focus on right movers

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Predicting supercell motion from wind profile data

• (focus on right movers)

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v (m/s)

u (m/s)

• Justification
• nowcasting (just before supercell development)
• helicity is calculated in a storm-relative frame
  of reference
• (helicity determines
  tornado potential)

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• Physical concepts
• advection of the storm by the deep-layer mean
  wind
• interaction of the convective updraft with the
  sheared environment to promote rotation and
  propagation
• (does not account for propagation along
  boundaries, topographic ridges )

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Maddox 1976 30R75
Davies and Johns (1993) storm motion ranges from
30R75 to 20R85, depending on severity
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Colquhoun 1980 inflow equals outflow
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Bunkers, et al. (1998) ID method Based on the
internal dynamics of the supercell (hence called
the ID method) Galilean invariant and
shear-relative
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D7.5 m/s
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Australian supercell environment
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More info

• Predicting supercell motion using hodograph
  techniques (meted)