The National tribune., 1890-12-18
THE WEATHER,
by LIEUT.. j. p. FIELEY, U. S. SIGNAL sEnvIc
Some Points on Pacific Coast Weather.

by LIEUT.. j. p. FINLEY, U. S. SIGNAL SERVICE
correspondence invited suggestions desired,
and information cheerfulIy furnished. Every ef-
fort employed 90 make this Bureau Of practical
10 the readers OF THE NATIONAL TRIBUNE All
communications should he addressed Weather,
THE NATIONAL TRIBUNE Office, Washington. ID. G.
No discussion, however brief of Pacific Coast
weather would be complete without a recog-
milton of the two seasons SO well known on this
coast as the period of rain aud the period of
dry weather. This division has peculiar sig
nifcance, which is not fully appreciated in the
East. by the expression dry season." we do
not mean an entire absence Of rain, but rather
such cessation Of precipitation during a GER
tain period as to form a decided contrast with
the period during which the rain falls more
frequently. We cannot enter into a. lengthy
discussion Of the causes that underlie the pc
culiar distribution of rain which give rise 10
the sO-called wet " and dry" seasons. At
tention must be briefly called 10 the fact that
practically all OF the storms which enter the
Pacific Coast proceed from the Pacific Ocean in
the vicinity Of the Aleutian Archipelago.
This is the breeding-gr0und Of the storms of
the North Pacific. Some Of the storms which
enter upon this coast are traced directly from
the Japan Islands, The typhoOn Of the China
and Japan Seas may become later on in its course
the violent cyclone which sweeps the coast Of
Oregon and Washington with great fury. The
course OF these storms are nOTthwestward from
the Asiatic coast TO Boring Sea. thence curving
sOutheastward to the coast Of British Columbia
and the United States The period Of greatest
frequency and intensity of these storms coin
cides with what is known in the Pacific Coast
States as the :" wet season."
There will be variations in the amount OF
rainfall during this season, as there are yaria-
tions m tho frequency Of storm areas from the
North Pacific Ocean. Storms from this great
region Of atmospheric disturbances have been
traced from the Japan Islands 10 the United
States, thence across that country TO the At
lanLic, across that ocean 10 Europe, and over
Europe to Russia. In fact, the storms path
from inception 90 termination made the circuit
OF the earth. How enormous tho proportions
OF such ripple in the atmospheric sea of this
planet During the " wet season on the Pa
elhc Coast there is marked increase ia the
number OF storms passing over the North At
lautic and during the dry season there is
decided diminution in the number traYeTsing
that ocean. In the Summer all storms move
eastward at a higher latitude. .ua-
This Is due 10 the more vertical position OF
the sun over the Northern Hemisphere. thus
Increasing the heat aud moisture of the air i'm
the Temperate Zone In the Winter the re-
verse takes place and the storms move east
ward AT lower latitude, giving rise in the
Pacific Coast States 10 greatly increased pre-
cpltation As the storms move eastward at
much higher latitude in summer the Middle
Plateau region aud California are compelled TO
get their rain at this time OF the year from the
snow deposit on the mountains Under the
influence OF Midsummer's heat the snow is
constantly evaporated, producing heavy clouds
that drift away from the pea * over LhG galleysy
and there descend ana dtss6ftt In hcopi01rs
showers No snow in Winter means no rain
IN Summer for the Middle Plateau and Cali
f0rnia.