July 31, 1983 David Hoadley, Editor 3415 Slade Court Fairfax

July 31, 1983
David Hoadley, Editor
3415 Slade Court
Fairfax, Virginia
STORM-TRACK
$3.20/year
Vol. 6, No. 5
Bi-monthly
(Checks payable to
David Hoadley)
I. COMMENTARY
Storm Chase '83 is now over for most of us. Contrary to the expectations for a very active tornado
spring, April and May were comparatively quiet through the central plains, with a few notable exceptions
such as the Houston area storms. Chasers seemed to take turns as different systems presented themselves.
Several cars of Norman chasers, with Lou Wicker, joined up with the Editor in photographing at least
three May 13 tornadoes from Estelline, Texas to Vinson, Oklahoma (See ST, Vol. 6, No. 5); Jim Leonard
and Barbara White just missed these vortices but "aced" two high contrast twisters on May 17 south of
Medicine Lodge, Kansas, while the Editor was pursuing a wall cloud northeast of there; and on May 20,
Tim Marshall and Roy Britt were all over a multi-tornadic storm near and northeast of Plainview, Texas,
which everyone else missed while working storms further east. Something for everyone! Nonetheless, a few
considered mid-May as a somewhat spartan period, and Jim Leonard said that he felt lucky to have taken
what pictures he did. However, the season picked up again in June (Gene Moore photographed several in
Kansas) and may still yield a substantial number of tornadoes for the year.
- - In reviewing some old notes from Tim Marshall on the mile wide tornado near Pampa on May 19, 1982, I
came across an interesting observation. One damage report was received on a frame building in its path,
which only lost, a roof and part of a wall rather than being virtually flattened as might be expected.
In other words, the size of this tornado was not coincident with its severity. Our discussion at that
time led to the thesis that there may be a maximum threshold of vortex diameter, beyond which average
wind speeds do not continue increasing, but begin to decrease, or where suction vortices become less
likely.
Studies may indicate a bell shaped curve that
shows increasing winds for tornadoes up to a
half mile wide but decreasing winds thereafter,
with increasing swirl diameters. In short, the
monster vortex may only be an anemic windbag.
- - Keith Brewster responded to the last Commentary Section in ST. "... you may have heard of a recently
released Dept. of Commerce report, which states that eventually all observations could be made automated
or remotely sensed, and that the primary purpose of the National Weather Service should be severe
weather warning and general public forecasting. An obvious contradiction -- any severe weather
forecaster knows the importance of seemingly insignificant remarks such as TCU W, FEW CU and of courseCB DSIPTD! Of course, don't expect your congressman to recognize this."
II. ROSTER
III. LETTERS/PHONE CALLS TO THE EDITOR
On May 20, 1983, Tim Marshall and Roy Britt had an easy chase from their Lubbock, Texas base station to
an early afternoon tornadic storm near Plainview, only an hour's drive away. They watched this storm
cell develop for over an hour, before the first tornado appeared at 3:18 PM CDT.
For the next 27 minutes and ten miles, they
followed it, mainly as a concentrated dust swirl
on the ground with occasional suction vortices
but little indication of a cloud base
condensation funnel. Eleven minutes later they
drove under a rotating wall cloud and just
missed being swept up by a 1/3 mile wide tornado
that dropped down on the road behind them.
*On May 24, Roy and Tim caught up to a severe storm near Silverton, Texas, with a banded base similar to
the Garden City storm of May 30, 1978 (ST: Vol. 5, No. 2). A small funnel was photographed and 80 MPH
winds were encountered.
In fact, the blowing dust was so thick that the pavement
disappeared, and Roy ran off the road,-- albeit at very low
speed. It was then that Tim said, "Here! Let me drive. I can
get us out of this!" Whereupon he opened the door and the car
was instantly filled with blinding, storm driven Texas turf.
When at last, they arrived in Lubbock, grit and dust coated
cameras, lenses and everything else -- and each chaser looked
more like a ghost than a person.
*Keith Brewster recounts: "The world's largest 'bust' occurred in southwest Oklahoma, May 17, 1983. As
you may have heard, this chase featured a caravan of 11 vehicles and 32 people, not counting two
vehicles from Oklahoma University (TOTO crew , who were within radio range as this group watched a
highly sheared (though very slowly rotating) CB develop on a dry-line near Willow, Oklahoma. Although
some severe weather was encountered later by many of the group further north ..., I couldn't decide if
the highlight of the chase was catching a glimpse of Bill of 'Bill's Safety Cab' in Chickasha, or seeing
Don 'DbZ' Burgess standing on the hood of a car to get a measurement with the hand-held anemometer (of
the 850 mb jet????), as passers-by from the metropolis of Duke, Oklahoma stared at the crowd! By the
way, don't believe Don if he tells you the vehicle was hit by tennis-shoe size hail!"
Keith also adds an open inquiry "...I and others here at OU are interested in seeing something on
hurricane chasing. What kind of strategy is employed, etc." (How about, it, hurricane chasers? How do
you plan differently for hurricanes, as compared to tornadoes? What different risks do you encounter
(flooding, blocked roads, etc.)? What's the best, vehicle to use? -Editor)
VI. BULLETIN BOARD/COMMERCIAL MARKET -$- FOR PICTURES
V. CAMERA TIPS
VI. TRAVEL TIPS
FUNNEL FUNNIES: Headed Off at the Pass (Fiction)
VII. FEATURE #1
Annual Storm Barbecue
On Sunday, May 15, seventeen tornado chasers showed up at a local Norman apartment for the Annual STORM
(Storm Trackers of Oklahoma Ribaldry and Mendacity) barbecue, to eat, drink, swap stories and show storm
pictures. As mentioned in the last ST, Barbara White and Jim Leonard were present, showing
video tapes of the May 13 Estelline supercell and of the
at the shaky initial footage for the May 17 storm, taken
partially rain soaked from an earlier encounter, and the
considerably. However, it added a nice human touch to an
excellent photography.
May 17 Medicine Lodge tornadoes. Jim apologized
while standing next to the car, since he was
strong inflow wind was chilling him
otherwise very professional showing and
Among several interesting experiences that were told:
- An account of a St. Elmo's fire electrical/corona discharge in advance of the Blackwell, Oklahoma
tornado. It happened ahead of the wall cloud but underneath the anvil, appearing as a blue-green
discharge "rippling" back and forth across the ground like a "carpet of fire."
- A Gene Moore account of a rarely heard pulsing, thunder sound, starting as a low "thump" and
increasing steadily but rapidly to a constant thunder-like roar. Heard for 7-8 minutes northeast of the
May 12, 1983 Enid storm, his perception was that the sound proceeded as if from a giant megaphone,
pointing at him, and that if he had moved 10 miles in any direction he would have left it. He and Eric
Rasmussen were speculating on possible causes, ranging from a pulsing type of lightning to some kind of
wind-shear induced shock waves. The lightning proposition sounded similar to a remarkable night-time
electrical display which the Editor witnessed from Bismarck in southeastern North Dakota on July 5,
1962. From the center of a large, back-sheared Cb and midway between anvil and cloud base was a rapidly
pulsing, very bright electrical discharge, flashing about four times each second and constantly for
several minutes. It appeared to come from the same location in the cloud, diffused by the cloud mass
through which it passed, and lit up the whole sky. I've not seen the like before or since. The next day
there was a -5 instability in southeastern North Dakota, along with several tornadoes (one reportedly
lasting an hour). Gene concluded: "There are things going on out there that we still don't understand."
You can say that again.'
- An account of the large and very powerful "Seymour II" tornado of April 2, 1980 (a year after the
Wichita Falls tornado), wherein a subsequent damage survey showed that even ditches and low areas offer
no safety against some storms. Six to nine foot gullies were found denuded of mesquite trees, with only
the stubs of cactus plants remaining, an almost complete scouring of all living matter. Pebbles were
found imbedded in the remaining and adjacent tree trunks, as if fired from a pistol. Of course, not, all
twisters are this powerful, so that ditches and gullies are still the safest place to be, when in the
open. However, there is evidence that on some occasions you should not expect to emerge from such
locations in the same condition that you went in.
- On hail. Gene recounted seeing a car roof beaten almost down to the seat tops. Chuck Robertson
reported that the Ringer, Oklahoma tornado cell dropped three different kinds of hail: golfball,
baseball and "snowball." The latter had a thick cover of soft ice, surrounded by a small ice core. When
the larger hail fell, it left little ice mounds or piles at each impact. Gene said that those who have
experienced it agree that there’s not much warning when big hail starts to fall: "You get a ping, a
bang, and then a crash!!"
VII. FEATURE #2
Clarendon Tornadoes
By Tim Marshall
(Editor's Note: An abbreviated summary of this storm appeared in the March
issue of Storm Data. The following is a more complete account.)
"On March 3, 1983, an early season storm system produced a total of five tornadoes in west Texas and
Oklahoma. I had the opportunity to photograph two tornadoes near the town of Clarendon, located in the
Texas Panhandle (Fig. l from Storm Data, March 1983, Vol. 25, No. 3, with chase route arrows added).
The day began with low overcast skies
in Lubbock. Temperatures were in the
low 60's and dew points in the low
50's. NSSFC forecasted a moderate
risk of severe thunderstorms along
the Red River Valley by late
afternoon. Seeing this, I had already
decided to chase that day, whatever
the chances, since it was the first
chase of the spring (and it had been
a long, hard winter you know!)
Figure 1
I went to the Lubbock Weather Service and plotted hourly surface analyses. As the morning progressed,
skies remained overcast in west Texas, but I remained hopeful that they would soon clear. By 11 AM, I
forecasted the most favorable area for severe weather to be from Lubbock (LBB) to Fort Sill, Oklahoma
(FSI) (Fig. 9).
A dryline was developing in southeastern New
Mexico and was moving eastward. In addition,
a warm front was becoming prominent from
Lubbock to near Dallas-Fort Worth (DFW). I
didn't want to travel too far from Lubbock,
since I was anticipating convection in close
proximity to the warm front-dryline
intersection. I chose the town of Matador as
the "target" town, since it was also south
of where previous morning convection had
taken place.
Figure 2
The upper air maps favored severe weather development in west Texas. The area was on the anticyclonic
side of the mid-level jet and the cyclonic side of the low-level jet (Fig. 2). With cold air advection
downstream and a closed low moving into central California, the upper level dynamics were becoming more
favorable for severe weather throughout the day. The morning sounding for Amarillo looked like the
'classic' bell shaped tornado sounding from Miller (1972). However, there was little or no wind shear
with height.
At noon, I left Lubbock and drove to
Matador. The sky gradually became broken
and small cumulus dotted the sky. A
tornado watch was issued along an axis
from Amarillo (AMA) to Mineral Wells
(MWL). Hearing those three beeping tones
on the radio brought back the sweet,
memories of last May. Naturally, my
adrenaline surged! I reached Matador at 2
PM. The winds were light southeasterly,
and the temperature was about 70 degrees.
I could see towering cumulus beginning to
develop along the Caprock escarpment to
the west.
Figure 3
At the same time, smaller cumulus overhead were beginning to dissipate. A small cirrus anvil could also
be seen to the distant north in association with a developing Cb. I called the Lubbock Weather Service,
and they informed me that the dryline was surging from Midland (MAF) toward Abilene (ABI). They said the
wind direction at Lubbock had turned southwesterly and the dewpoint had dropped into the 30's.
Meanwhile, the wind at Childress was backing more toward the east, and their dewpoint was increasing.
Since moisture convergence was increasing in the area, I drove northward toward the developing Cb.
From a rest area north of Turkey, I watched the Cb explode upward to my northwest. The storm was over
the Palo Duro Canyon and moving slowly northeastward over a sparsely populated area, with few roads. I
drove north toward Clarendon, hoping to intercept the storm. I arrived at the town about 4 PM and stared
almost in disbelief at what I was seeing. There was a large bowl-shaped lowering extending from the rain
free base, and it was rotating rapidly. ... I said to myself that this storm must believe it's a Maytype storm! (Later, I learned that it went from 38,000 to over 50,000 feet during this time).
I positioned myself just north of the
approaching lowering, just west of
Clarendon on FM 2363. Striations were
evident along the east and north sides
of the updraft. I had just set up my
cameras on tripods, when the wind
became calm and marble-size hail began
falling. At 4:50 PM, a large coneshaped funnel extended toward the
ground to my southwest (Fig. 3). The
updraft had a 'step-like' appearance,
and the precipitation area to the
north was quite small. The bluecolored tornado moved slowly northward
across rangeland (Fig. 4).
Figure 4
Figure 5
A clear slot could be seen wrapping around the
vortex. At times, a core could be seen within
the condensation sheath around the tornado (Fig.
5). The tornado began to turn to the northwest
and became rope-shaped, finally occluding in
precipitation at 5:11 PM. In all, the tornado
traveled about five miles in twenty-one minutes
and was rated F2 (Also, see Fig. 11). Meanwhile,
a second updraft developed just east of the
first and also began to rotate. I moved eastward
out of the path of the approaching updraft. A
cell merger was taking place, and the
precipitation area to the north was increasing.
Within minutes, precipitation was wrapping
around the lowering.
The lowering moved northward across
Rt. 287, and I could see cars and
trucks driving through the rain
curtains and under the impending
circulation. To the northwest, I could
see ominous looking cloud bands
spiralling up the east side of the
updraft (Fig. 6). A large inflow tail
extended eastward, demarcating the
boundary between the precipitation
area and the moist inflow.
Figure 6
About 5:45 PM, a rain-laden gust front rapidly moved
around the updraft, originating from the northwest.
As the gust front passed my location, a brief period
of rain fell, followed by a wind shift to light west.
I continued northward along Rt. 70 and stopped at my
second filming location, which was on top of the
Caprock escarpment, overlooking the Greenbelt
Reservoir. I could see the occluded updraft to the
north, with no apparent wall cloud. By this time, the
gust front had surged several miles to the east.
Then, at 5:59, a narrow column-shaped tornado touched
down right in the reservoir about two miles north of
my location (Fig. 7). A spray of water could be seen
around the base of the tornado. Meanwhile, a clear
slot wrapped around the updraft, such that the
Figure 7
updraft appeared as a giant cylinder.
As the tornado moved onshore, it suddenly widened into a large cone-shaped vortex. The tornado traveled
northeastward across Rt. 70, just missing the community of Howardwick. One person did suffer minor
injuries, when the tornado flattened a liquor store on Rt. 70.
I drove northward, underneath the darkened updraft,
and took a picture of the tornado when it was less
than a mile away to the northeast (Fig. 8). The
tornado resembled a long tube, and the core
extended to the ground. At times, the tornado moved
toward me, back over its damage path, reminding me
not to get too close. In all, the tornado traveled
about five miles in 23 minutes and was rated F2. I
took close to 80 slides and 250 ft of 8 mm movie
footage." Tim reported no tornado sounds of which
he could be certain. Noteworthy, however, was the
light 3-4 MPH winds beneath and adjacent to the
wall clouds; strikingly different from the 60 MPH
winds which Tim experienced along the wall cloud
boundary of the May 19 Pampa supercell (six large
tornadoes, plus one a mile wide). (Also, see Fig.
12)
Figure 8
'In order to better understand how the severe weather occurred, I plotted the 4 PM surface analysis
(Fig. 9). It is interesting to note how the warm front moved throughout the day. Note that most of the
tornadoes developed along the intersection of the temperature and dewpoint axes. It appeared that there
was enough lifting at low levels, either from isentropic upglide, upslope effects, or the dryline, to
force buoyant air above the inversion and begin the convective process. I learned that the forecast area
would have been more accurate, had I advected the area along with the mean surface winds. Then, in six
hours, the forecast area would have been closer to Amarillo.
Figure 9
Figure 10
Figure 11
VII. FEATURE #III
Australian Tornadoes
By Dr. Joseph H. Golden
A copy of the following climatology map on Australian tornadoes was sent to me by Dr. Joseph H. Golden.
It was one of several items sent, as a consequence of his six week trip to Australia last year. Joe went
as a Senior Visiting Lecturer in Meteorology to Monash University, near Melbourne. "They do get
tornadoes and waterspouts in Australia and Tasmania." Joe said that he "gave several talks to student
groups and to the Royal Meteorological Society, and aroused a good deal of interest in tornado chasing
(on the left hand side of the road!) Joe also photographed a funnel cloud near two New Zealand
volcanoes.
Map prepared by Stuart Allen
VII. FEATURE #IV.
Good Plains States
Severe Weather Radio Stations
By Mike Watts
(Editor's Note: Mike sent this prior to this spring's chase, but it couldn't be included
before now. Add this to your radio station lists for next spring.)
Wichita, Kansas
KFDI-AM
1070 KHZ
KBUF-AM
KBUF-FM
Oklahoma City, Oklahoma WKY
1050 KHZ
97.3 MHZ
930 KHZ
Seminole, Oklahoma
Kansas City. Missouri
St. Louis, Missouri
KSLE-FM
KLSI-FM
KSD-AM
KSD-FM
105.5MHZ
93.3 MHZ
550 KHZ
93.7 MHZ
Salem, Illinois
WJBD-AM
WJBD-FM
KGIM-AN
1350 KHZ
100.1MHZ
1420 KHZ
Garden City, Kansas
Aberdeen, South Dakota
C&W; Dramamine may be required but their
spotters are excellent.
One of our clients, should be the fastest,
with storm-related news in the area.
severe weather coverage for central and
most of eastern Oklahoma.
coverage east of WKY's.
concentrates on Kansas City metro area.
more familiar with the FM; its good with
storm information (one of our clients,
naturally) but concentrates on the
metro area; AM covers a greater area.
they are very good about severe weather.
concentrates on northeastern South Dakota.
Except for KFDI in Wichita, these stations are our clients and will immediately broadcast watches,
warnings and advisories that our office provides."
- - The next ST's Features will include John Weaver's Wyoming chase story "Close Encounters of the Revolving
Kind" and Eric Rasmussen's "Tornado Photogrammetry". Also in a future issue -- the antithesis of "The
Ideal Storm Chase" ... "The Abysmal Storm Chasers"
- - Corrections to last ST: Next to last page - Substitute "JVC CB-P5" for "JVC GZ-S3" and on last page Change "Sharon Springs" to "Sharon" and delete reference to "(Fig. 8)". [CD-ROM Ed. Note: Corrected]