Little Falls weekly transcript. (Little Falls, Morrison Co., Minn.) 1894-19??, 1896-04-03
STORY OF WEATHER


ASTORY OF WEATHER
WHYTHE MONTH OF MARCH IS OFTEN
CLUSTERING AND STORMY.
Some Facts About Weather Changes-Cold
Currents From tho North and Warm
Ones From tho South-Enects Of Mag
netio Force.
March impresses itself upon the dwell
er in the northern half Of the United
States as q particularly windy and dis
agreeable month, with strong alterna-
tions of wintry and mild weather. This
ia due to the breaking up of the condi-
tions that have prevailed since Decem-
Der and the processes of return to spring
and summer. There is in the arctic zone
an enormous amount Of cold material to
be disposed of, covering the northern
regions in the form Of ice and snow. At
the same time the southern zone is be-
coming decidedly warmer in conse-
quence of the advance Of the sun to the
northern side of the equator.
The United States is peculiarly the
theater of this contest between the
giants Of cold and heat, and they stag
ger back and forth over this territory as
one or the other is for the time being in
the strongest form. The cold, waves
launch themselves from the north and
carry their icy chill to the warm south
ern states; or, on the other hand; the
warm currents Of air from the south ad-
vance far into the north, and this alter
nation causes a rapid variation in the
temperature and the other weather con-
ditions at stations of the middle lati-
tudes.
An examination Of the storm tracks
for March gives very definite evidence
of the effect Of this struggle for suprem-
acy. Instead of being confined to the
neighborhood of the mean tracks, it is
found that they spread out over the en-
tire territory of the United States from
north so south. The phenomenon OF
looping southwark along the Rocky
mountain slope before recurring north
eastward to the gulf Of St. Lawrence ia
most pronounced.
The storms which first develop in AL
berta or on the north Pacific coast may
advance directly eastward over the lakes
to the gulf, or they may be pushed south
and recurve in Colorado, Missouri, south
ern Illinois or southern Indiana, in or
der to move to the St. Lawrence val
ley, or else they may be propelled still
farther south along the Rocky mountain
slope to Texas and the gulf coast, whence
they proceed to the south Atlantic coast,
and then turn northward to Newfound-
land. Not few Of these storms dissi-
pate in the lake region or the Ohio val
ley; others will persist in path Of
nearly 5000 miles, from Alberta to
southern Texas, South Carolina and
finally to Newfoundland. The unequal
distribution Of the tracks Of the storms
in March is therefore due to the irregu-
lar propulsion Of cold masses OF air from
the arctic regions into the middle Of the
North American continent. "' ii" e.;
A popularity Of continental action is
that in summer the interior is warmer
than the borders, but in winter the in
terror is colder than the coasts. The up
per lake region and the upper MISSISSIPPI
pi valley are especially remarkable for
this feature. Between the IS degree and
100 degree meridians, and between par
allels 80 degrees to 55 degrees, the
change in temperature is the greatest
known in North America; it is coolest in
winter there, and also it may become
the hottest part of the country in sum-
mer; the range Of temperature may be
from 45 degrees below zero in winter to
lO5 degrees above zero in summer, a
range Of $50 degrees. The encroach-
ments Of spring upon the winter in
North America proceed from the ex-
IRENE southwest, the gulf Of California
and the Colorado river valley, and adj
vance toward the northeast.
This leads to description Of one Of
the most characteristic features Of the
advance of the summer upon the North
American continent. In winter the lines
of equal normal temperature, that is,
the isotherms, are grouped about the
cold pole in quite symmetrical man
ner, bending southwark In the interior
as they pass from the Atlantic to the
Pacific coast. This configuration may be
regarded as normal from November to
March inclusive. In the summer the
formation is somewhat inverted. the
lines bending northward from the coasts
toward the interior. though the crest is
now farther west in the dry Rocky
mountain region. The gulf Of Califor-
mia is the central region Of heat. and
the crest extends from Yuma, A. T.,
northeastward toward the Dakotas.
The magnetic force seems to be eff
oient in producing meteorological effects
in proportion as it can operate in cold
atmospheric conditions Hence the en-
croachment Of warm air from the south
ern Rocky mountain districts, as spring