| April 18 April 18,1998 C.Alabama Storm Chase
An outbreak of severe storms and
tornadoes was forecasted for much of Alabama
the morning of April 18. Kathryn Ray and I flew into Birmingham that morning in
anticipation of this outbreak. A strong warm frontal boundary extended from near
Rome Ga to just south of Birmingham to near Meridian Ms. An outflow boundary/
secondary warm front extended east-west from near Laurel Ms to Montgomery Al
to near Columbus Ga. Very unstable air and backed surface winds prevailed over
C.Alabama , particularly in vicinity of the secondary boundary. We watched radar
closely during the morning to see areas where storms fired over and over again.
The area around Tuscaloosa Al appeared to be the "breeding" ground for storm
development, and several storms did become severe by mid-morning. Golfball
sized hail was reported in the city of Birmingham at 10:17am. We disregarded
these storms as tornado producers. The airmass in Birmingham was worked over
from earlier convection so this would reduce the unstable inflow into these storms.
Further south however, deeper unstable air existed and this was the area which
we thought was more conducive for sustaining tornadoes.
We headed out from Birmingham down I-65 to move closer to the target area-the
Clanton /Selma Al area. The boundary remained stationary most of the day and
the airmass was becoming more unstable with time. The winds remained fairly
strong and backed along and south of the boundary-favorable inflow conditions
for tornado development. The area was strongly capped(warm air aloft) but this
was expected to break by late afternoon. An upper level impulse was forecast by
the ETA model to rotate through the Gulf Coast states by evening , and this feature
was expected to provide sufficient mid-level cooling to break the cap. A moderate
risk of severe storms was forecast for much of the state of Alabama and adjacent
states. Tornadoes were mentioned in the outlook, especially in C.Alabama in the
vicinity of the secondary boundary. Brian Stertz was also watching the situation
unfolding from St.Louis and calling frequently with updates.We "camped" out in
Clanton Al for much of the afternoon waiting for the storms to fire.
The first tornadic storms fired over NE Alabama near Anniston and several of the
storms produced brief F0 tornadoes . We decided to wait for hopefully bigger and
better things later. The afternoon passed by quietly in C.Alabama and it was start-
ing to look like just another bust chase or so we thought. Brian Stertz called and
advised us that towers were exploding to our sw over Dallas Co. and that radar
was showing small but increasing storm cells in that area. The cap was breaking!!
We headed out of Jemison towards these storms which rapidly became severe as
they raced n-ne. The low-level shear was tremendous and the storms revealed
supercell structure almost upon development. Tornado warnings were quickly
issued for N.Dallas,E.Perry, and W.Chilton counties as pronounced storm rotation
was now evident on NEXRAD.Before we could reach the storms, tornadoes were
reported in the Marion Jct. and Maplesville area to our west about 10-15 miles. We
could see the dark storm base to the west but haze kept us from seeing the wall
cloud until it was about 5 miles away. We were just south of Clanton when the rotation
approached us quickly from the sw. Vigorous storm rotation could be seen almost half way
up the storm tower. Local residents soon pulled over and watched the storm spin ne. The
storms raced ne as the upper level winds increased with the approach of the mid-level
shortwave. We attempted to keep up with the storms but they were moving at 45-50 mph and
in areas of uncooperative roads. The rest of the evening was a frustrating struggle to
keep up with the warp speed storms. One interesting note was that the area sw of
Clanton (where the first storms fired) proved to be the "breeding" ground for
many of the days more severe storms. This coincided well with the n.edge of the cap and
the position of the secondary warm frontal boundary. Numerous severe storms developed in
this area into the late eve hours and a few tornado warnings were issued.
April 19
April 19,
1998 F-5 Tornado Damage Survey (Oak Grove Alabama)
We decided to call it a day and pulled over to watch the spectacular lightning dis-
play with the storms s and sw of Clanton. We headed back to Birmingham for the
rest of the night. The following morning, we surveyed the Oak Grove Al area where
a F-5 tornado devastated the western section of Jefferson County. The amount of
destruction caused by this tornado was still very evident-even 10 days after the
violent tornado changed the landscape and many peoples lives the evening of
April 8. This tornado was well warned but the intensity level attributed to the un-
fortunate loss of 32 lives that evening. This was certainly the tornado of the year
as far as intensity and human impact are concerned. We photographed damage
in the Oak Grove area where both the school and fire dept were leveled. Here a
few of the photos taken from this devastated community 10 days after the violent
tornado. This was some of worst tornado damage we've seen over 20 years of storm damage
surveying...... The NWS radar and damage reports with photos
documenting the Oak Grove Al F-5 can be
found at the following website:
NWS
Birmingham, AL - April 8, 1998 Central Alabama Tornado Outbreak
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