Fulton County tribune. (Wauseon, Ohio) 1883-1925, 1914-01-23
HOW WEATHER IS FoRECAsTED

CiieTe Is SOInoCn1nS mysterious ana
occult about the work of the Wealth
er Bureau in forecasting the coming
of storms, frosts and floods. Not
few think that the observers must
necessarily get their data by reading
the planets, the stars and the moon.
AS a matter of fact the forecaster of
the Bureau foretells the coming of
disturbances in a businesslike way,
very similar to that in which a man
who has ordered a shipment of goods
would estimate the date of its ar
rival.
Suppose a business man had or
dered a carload of pineapples from
the Hawaiin Islands. He would
know the average time it would take
the steamer to make the trip to the
Pacific port, the average time for un-
loading and loading into refrigerator
cars, and the average number of days
to be allowed these cars for their
trip across the continent to New
York. His estimate, however, would
be subject to error because the steam
ship might be delayed by fog, or the
cars might meet with an accident.
Storms. ike pineapples, as a rule,
do not originate in the United States.
ehev come to US, some from the
Philippines, Japan, Siberia, Alaska,
Canada or the Gulf of Mexico. The
Weather Bureau gets cable tele-
graphic or wireless notice of a for
aign storm. Station after station, or
vessel after vessel reports the storms
arrival in its neighborhood, so that
the general direction and rate of pro-
gress can be determined very nearly.
In fact, the arrival of some storms
can be foretold ten days in advance.
The forecasters watch. for the re-
gion of low barometer which is the
storm center around which the winds
blow. This whirl or eddy moves bod
lily forward with the general east
ward drift of about $50 miles a day
in our ATTITUDES. AS the lines of
equal pressure (isobars) around the
low center crowd closer together, the
winds attending the storm increase
in. force. The forecaster determines
the direction of movement of the
storm and velocity.
When weather disturbances are re-
ported, the forecasters know from ex-
uerience about how long it takes them
TO reach our Pacific Coast, and then
how long after they will reach the
Atlantic Coast. For example. if
storm coming from Siberia drifts
eastward around the North Pole and
reappears in Alaska, it should ap-
uear in Washington and Oregon in
About two days; should get to the
Great Lakes in six days and to the
Atlantic Coast in seven or eight davs.
Unexpected conditions may delay
storms or divert them from the
straight track just as refrigerator
ear may be thrown off its schedule
or be shipped by accident on a wrong
road. Some of these storms deplete
themselves by running into regions
of high barometer which are of
greater magnitude and extent than
storm itself. Some of them, however,
travel completely around the world.
To keep tab on cold waves that
come into the United States from
Canada and Alaska, the Weather Bu-
reau studies the Canadian Weather
reports. England sends reports from
Iceland, the British Islands and Con-
tinental Europe, and daily reports
come from st. Petersburg on the con-
1itions in Russia and Siberia.
The same business system used in
tracing the track of storm is ap-
plied in determining the arrival of
frosts.
Flood forecasts are made in much
the same way. Information as to the
amount of rainfall at the head wat
ers of streams that cause floods are
covered by telegraphic reports sent
| by local observers. AS this rain
reaches the main channel, the height
| ofpthe water in the channel is deter
mined by successive gagins stations.
past records establish how much a
height say of 20 feet at Dubuque,
Iowa, will produce at Davenport, an
other station 80 miles down the Miss
issippi. This plan is followed all the
way down the river, and at each point
full allowance is made for the effects
of water from tributaries. and from
additional and local rainfall. AS a
result of these observations in the
recent flood, the people of Cairo had
warning a week or ten days in ad-
vance. The Pittsburgh district can
be given only IL to "a hours notice,
because a flood is upon them within
"a hours after heavy rain storm.