Danville
(F1) [ Back to Top
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This particular tornado was spawned by a supercell thunderstorm
that initially produced extensive damage in the Haleyville area
around 1005 CDT. In addition, this same supercell would eventually
move across the Huntsville metro area producing a brief F0 tornado
near the Greenbrier exit of Interstate 565, measured wind gusts
to near 60 MPH on Redstone Arsenal, and drop huge amounts of damaging
hail across the southern part of the city.
One of the interesting things about the Danville tornado is that
it formed not in the classic hook echo region of the storm, but
in what is commonly referred to as the cyclonic bookend vortex or
“comma head” portion of the storm. This tornado initially produced
maximum estimated wind speeds of 90 miles an hour and demolished
a large barn. The width of the tornado at this point was at 100
yards. The tornado weakened to F0 intensity with maximum estimated
winds at 70 miles an hour as it approached Danville. The tornado
moved east and northeast through Danville, producing slight damage
to the Danville High School gymnasium roof, the roof of the press
box at the football field, and to the back stop and outfield walls
at the high school baseball field.
The intensity of the tornado increased to F1 just east of Danville
High School as it uprooted a few large trees and lightly damaged
some roofs and awnings of around five homes. Maximum estimated winds
of the tornado at this point were 80 miles an hour. The tornado
continued east to Craze Road, about a mile east of Danville, where
estimated maximum winds increased to 90 miles an hour. At least
four homes suffered minor roof and awning damage, and a barn was
destroyed on Craze Road. The width of the tornado at this point
increased to 150 yards before it rapidly dissipated 300 yards east
northeast of Craze Road. The path length of the tornado was at least
five miles.
A tornado warning had been issued for Lawrence County at 1001 PM
CDT. A tornado warning was issued for Morgan County at 1026 PM CDT.

Radar reflectivity image of the storm that produced the F1 tornado
near Danville. The tornado actually occurred in the “comma head”
region of the storm.

The Storm Relative Motion (SRM) image from KHTX radar showing
the velocity couplet near the time of the tornado touchdown in Danville.
Note: the bright orange and pink colors are bad velocity values
known as “dealiased data”.

Barn destroyed 2 miles northeast of Danville.

Damage near Danville.
Decatur
(F0) [ Back to
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A separate tornado that occurred earlier Friday evening, east of Decatur,
Alabama, was determined to have F0 intensity. This tornado touched
down along highway 20, about two miles east of Decatur and sporadically
produced very light tree damage until it reached the Madison-Morgan
county line. A large billboard along Interstate 65 also suffered damage
as the tornado approached Madison County. The maximum estimated winds
with this tornado were 70 miles an hour. The path width of the tornado
was 50 yards.
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