Evening star., 1941-11-06
Dry East, Wet West
Caused by Blocked
High
: Movement Of Greet
- Moss of Air Needed
" For Normal RuinfuII
BY THOMAS r. HENRY.

BY THOMAS r. HENRY.
"A blocked Bermuda high-a mass
4 relatively cool. dry air about
1000 miles in diameter and 5 miles
or more highs the cause of most
Of the queer weather the United
States has experienced this fall.
1t promises to be the second dry
@t autumn Of record in the East
4nd perhaps the wettest of record
u much OF the region between the
Mississippi and the Rockies. This
autumn has seen the ordinarily arid
Kansas get 25 per cent more rain
tall than the ordinarily wet Vir-
Kinia
The Bermuda high is a constant
Aature on weather maps. Its center
ordinarily lies somewhere over Ber-
5nuda. but it drifts eastward and
westward and increases and dimin-
ishes In normal years. This fall it
has been wedged westward and re-
mained for almost three months
without any change in size.
Barrier to Moist Winds.
Rainfall Is due mostly to tongues
OF warm. moist air which flow
northward from the Gulf of Mex
leo. They bump into the Bermuda
high as though it were a great. icy
mountain standing in their path.
They either must climb over it or
go around it and. if it is very high,
the course of least resistance is to
go around. The path always is in a
clockwise direction from west to
.$ast.
The high ordinarily does not rest
over the southern Appalachians for
more than a few days. 1t drifts
eastward and the moist air tongues
rush up over the Atlantic Coast
States. bringing rain. This fall they
persistently have been turned west
ward. so that all their moisture has
been dumped on the Mississippi
Valley and the Great Plains.
"It is" says DR.. J. B. Kincer,
chief of the Division of Climatology
OF the United States Weather Bu-
reau. "as II big moving van was
broken down at busy corner, tying
up all the traffic for blocks around"
Blocking Mystifies Experts.
Why the Bermuda high gets
blocked from time to time, weather
experts do not understand. Every
now and then this happens and
a titanic. unpredictable atmospheric
explosion of some sort is necessary
TO break it loose. The last time
it remained blocked for so long
was In the fall of 1880, the dryest
Of record for the East.
Ordinarily, the longer the high
persists the harder it is to break
up. and the longer the wet tongues
from the Gulf move over a given
path, the steadier the rainfall {.
Some idea of what has happened
the first two months of this fall
is CLEANED from Mr.. Kincers sta
tistics
Baltimore has had 1.18 inches Of
rainfall against q normal OF 6.46.
Washington has had 161. compared
to . 6.O8 normal. The figures for
GreenMlle. S. c., are 2.45. compared
to $50 for an ordinary year. Nash
vile has had 272 inches. while the
normal is 5.9l. Albany has expert
enced about half its normal fall
precipitation.
: :; On the other hand. Topeka, Kans.,
& has had 1o65 inches, compared to
q normal Of 242: Keokuk. Iowa, 16
$anches. compared 'to = normal Of
$40, and Springfield, ILL.,, 2036
slnches, against an average Of $40.
& East's Storage Drops.
q Fortunately, Mr.. Kincer points
sput. neither the dry nor wet weather
Is Of much importance 50 far IS
his years crops are concerned.
4 The storage of ground water IN
s4he East, however, Is nearly de-
pleted. It is ordinarily stored in
$4he late winter and early spring,
hummer and fall precipitation Just
srompensating for the drain Of crops
sbn the supply. Wells, Of course, are
%ry everywhere and city reservoirs
Are running low.
8 If the year follows expectations.
Ahere is little likelihood Of the sup
ply being restored until next Feb
3uary In the Southeast and March
Spr April in the North, where the
s&rozen ground prevents absorption
sof water by the soil
& How long the stagnation Of the
s6ermuda high will persist, Mr..
sKincer explains. is unpredictable. 1t
fvould not be expected to last all