Evening star. [volume] (Washington, D.C.) 1854-1972, 1945-03-03
Letters to The Star
Spokesman for Weather Man
Tells His Side of Forecastin9

| quested an explanation of the inaccu-
| rate weather forecasts occasionally
reaching the public.
The magnitude of the problem faced
by the meteorologist is known to only
small number of people. Using his
science and instruments as weapons,
the weather man wages an increasing
war upon the atmosphere. He tries to
anticipate the next move of mon
strous foe which is attacking on all
sides, at all times, with an emphasis on
| air power.
John @. Public has little desire to
| hear about the weather mans troubles.
| John just wants results. And so the
| meteorologist, in the public mind, Is
either an elderly mystic or a dreamy
scientist who gazes at strange instru-
| mentS, draws a tangle of lines across
his maps and charts and then gives
utterance to several stereotyped phrases
which provide vague picture of to-
morrow weather.
Actually, the meteorologist is SCI
enlist whose difficulties are unfolded in
the following paragraphs:
The first weapon of the forecaster is
his knowledge of the weather over
very broad area, such as the continent
of North America plus some portions
of the surrounding oceans. The neces-
sary information is furnished at regular
intervals each day by an army of
weather observers in hundreds of cities,
on mountain tops and on ships at sea.
BY radio, telegraph and teletype all
observations are assembled and then
poured into the district forecast center.
An orderly presentation of this mass
OF data Is now obtained by writing down
the weather information at several
hundred stations represented on large
map of North America. Since the
weather that we witness on the surface
of the earth is the result of activity
far above the ground, dozen different
maps must be made to show conditions
at various levels high in the atmosphere.
Why Mistakes Occur.
All of this work must be done on
spllt-second schedule. The forecast will
suffer because of any factor which pre-
vents correct information from appear
ing on time in It's proper place The
weather map Is the raw material of the
weather service. The completeness of the
map can suffer from the following
causes:
l. Too few observations: over oceans
because of wartime radio blackout; over
uninhabited land areas; in the upper air
because of lack of funds and because the
best instruments yet developed are in
adequate.
2. Communications breakdown: any
weak link in the chain of teletypes re-
suits in blank space on the weather
map, since teletype schedules are too
full to allow repetition of reports
garbled or completely lost
3. Human failure observers and map
makers make mistakes due to the pres
sure of time
The tools used by the forecaster are
scientific instruments, slide rules. and
rules for forecasting. Unfortunately, sci
ence and mathematics still are made
quate to deal with more than a greatly
Slmpllfied version of the problem pre-
sented by an enormous sWirling three
dlmenSloned fluid such as the atmos-
phere. The forecaSter must use his ex-
perience with past situations to bridge
the gap between the simplifed picture
solved by mathematics and the actual
picture lying before him on his weather
charts.
Storm Tricky Foe
We well may imagine a particular
storm to be an army attacking us from
the west. Our intelligence service is
directed to give us all obtainable infor-
nation. but our adversary is able to keep
secret many vital facts, and so we are
able to get only an incomplete picture
of his present strength and movements.
From what we know, we must Judge
whether the enemy (the approaching
Storm will change his speed and direc-
ton as he approaches and to what ex-
tent he will increase or decrease his
strength. A snow storm that arrives
unprotected is analogous to a great air
raid which is conducted by bombers
whose precise strength has been kept
secret and whose approach is a feint
along a route leading to another sec
ton of our country.
The weather forecaster. after a fail
ure, tries to find out why he failed. He
now has far more knowledge of the
situation since he is able to work back
ward, and, more important, whereas
he issued his forecast in just one hour.
he now uses any spare time during the
next week or month to sift through the
available data The conclusions made
from this research will help him make
better forecast if similar situation
ever should develop again.
The Army is not disbanded because
single engagement is lost and so the
Weather Bureau always will be an i'm
portant agency in protecting the public
from harm from the elements. Like the
Army, it will attempt to obtain we'll
trained lieutenants and then will place
the critical position of forecasting me-
teorologist. S. TEWELES.
Advocates Physicians Garage
To the Editor of The Star:
1t seems to me that in this particular
time of rationing and distribution that
one of the most imDortant factors tn