May 31, 1979 STORM-TRACK Vol. 2, No. 4

3415 Slade Court $2.10/year Bi-monthly
Fairfax, Virginia

I. COMMENTARY [by David Hoadley]
I have just returned from another three week storm chase from New Mexico to Colorado and Texas to
Nebraska. I drove 10,722 miles and photographed one small tornado southwest of Vernon, Texas, a
funnel cloud in eastern Colorado and a dramatic rotating wall cloud in southwest, Texas. By
comparison with other years, those last three weeks of May were very lean. The problem was a
series of cut-off 500 mb lows that dominated throughout this time period and kept the main storm
dynamics well north of the central and southern plains, during what should have been the peak of
the storm season. Many of the tornadoes that occurred were short, quick and difficult to forecast.
I was fortunate to have seen what I did.

Like myself, some of you also didn’t see what you came looking for, but let’s consider ourselves
fortunate that we were able to go at all. With fuel shortages casting long shadows over future
chase years, I consider any time spent in that historic land as memorable. There is the land of
the Arikara, Comanche, Pawnee and Sioux; a land full of sacrifice, pioneer tales and legends of
men we’ll never know. A land of arroyos, buttes, canyons and the wide open spaces that stretch the
eye and the mind. To chase storms is to be at one with the land and the sky; to “read” the clouds
is to touch a part of the infinite; and to exult in the majesty of a great storm is to expand
one’s vision and never again to think only of small things. Even in a “lean” year, there are
rewards.

II. ROSTER
III. BULLETIN BOARD/COMMERCIAL MARKET -$- FOR PICTURES
IV. CAMERA TIPS
FUNNEL FUNNIES: “It followed me home! Can I keep it?”

— Contributed by Charles Vlcek

V. TRAVEL TIPS [by David Hoadley]
For those of you still looking forward to chasing this year, my own recent packing added several
more items to the “Well Equipped Chase Car,” written up in the last issue of ST. Add the
following: Laminated 3/4″ by l foot square wood board to support tire jack base when changing
tires on muddy soil; fire extinguisher; jumper cables; handi-wipes to clean sticky/greasy hands
after quick food stops; tire pressure gauge; and roadside distress signs.

VI. FEATURE – Chasing Severe Rainbows [by James S. Lynch”>
Rainbows have often been considered to be the quiescent mark of a storm’s end, but some can
indicate the severity of a mature thunderstorm. During the Summer of 1978 while storm chasing in
Oklahoma and Kansas, three separate occurrences of unusual rainbows were observed.

These unusual rainbows were double rainbows.
A double rainbow consists of two other
rainbows, a primary and a secondary. A
primary rainbow is the outside rainbow,
having colors from red to violet with red on
the outer border. A secondary rainbow is the
inner rainbow with color bands reversed from
the primary, violet on the outside border.

The double rainbows were only seen when the chasers were to the west of a thunderstorm and the sun
was to the west of the chasers at an elevation between 5 and 40 deg above the horizon. Relatively
clear air existed between the sun and the storm. Also of note, a whitish precipitation shaft was
observed from the storm.

Upon entering the shaft, abundant rain and small hail was encountered, with hailstone diameters
from 1/8 to 1″. The Index of Refraction for water is 1.333 and for ice is 1.305 which indicates
that ice is a better mechanism for producing rainbows. Or are they called hailbows or hainbows?

All storm chasers are encouraged to keep an eye out for unusual atmospheric phenomena, and to
investigate the phenomena as completely as possible If anyone has experienced such hainbows,
please contact the following: James S. Lynch, The Severe Storm Intercept Project, P.O. Box 3305,
College Station, Texas 77840.

-Memorable Chase Days of this Year
On May 20, 1979, the National Weather Service forecast a few severe thunderstorms for northwest,
Texas and southwest Oklahoma. Starting from Childress, Texas, I photographed the storm that would
eventually produce five small tornadoes. Of interest was a comparison between this storm and that
of the Union City tornado of May 24, 1973. In this storm, the heavy hail/rainfall was behind the
outflow and southwest of the wall cloud, whereas in the Union City storm the heavy hail/rainfall
was northeast of the wall cloud (as is considered normal in the textbook example for this type of
storm). I understand that the reason for the exceptional behavior of the May 20 storm was the weak
upper level winds around the enclosed 500 mb low which failed to ventilate the storm’s midlevels
allowing heavy precip to fall out, early, through the core of the storm, prematurely terminating
its severe potential. As this cell moved northeastward through the moist environment, it continued
to regenerate and produced five tornadoes. Also pictured bere is the second of the tornadoes (one
that I photographed).


May 20, 1979


May 24, 1973 Union City


May 20, 1979 May 20, 1979 (tornado)

My next to last chase day, May 31, 1979, was also interesting for the location of two wall clouds
from one cell about 60 miles southwest of San Angelo, Texas. The second of the two was rotating
quite strongly and was impressive (San Angelo radar reported this as a “Level 6” storm, with tops
to 57,000′). The two wall clouds did not exist simultaneously, the first having “lined out” in
outflow before formation of the second.


May 31, 1979. Inset is 6:00 PM, left side is 5:48 CDT, right side is 6:30 CDT.
Next issue will feature an interesting article on “Severe Windstorms in Coloradoā€¯ by John M.
Brown.

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