Evening star. [volume] (Washington, D.C.) 1854-1972, 1891-11-25
A Fall Tornado.

To the Editor of The Evening Star:
Let the tornado come when it will it must
necessarily be the result of certain meteoro-
logical forces now well known to us. In a
certain sense there is nothing new under the
sum-" ALI the forces of nature are as old as
nature herself. and yet many OF them are
evidently hid from us and waiting only the
pro per time to be developed.
Bv the general public little is known of the
tornado. Even the physical Biographies of to-
dav reveal little or nothing of its nature, and
only by that very modern and valuable illumi-
nator, the weather map. are we enabled 70 COM
prehend it. Ii we will turn to the map of the
few days preceding this and other tornadoea,
We will discover, first, an area OF low barome-
ter travelling on a relatively north line. That
is, here on this continent, along line Of so de-
grees to IS degrees N. L. Second, we will dis
cover another slow further to the south and
west.
No tornado without heat. As the wind Is
toward the area Of low barometer, the '1ow''
far to the north Is producing the general heat
country, by engendering south winds. The
more southern low advances toward the
northern one.
Saturday. the 2lst, the southern 'low' was
sayans1 te ,ns valley Ley oendn ing
Atlantic seaboard. Where there is ''high''
there cannot be a low and the reverse. his
thigh" protected the Atlantic seaboard, and
even up to within half an hour of the tornado
there was little evidence Of the storm, even
though for two days it had been raining over a
wide expanse covered by the Mississippi valley.
On the morning Of the 2lst the south ''low''
was still little to the scuth and west of this
city of Washington. But from the high tenn
perature il was evident that the north Glow
held its own and that the south ''low'' was
travelling rapidly toward it. "High" was in
tho faI west, with advanced lines working
rapidly. toward the east. Even as late
as 1890 o'clock the clouds became
light and the sun shone through them as
though this ''low" was past; and even
prompted the suggestion that the storm was
by. The center evidently was The tornado
will take place in the track Of the 'lew." and
on this occasion it was true to the precedent Of
the law. By pm. the heavens were very dark,
by reason Of the heavy clouds brought to this
locality by the winds, and therefrom the pre-
cipitation was exceedingly heavy. An old say
ing, common with the boys generation ago,
illustrates better than anything else the nature
Of the tornado:
'Just before she does she doesn't"
The expression is mere slang, and was
never intended to illustrate scientific phe-
nomenon. 1t is merely one Of those
condolences sometimes met with. The tor
nado is nature effort TO establish q vacuum in
would be q physical impossibility. But the at
tempt has been made. The airs rush in behind
the hesting 'low" and counterfeit the effect; 90
lust before she does she doesn't"
Accompanying this tornado was little
thunder, and this was an additional evidence of
heat-a heat in the atmosphere that can only
be caused by the north '.low." The sumner
thunder storm and the tornado only differ id
intensity. They, are the, results Of the same
cause, only the tornado is the result Of more
intense action on the part Of nature.
These necessarily prevail far more during the
warmer months than during the cooler
months of the year, still there il no law
against them for any or for all Of the months Of
the year. But come when they will they will
only manifest themselves under the conditions
now SC well known to Us az the north slow"
The real cause lies many miles to the north
OF the effect SO while there 10 some advantage
to be gained by studying the local effect the
real cause must be looked for hundreds Of miles
away. Pm.
November 23, 1891.