again approached the new wall cloud from the west. The rear-flank downdraft was extremely strong, and we could observe violent rotation at the base of the storm 1-2 miles immediately east of our location...another tornado had formed, sucking up huge amounts of dust in front of us. We kept moving east behind the tornado, and the RFD continued to strengthen, with gustnadoes forming from time to time...eventually, we couldn't go any further east because the RFD winds began to knock trees down into the road. From here, we made our way east toward O'Neill, NE, traveling next to the clear-slot the whole time. Scud bombs erupted several times under the flanking line, with shear funnels forming and dissipating occasionally. We decided to call off the chase once we reached O'Neill, since it was impossible to get to the other side of the storm (we would of had to driven underneath the rotating base...which would have been a foolish thing to do).