New-York tribune., 1885-02-22
WHERE STORMS ARE MOST FREQUENT.
CHARTS ISSUED BY THE SIGNAL sERvicE-soMB
COMPARISONS OF RAINFALL

COMPARISONS or RAINFALL
series Of charts has been issued recently by the
Signal Service Office at Washington, appro ximately
showing the relative frequency of storms In various
parts of North America the North Atlantic and
Europe Twelve of these maps make the comparison
by months and thirteenth sums up the others In one.
The differences in frequency represented by various
shades of color on the same map The word storm
is here used to any of those well Defined broad
Of low atmospheric pressure, which in something
like process traversiug these northern lat-
tudes frequently starting In Western North America
and crossing the ocean, and sometimes extending into
Europe These barometric deprs ssions not always
energetic enough pre- duce much wind rain, II any
bu as thew arc essential factors n all Of the wind and
rain of the region they over the data thus gaph
cally presented in charts are interesting and valuable
both to mariners and landsmen wh) study the weather
Sergeant Finley who designed these charts. neither
discusses the theories nor cause OF storms nor draws
any deductions from his record. But the relative
frequency and generally eastward track OF storms are
made obvious at Ths. the in which storms
most often experienced Is in the form OF belt,
about six times large 1t is wide extending almost
due east and west, and having rounded ends. 1t
begins the western edge of Minnesota, runs juse
south of Lake Superior, includes the greater part Of
Lakes Michigan and HuroD embraces most OF tho
province of Ontario and the northern halt OF the lake
of that name, takes in Ottawa aud Montreal the
Adirondacks, and northern Vermont and New,Hamp-
shire, and stops just before reaching Maine and Que
bee
The next lower grade of frequency found in an area
which is merely an enlargement of the other tract thrco
times wide, and nearly twice as long lhe southern
outline of IL begins little east OF Bismarck crosses
the Mississippi the thern border OF Iowa. runs
thence almost due eastward to New-fiayen, passing
Just north OF NewYork City and then sweeps little
north of eastward to include all OF New England
and the eastern British provinces After curvIng
around Newfoundland the boundary turns westward 80
as 10 include the Gulf OF ST. Lawrence runs straight 10
be north shore of Lake Superior and then extends to
in Dakota The third tract OF neXG
lower frequency s again. an enlargement OF the pre-
ceding one. IL reaches from the Rocky Mountains
nearly TO the shores of Ireland. Its southern line takes
in Leavenwortli. Cairo, Cncnnati ana baltimore. mo
fourth tract begins. wedge point, at Oregon broadens
40 as 10 include NewOrleans. though skipping GaiYcs
ton takes in northern Florida, and then narrows as 10
crosses the ocean, The 9Th area that OF the least Ire
auency reaches to the Polar region on the North, l
cludcs all of the Pacific Coast of the United States. all
of Mexico but its southern part the eastern coast OK
Central America the West Indies and Northern Africa
and extends into Asia. Europe has some Local areas
corresponding the third and fourth grades, Oh TINS
side of her shores but Ike the hrt and second
The proportion of storms in these five ractas As io'
lows, In the first between IL and 10 N the second,
from to u; third, to - fourth s to y; lith >
less.
ASH would be q mistake however, TO infer that the
amount Of rainfall In various parts OF this country cor
re spends the relative frequency OF storm a. nero
indicated. Quite The contrary In the Lake region
and along the Canadian frontier where barometric de-
pressions are most plentiful the prccptatlQp ncud-
ing snow meedl amounts only to 80 0I 80 Inches an
nuay; whereas along the Gull OF Mexco "hero
storms are more scarce il amounts to 90 or TO- Ids
ia no doubt due the greater absolute humidity OF tho
warmer climate that storms there though less ife-
ouent than further north have more moisture TO Work
on Again. owing 10 the greater dryness ei the AR ~
the centre Of the continent than on the coast Bismarck
has only 20 inches rainfall incuding snow meltedl,
while Barnegat has 81 yet they both lie In the sAHs
belt of storm frequency.