The Minnesota pioneer. [volume] (St. Paul, Minn. Territory) 1849-1855, 1852-06-03
Climate Of San Francisco-The Sea
Breeze.

brcCZc.
! BY an analysis Of regular and careful OBJ
servatlons, daily recorded for more than
two years past. DIR. Ii. Gibbons deduces
many interesting laws regulating the blow
ing of the winds tina, prevail in aHd around
San Francisco. We cOndense The most
striking from Il report recently drawn up by
him. He lays it down as general rule
thar the westerly or sea winds predo;nnate
IN every month, except January and De-
cenbrr. increasing in frequency and force
from February to July, when they begin
to fall off gradually. Whatever may he
the direction Of the wind in the forenoon in
the spring, summer and autumn monlhs, it
almost invariably works round towards the
west IN the afternoon. During the seven
months from April TO October, inclusive of
last year, there were but three days in " hch
II missed, and those three days were all
rainy, with the wind from the south AMI
). s. w.
he sea winds of summer are commonly
supposed TO come from the Northwest.
But this Is great error, arising no doubt
! from the fact that our citizens have mostly
been accustomed 10 cold winds in the Al
ianiic States from that quarter. In the
early spring they sometimes proceed from
north of ". Il. As the season advances
they depart entirely from this course, and
are almost invariably from south OF west.
From May To September, a period of i've
months, the direction of the afternoon sea
breeze was north of west on twelve DAYS
only; and even on these occasions it was
lsily within one point OF west. The pre-
vailing direction was west south west.
Out of one hundred aud sixty-,wo days,
the afternoons of which were windy, but
>even were windy at sunrise.
The sea breeze generally rises to It's
height soon after uonn-lay, mostly between
one anl tAo O'Clock, hut sometimes not till
three or four. 1t commonly falls about
sunset, or soon after Sometimes it con-
uinues I'LL midnight. In the early part of
the season it is apt 10 set in earlier and con-
TIME later. / here were windy evenings
in May, l IN July, in August, and none
IN September.
The idea of mis-, and vapor is commonly
associated with these winds; hat the sky is
clear, Or partially so, more than halt the
time. There were cloudy mornings in
! May, I in June, g 10 July, 81 in August
and - IN September About or 10 o.
clock, the clouds mostly broke away rap
IDLY, a light breeze sprjnging up al the same
time. Several hours of very pleasant wealth
e. occurred towards noon, airnos, every
day. The snn shone forth with genial
warmth, the mercury rising generally from
about so at sunrise, 10 60 or Go at noon.
But when the sun mad reached the zenith,
the wind rapidly increased, coming down
in gusts from the hills, which separate the
! ciiy from the ocean, AMI often bringing
with il clouds of mist. Bat the danpness
Is never sufficient to prevent The elevation of
clouds of dust and sand, which sport through
the streets in the most lively III amer. L he
mercury falls suddenly, and lon. before
sunset II fixes itself wlthn few degrees
ABOVE 30, where It sticks pertinaciou-ly an
I'll next morning; often not moving a hairs
breadth for twelve hours.
No one but an actual observer can appre-
ciate the utter nnpotency Of an almost YER
teal sun, during brisk sea breeze. The
rays of the snn have scarcely more warmth
than mnon beams In>jead Of raising the
tbernome:cr so or 40 degrees, they seldom
produce more than TEL degrees OF elevation,
IN tbe sweep Of the WIND.
In all other parts of California, except in
the region about the Bay Of San Francisco.
the summer is very different. long the
coast are mists and sea brerZes, but the
WINS are moderate, and not 80 chilling.
inlsud, they do not extend heyond the bar
r.rr OF hills, which skirt the coast. 4 dis
tance Of fifty miles iii any direction from
! San Francisco brings Nuu HItp a different
climate. In a southeast course, tDwardS
San Jose you escape The winds and logs Of
summer ny travelling 90 or SO miles. Even
in Contra Costa, directly across the Bay,
they are less severe, though the trees show,
by their PROSTATE attitudes. the direc-
ton of the prevailing atmospheric currents.
The general principles on which depend
the duruai currents of air, which SET IN from
sea to land are we'll known. The land be-
IN. more heated than The ocean by the sun
RAYS, the slperincuinbent heated air rises III
Il steady column. Its plarc must he sup
piled from some quarter, ami the r"drr
and deuser air of the ocean accorllHgly
flows IN, constituting sea-breeZ". indie
ppnlen,y of this, we have the universal
westerly current, conci.ling ~ IL course
and tending TO add strength and con~fancy
10 the sea-breeZp, while the topograph.cai
FEATURES Of the Bay Of san Francisco, ami
the region Of country bordering on II en-
hanre the effect. 1 hese severa cause.
combined, will explain the extraordinary
con-t nry and force of the westerly wind.
at this point.-( san Fran. Herald.
The CHIvEsE.-rhe pettcoa'ed gentry
/ i,o hnl. ri, fpI