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Storm of the Month
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Here's the JULY "firecracker" WINNER that entered northwest Ashley County on the
evening of the 4th. No need for man-made fireworks as this storm was massive
in height with 60+dBz to nearly 40,000 feet located about 120 miles from
the radar. A note of interest was the difference between the cell-based VIL of
81kg/m*m and the grid-based VIL of 61kg/m*m on the 708pm images shown. This
difference is a result of the 124nm cutoff point for the grid-based algorithm
and points out the need for proper technical interpretation when using data such
as this. Grid-based VILs of 75+ and echo tops of 60,000+ feet were accompanied by
baseball-sized hail in Fountain Hill(just left of the storm track) shortly after
the time on our images below.
This storm was a classic supercell that evolved into a bow echo as it crossed
the Mississippi River. At 15,000 feet in the storm, a Rotational Velocity
couplet of >45kts over a 2.0nm radius was detected with a Shear value of
.014units/sec at the time the hail occurred. Unlike most summertime storms,
the forward motion was rather impressive toward the southeast at about 30mph
and winds of 70+mph were reported during the bow echo stage southeast of
Greenville Mississippi.
Reflectivity Vertical Cross Section View
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A 4-Panel View of...0.5Degree Reflectivity(u.left), Echo
Tops (u.right), High Level Layer Reflectivity(l.left), & VILs (l.right)
 Scale:Reflectivity(dBz)
<<-{Note: Elevation of
50+dBz returns- a key in determining hail severity even though base of storm not
known.}
0.54nm Composite Reflectivity View
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