New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1890-11-12
FORECASTING THE WEATHER
GENERAL GREELY DESCRIBES THE WORK
OF THE SIGNAL SERVICE BUXEAU.
PERCENTAGE OF SUCCESSFUL FoRDcAsrs-THE
DEMAND FOR WEATHER MAPs-FACTs


CONCERNING ToRSADoDs.
Washington, Nov. 1.-THE annual report Of the
Chief Signal officer was made public to-day.
Under the head OF weather forecasts the Chief Signal
ooer speaks Of the inability Of the overworked force
to furnish regularly the numerous special predictions
asked for by cities. He says that the duties devolving
on the forecast Official permit less than one
quarter of minute en- average In which TO decide
and express forecast for State or district
With view Of subscribing the public interest by local
forecasts the Chief Signal Oficer has initiated the
plan of permitting officers and Observers in charge ID
stations outside Of Washington City to make local for
casts Of weather and temperature. The percentages
of successful forecasts 34.4 for weather. 1871 iof
temperature, and s2.6 as q general average During
the year 1ll2 storm signals have been ordered. OF
which 1O4O have been justified as to direction, 800
justified wholly as to velocity, and SO partly Is to
velocity. The accuracy OF weather and temperature
predictions has increased II per cent over the pre-
vious year; that Of storm signals remains pracucany
the same last year, 87.1 per cent. Longtime fore
casts OF weather and temperature have been issued AZ
the discretion Of the forecast OFFICIAL with successi
percentages Of 81.6 for forty eight hours and 800 LOT
seventy two hours These forecasts are made, not for
small areas, but for extensive sections Those Tor
seventy-twO hours In advance somewhat infre-
quent there being but 148 made during the year those
for forty eight hours frequent, and In number
reached 1, 1893.
Reference is made to the disadvantage under which
Professor RUSSELL who had the special duty OF fore
casting cold waves abored by reason OF more stringent
restrictions imposed General Greedy says that the
percentage Of verications o5O relates to the cold
waves forecast under the present rigid rule, but to
this might be added, In comparison with preceding
years. IA per cent Of other waves. which would have
been verified under previous rules There were but
fourteen occasions which severe cold waves were
not predicted in other words, 90 per cent OF all the
important waves forecast The record OF pre-
dIctons Of floods during the year given In detail ana
special Communication is awarded Professor kussep
for accurate prediction of the great floods OF the
Lower Mississippi Valley last spring 1t is said that
lack of funds prevents full development OF this
branch of the service. and Appropriation OF $1,000
Is asked for the purpose Of gaugng the ONO River at
various points With the establishment Of small
number of additional stations and proper investga-
ton of the river outflow in relation to gauge read
ings Professor Russell believes that accurate pre-
dictions three days In advance could be maze ior
Is are now made at Paris.
AS an evidence of the popular interest in the subject
the large ipcrease in the demand for the weather maps
f. cited 1t is said that these demands for weather
charts have increased remarkable extent. and their
use for general display and In public INSTITUTIONS ~
great that only IN cases has the Bureau fouhd
possible to issue these maps gratuituously, despite
the fact that hundreds have applied for them. Inc
number Of maps issued during the year Was ioo"'"1'
as against 17s,24s in 1877.
pesnactinU the weather crop bulletins, the report
says There Is no feature of this service which has
met with such universal favor and been SO highiy
valued rs the weather crop bulletin
Upon the subject OF State weather services, General
Greedy says he has decided to withdraw aid alter
January l. 1884, from such services as arc unable 10
print for the benefit Of their State the observations &C
cumulated and tabulated BY the Signal Service as
sstants.
Concerning tornadocs, the report says that In in
vestigating tornadoes great difficulty was experienced
In accurately determining property losses or loss Vi
Ife the difficulty resulting from exaggerated reports
For instance, the Louisville tornado, OF March S''
$780, was month later reported by the public press 10
have caused loss Of 500 lives, instead OF 13o-the
true number Professor Hazen divided the tornadoes
into three classes: First, violent storms causing
destruction third, the most severe tornadoes, and
placing in the second class all other known violent
storms While there were about 1000 tornadoes
each In classes one and two, causing the death OF
OIL people, average of one person to two storms
and loss of about $23, 900 600 In poroperty, yet
there were but hfegnt nd Gsstroyne proDery
to the amount Of sIl, sS4, 70or average loss Of
thirteen lives and over $4,000 OF property 70 s sasa
may destructive tornado be expected oftener on an
than once over in WITCH iS1 sss tSs
destcton can be expected is exceedingly SMALL even
in the states most liable to these violent storms Inc
chief signal Officer believes this matter OF great I'M
nortance and desires TO impress upon the people at
large how small the chances OF persona !afy Or
bowcver that In the last eighteen years the annual
death casualties from tornadoss average dC@ S Mns
great as the list of deaths from lightning, since during
present from March to Aa agS n compns
his record the list is incomplete, especially as Tegas
he southern States. 1t may be safely ass9mea oH.,
as are tornadoes, they are not SO
iifo fbuu derst