Evening star., 1953-06-12
High Pressures Sturt.
Tornodo's Deadly Twist
Weothermen Con Neither
Blume Nor Absolve Bombs
By Thomas R. Henry

This is likely to prove q record year
for tornadoes in the United States.
May was record month. so far a.
Weather Bureau records show. June
may be worse.
The score to date:
January. 13: no lives lost.
February, Is; three dead.
March. ~: IS dead.
April, IS; "a dead.
May. 81; 124 dead.
First nine days Of June, 30. Deaths
unknown.
It cannot be said positively, however.
that these figures actually set records.
Reports in the past have been quite in
complete. Probably the majority of
these violent wind storms strike in quite
Sparsely inhabited country. A few farm
families may run to the storm cellars
when they see black, funnel-shaped
cloud approaching. It is all over in q
few minutes and may get few para
graphs in the county weekly. No ofi-
cial record is made.
Now network Of observers has been
set up in two Of the worst tornado
States. Oklahoma and Kansas. Some
body in every few square miles reports
a tornado to the nearest Weather
Bureau station.
More Storms Reported.
When one looks at the map on which
the storms are recorded, it seems, quite
naturally, as If Oklahoma and Kansas
had experienced about 10 times as many
tornadoes this year as any other States.
This Is simply because more have been
reported. 1t is probably a major reason
why this year seems to be setting a
record for the number Of violent wind
storms. There may have been worse
years, Weather Bureau observers say.
and Iowa, Missouri, Nebraska and Texas
may actually have had just as many as
Kansas and Oklahoma.
It's purely a matter Of chance if
tornado happens to include in its path
a city or town where it will cause great
loss of life and property damage. such
as Flint. Mich, or Worcester, Mass. AS
Weather Bureau observer said. Tive
often thought when I've looked out
the window of an airplane over the
Midwest what chance would have of
hitting any inhabited spot If tossed
out ribbon 20 miles long at random"
This year. it so happens, several
thickly populated areas unfortunately
have happened to be in the way Of
tornadoes, and this has made the rec
ord look bad.
The Nuclear Angle.
A popular idea seems to have gotten
around that the abundance Of torna-
does this year is due in some way to
atomic bomb explosions in Nevada.
The Weather Bureau is besieged with
inquiries about this and indignant de-
mands that something be done about 1t.
Bureau personnel see no reason why
one bomb, or a thousand bombs should
cause a tornado-eSpeciall thousands
of miles away from the explosion. Still,
they cannot state absolutely that there
is no association whatsoever. Too little
is known about the necessary upper air
conditions. Also, it cannot be stated
positively that there are more tornadoes
this year than last year, or 10 years
ago. 1t is only known that more have
been reported and that some Of them
have been unfortunately located.
The Bureau has an excellent tornado
foreeaSting and warning system. It
can tell when the atmospheric picture
over very wide area-uSually covering
several States-is such that it is pos
sible for tornado to occur. It cannot
tell whether one actually will take place.
or where it can be expected within the
critical area. Recent research has made
it possible to make somewhat closer
predictions. The bureau has gone ahead
with these warnings in spite of angry
protests from local chambers of COM
merce when nothing happens and trade
is ruined for few days.
Thick, Moist Air.
The typical tornado condition has
been recognized for years. The first re-
quirement is thick blanket of warm,
moist air covering the earth to an alti-
tude of 5000 to 5000 feet. This air
usually drifts in from the southeast
most often from the Gulf of Mexico over
the Middlewest. Above this must be
layer of cold, dry air, which usually has
drifted in from the northweSt-moSt
probably from the Arctic by way Of
the Mackenzie Valley of Northern
Canada just east of the Rockies.
This is a quite common condition
over tornado country. Most Of the
time there are no serious consequences.
When, however, something happens
nobody knows exactly what-to upset
the equilibrium of the two air layers.
conditions become such that tornado
is possible. Usually it doesn't happen.
Instead, there may be a series Of
violent thunderstorms. Often nothing
happens which attracts any attention.
~,
is that a tornado or other violent at
moSpheric disturbance is preceded by q
moving wave of spectacularly high
preSsureS. First, over certain limited
area-perhaps the size Of township
(36 square miles)-there is a sudden.
unpredictable, enormous increase OF
atmospheric pressure. It lasts about
five minutes. Then pressure returns to
normal Meanwhile, the sudden, spec
tacularly high pressure is observed over
the next township. Thus it goes for
anywhere from 20 to 200 or more miles.
The tornadoes, thunderstormS and
the like follow this wave. Weather
Bureau scientists interpret the phe-
nomenon generally this way:
The thick layer of moist. warm air
can be likened to an ocean of water.
Its surface is the So-called Inversion
layer" the surface where temperature
ceases to decline with altitude. The
cool, dry air above is like the atmos.
phere over the sea.
Ordinarily, the surface Of this air
sea is quite calm. It is, however, sub
ject to enormous waves, rising the
height of several hundred feet. These
waves are the areas Of Spectacularly