5 JULY NEBRASKA SANDHILLS SUPERCELL
|Mike Hollingshead and I watched some impressive supercells this afternoon from south of Valentine, Nebraska through Brown County to near Brewster and towards Burrell. We kept near the east to west boundary along and near State Road 91 until it was obvious things were going north explosively, then we closed on the storm as it moved from South Dakota into Nebraska. Mike suffered a rouge baseball hailstone from a small storm that erupted in between the Cherry County and Holt County supercells. This small cell grew rapidly and moved north, strangely enough, and though we laughed at its size and gumption (an elevated wall cloud at one point) it dropped a symmetrical, cyclonic shaped fracture on Mike's windshield.|
|At one point, just north of Brewster, we allowed the storm to pass over us when we were convinced it had gusted out and weakened. We'd observed some minor regeneration of the mesocyclone twenty minutes earlier, but as the storm passed our location on State Road 7, it looked relatively innocuous. Just as the forty knot winds and small hail began drove across the road and rocked our vehicles, tones sounded from NOAA for a new tornado warning.|
|After the core passed over, we turned to
see wrapping rain curtains behind us, and a powerful new updraft tower. Later we
learned that the storm had an impressive radar signature at the time, something we would
have normally not happily allowed to sweep over us. Visually, no signs of
tornadogenesis were present. This was a high based storm, and I suspect the rotation
was strictly midlevel.
Both updrafts were visually stunning against the cobalt sky and tall green grass of the sandhills. A beautiful, strange country--though the road network is lacking, the reason we could not intercept the Holt County supercell which reportedly dropped a tornado near Ainsworth.
See Mike Hollingshead's report on this event.