MARCH 1959 MONTHLY WEATHER REVIEW 111 il
THE WEATHER AND CIRCULATION OF MARCH 1959
Record Cold in Alaska But Mild Temperatures in the Remainder of the United States
CARLOS R. DUNN
Extended Forecust Sectlon. U.S. Weather Bureau, Washington, D.C.
1. INTRODUCTION l'ositions (indicated by arrowheads on heavy dashed lines
The departures from normal of circu1:holl and l e u -
perature for March 1059 were rather small over most of
the cont,iguous United States. Westerly flow, silnilar to
the normal [6], prevailed in the mid-troposphere, and
maritime polar air masses, with their moderating, spring-
time effects, dominated the weather. However, the pre-
cipitation was more abnormal. There were periodically
heavy rain and snow falls as vigorous Lows developed in
the Southwest and moved across eastern United States.
Some regions received 200-300 percent of their normal
precipitation.
In sharp contrast to the nlild weather ill the contiguous
States was the bitter cold throughout the State of Alwka.
Long-period Alaskan records were broken, and the
reported mean temperatures were more typical of micl-
minter than early spring. For example, the monthly
mean temperature at Barrow was a frigid 27" F. below
zero.
Meanwhile, the Hawaiian Islantls had unnsually war~n?
dry weather. Honolulu, for example, reported n record
high mean temperature and lit,tle precipitation. There
were just 6 days with measurable rai~lf:rll, and tlle total
for the month was only 7 percent of normal.
2. THIRTY-DAY MEAN CIRCULATION
The monthly mean circulation at 700 mb. for Marc11
1959 consisted of a large-amplitude, three-wave pattern
in high latitudes and n smaller-amplitude, four-wave pat-
tern in middle latitudes (fig. 1). These two vave trains
were approximately 180" out of phase. Only the trough
in Eurasia extended continuously across all latitudes, and
even it had a marked slope from northeast to southwest.
Associated with these truncated, out-of-phase troughs and
ridges were several confluence zones with accon~panying
strong winds. The most prominent ones were in the At-
lantic and eastern Pacific, where the height anon~alies
(fig. 1) indicate stronger-than-norlrlal westerly geo-
strophic winds. I n fact, wind speed maxima were located
in bot,h of these regions, and mean spwls ~1 -e more tIm11
8 m.p.s. above normal (fig. 2). The ce~rter i n the Atlantic
was a primary wind maximum, but the one in the eastern
Pacific was essentially just an eastward extension of a
larger primary wind maximum located in mid-ocean. All
of these wind speed maxima were dl east, of their normal
i n fig. 2).
' In Eurasia the mean winds were generally weak. Re-
sidual blocking over Europe, which was associated with
n split jet stream, produced a large area of subnormal
wind over central Europe but supernormal wind to the
nort,h and south. One jet stream axis was depressed and
flowed across northern Africa ; the other was displaced
north of the normal position, producing wind speeds up
to 9 m.p.s. above normal between Scandinavia and Spitz-
bergen. There were no organized jet streams at the
700-mb. level over Asia.
Returning to the 30-day mean circulation over the oceans
(fig. 1), we note that the troughs as well as the primary
wind maxima were displaced eastward from their normal
positions. This eastward shift of the Asiatic coastal
trough resulted in above normal heights and abnormally
anticyclonic conditions over Japan and eastern Siberia.
The cyclonic areas were also displaced eastward, produc-
ing significant negative anomalies in the central Pacific
Ocean and Alaska.
The largest anomalies were in northern latitudes, where
the 700-mb. heights were far enough above normal to re-
sult in a High over Kamchatka, the approximate location
of the normal Low, and also far enough below normal to
produce a trough over Alaska, near the position of the
normal ridge. This anomalous situation affected the
downstream pattern, so that the trough normally found
over eastern Canada was displaced approximately 25" of
longitude eastward to southern Greenland, reducing
heights in that area to 510 feet below normal, the largest
anomaly in the Northern Hemisphere.
I n retrospect, it appears that the block over Europe and
the unusually strong trough in western Siberia, through
tlle flux of vorticity, molded the well-marked wave train
downstream. I n addition, the eastward displacement of
waves was favored by stronger-than-normal polar
westerlies.
I n the United States 700-mb. height departures from
normal were snlall (fig. 1). Over the western States posi-
tive anomalies were associated with the flat ridge along
the coast. I n the eastern States there were weak negative
anomalies over a broad band, typical of a flat mean trough.
The latter feature suggests that cyclonic activity during
March was uniformly distributed over the eastern two-
thirds of t,he United States.
112 M O N T H L Y W E A T H MARCH 1959
FIGURE 1.-Mean 700-mb. contours (solid) and height departures from nornlal (dotted), bothin tens of feet, for Mmvh 1959. Mean
ridge in the western and trough in the eastern United States were assoc.iatetl with stormy \\.rather vast of the western niassif.
Abnormallydeep trough brought cold weather to Alaska.
MARCIX 1959 MONTHLY WEATHER REVIEW 113
FIGURE 2.-(A) Mean 700-mb. isotachs and (B) departures from
monthly normal wind speeds, both in meters per second, for
March 1959. Solid arrows in (A) indicate principal axes of
maximum winds, and dashed arrows their normal March posi-
tions. Regions with wind speeds greater than 15 1n.p.s. and
anomalies greater than 5 m.p.s. are stippled. Principal wind
maxima were located over the Oceans east of their normal
positions.
4. RECURRENT CIRCULATION AND WEATHER
The 5-day mean flow patterns during March resembled
each other and were quite similar to the 30-day mean flow.
This is illustrated by the geographical frequencies of
FIGURE 3.-Difference between monthly mean 700-mb. height anom-
aly for February and March 1959 (March minus February) in
tens of feet. Largest falls were over Great Britain. Changes
in many areas have striking resemblance to 700-mb. height
anomalies for March (fig. 1).
700-mb. 5-day mean troughs and ridges (fig. 4) and by
their relationship to the 30-day mean chart (fig. 1). The
bands of high frequency of troughs and ridges were nar-
row, indicating a small variation in the longitudinal p s i -
tion of the troughs and ridges. One except,ion is the
eastern United States, where the 5-day mean troughs were
rather uniformly distributed from the Mississippi Valley
to the Atlantic Coast.
It is particularly noteworthy that the positions of the
5-day mean troughs and ridges clustered around their
respective 30-day mean troughs and ridges. This means
that the 30-day mean accurately portrayed the predomi-
nant circulation regime of March and was not merely the
average of several heterogeneous, short-lived circulations.
The 30-day mean flow of small amplitude across North
America was accompanied by zonal trajectories of the
Highs for March (Chart IX in [4] ) . The continental
polar a.nticyclones, which formed in western Canada,
glanced east-southeastward and remained almost entirely
in Canada. They affected only the northeastern United
States where the monthly me'an thickness (fig. 5) and
surface temperatures (fig. 7 ) averaged below normal. The
remainder of the United States was dominated by mari-
time Pacific air masses, which also moved eastward across
the country. A few anticyclonic centers had trajectories
from the Pacific through the Northwest, but many of the
Highs first appeared over the Plains and Central States
nnd subsequently moved eastward into the Atlantic Ocean.
FIGURE 4.-Percent of the time that (A ) troughs and (B ) ridges
on 5-day mean 700-mb. charts were located within 10" longitude
intervals at latitudes from 20" N. to 70" N. for March 1959. The
data were adjusted to an equivalent basis with 10" a t GO" X.
as the unit. Isoline interval is 20 percent. Areas with fre-
quency greater than 20 percent are stippled; zero areas are
hatched. Note high frequency of troughs and ridges 1le:Ir the
locations of the 30-day mean troughs and ridges, respectively
(fig. 1 ).
These maritime air masses had a thickness or mean tem-
perature of the layer from 700 to 1000 mb. that mas xbore
FIGURE 5,"Departure from monthly normal of the mean thick-
ness (700-1000 mb.) for March 1959 i n t e n s of feet. Isoline
interval is 50 feet. Below normal values are stippled. Pattern
over the United States bears a striking resemblance to the sur-
face temperature anomalies (fig. 7 ). Extreme negative de-
partures over Alaska were associated with record cold weather.
normal for the northern areas of the United States. This
was particularly true for Montana and the Dakotas, where
in March continental polar air masses are required to pro-
duce subnormal thickness, However, the same maritime
Pacific air masses produced below normal thickness in the
southern States (fig. 5 ).
The same was generally true for the accompanying sur-
face temperatures (fig. 7 ), but this month an exception
existed in the Far Northwest where subnormal surface
temperatures were associated with above normal 30-day
mean t,hicknesses. The coolest weather here occurred dur-
ing the second and fourth weeks [7 ], when there was a
strong flow of abnormally cold air from the Arctic and
Alaska (fig. 5) into the Northwest. These air masses had
a short and rapid trajectory 0~7er the ocean, thus minimiz-
ing the diabatic heating, so that the air was still cool when
it reached the northwestern United States. During the
fourth week t'he cooling v a s further enhanced by cyclonic
flow aloft.
Along the California coast the weather was unusually
warm. Both San Francisco and San Diego, which have
long periods of reaord, reported new high mean tempera-
tures for March. Furthermore, temperatures averaged
above normal every day of the month at San Diego and
were belov normal only one day out of the month a t Sa11
Francisco. Previously, se.veral authors [l, 31 of this
series of articles have related the persistently above nor-
mal temperatures in recent years along the California
coast to abnormalities of the circulation and of sea-surface
temperatnre. This Mamh the record high temperatures
b b C H 1959 M O N T H L Y W E A T H E R 115
BIQUEE B.-Tracks of selected major cyclones which produced intense storms over the United States during March. Circles are the 1200
BMT locations of cyclone on date indicated by number abore position. Number below is central pressure of Low in tens and units of
millibars. Each week at least one severe storm moved out of the Southwest producing heavy snow and rain ever large areas east of
the Continental Divide.
follow directly from the above nornml heights at 700 mb.,
and in addition, from the greater than normal north-
easterlyflow at 700 mb. and sea level, produciqg foehn
winds for the area south of San Francisco (fig. 1, and
Chart XI in [4] ) .
The cyclones, with two exceptions, wllicll had tracks
over the United States also had origins there (Chart X
in [4]). Several Lows formed in the Atlantic Seaboard
States, but the storms which originated in the Southwest
contribute'd most to the weather over the United States.
Each week at least one major cyclone formed over the
southern Rocky Mountain States and produced severe
weather along its eastward track through the central and
eastern United States. A detailed descripition of the
effects lof these storms is given in [7].
During the first week of March a major storm marked
by heavy rains, damaging winds, blowing dust; and drift-
ing snow moved from Colorado northeastward across the
Great Lakes into Canada (fig. 6A). The weather during
the second week was influenced mainly by two disturbances
which reached strong storm intensity as they moved north-
eastward (fig. 6B). The first storm, 11th to 13th, moved
erratically from the lower Mississippi Valley to a posi-
tion just off the north Atlantic coast and finally turned
northward across eastern Maine. This storm produced
heavy rains in the South and heavy snows in the North-
east, as high winds raked the entire east coast. More
heavy rains in the South and a band of heavy drifting
snow from Nebraska to Michigan resulted from the second
storm of that week (14th to 16th) which moved from the
lower Great Plains across the Great Lakes. During the
third week the incidence of Southwest storms continued,
but the cyclone which formed over Utah on the 19th moved
in an east-southeasterly direction with its path traversing
the Gulf Coast States (fig. 6C). I n addition, a cyclone
formed over Lake Ontario and slowly traced an erratic
track across the Maritime Provinces of Canada (fig. SC) ,
creating stormy conditions in New England on March 21.
The mild, sunny weather east of the Rocky Mountains
during the first part of the fourth weekof March was
116 MONTHLY WEATHER, REVIETV MARCH 1959
FIGURE ?‘.-Departure of average surface temperature from normal
(O F.) for March 1959. Largest anomalies were in the northern
Plains and Rocky Mountain States, but the positive anomalies
along the California coast were associated with rerord ten)-
peratures (from [ 71 ).
F r u u s ~ 10.-Nuinber Of days in March 1959 with fronts of any
type within unit squares (with sides approximately 500 miles).
All frontal positiolls are taken from UrriZyl Weather Uup, 1:oO
p.m. EST. Arras with le> or more days with fronts are stippled,
Active fronts \vew frrqlwntly loc2:ited in Florida, Central Plains,
and the Nortlnvrst.
FIGURE 8.-Total precipitation (inches) for March 1959. Record
amounts fell in Florida (from 171 ) .
FIGURE 9,”Percentage of normal precipitation for March 1959.
March was abnormally wet in the southeastern, northeastern,
central, and northwestern States but unusually dry in the north-
ern Plains, northern Rocky illountnins, and the Sol1thwPst
(from [71).
interrnpted by sternly ~veather :IS still anotller Texas dis-
hrbance rnovetl northe:~stward on the 25th to 27t)h from
the Southwest. across New Jersey (fig. 6D).
The severity of the weather associated with these
“Southwest, IIows” is attested by the summary ofthe
monthly weather at Dnbuque, Iowa, which felt t,he f ~d l
brunt of several of these storms. It was reported that
the precipitation for March was the heaviest since t h e
beginning of records in 1851. The snowstorm of the 4th
and 5th brought the greatest amount of snow ever re-
corded in one 24-hour period for any month. The 6.50
inches of moisture for the month exceeds by 1.48inches
the previous wettest March recorded in 1852. The total
monthly snowfall of30.2 inches is the greatest for any
March and the greatest for any month of the year since
January 1929. Similar reports of record-breaking weather
came from stations in Nebraska and Wisconsin.
The hulk of the precipitation over the United States
tl1wing March (figs. 8, 9) was produced by the major
storms whose tracks are shown in figure 6. However,
additional rainfall did occur in the Southeast, associated
wit,ll fronts which were prevalent over Florida and the
Gulf ofMexico (fig. 10). Some of the precipitation was
cold-frontal in nature, but) the majority was produced by
inc,ipient,cyclone waves alld over-running of the cold
air by tropical air masses. Tampa reported the wettest
March on record; ot’her Florida stat,ions broke various
precipitation records.
I n the Northwest above normal precipitat,ion occorured
with f:~ste~~-tha~~-normn.l ~z.est,-so~lth\~esterly flowacross
MARCH 1'359 M O N T H L Y W E A T H E R 117
the mountain ranges (fig. 1) , which intensified orographic
lifting. Also favorable were the frequent invasions of
maritime Pacific fronts (fig. 10) and cyclonic flow aloft.
(See DaiZy Weather Map [ 51 .)
That precipitation which fell east of the Rocky Moun-
tains occurred under cyclonically curved 700-mb. mean
flow and weak easterly anomalous flow in the Kansas-
Missouri-Illinois area ; both types offlow have been re-
lated empirically to vertical motion and precipita.tion.
However, the explanation for the precipitation which oc-
curred in the easterly flow north of the daily Lows, along
the eastern slopes of the Rocky Mountains in Colorado
and Wyoming, is not easily extracted from the monthly
mean circulation at the 700-mb. level. The vertical mo-
tion and precipitation in these central Rocky Mountain
States were enhanced by orographic effects not reflected
in the upper-level circulation. Also, the precipitation
occurred during a few short periods which were not typi-
cal of the predominant pattern of the region and conse-
quently would not Ibe reflected in the 30-day mean
circulation.
5. RELATION OF PRECIPITATION TO VERTICAL
MOTION
Of coursa, subjective evaluation of the monthly mean
flow in terms of the average vertical motion or precipita-
tion is rather crude, but until recently, it has not been
practiaal to objectively estimate the vertical motion. Now,
the availability of operational b'aroclinic models and elec-
tronic computers enables us to compute, objectively, the
vertical motion for a midtropospheric level. The National
Meteorological Center of the U.S. Weather Bureau at
Suitland, Md., using a two-level baroclinic model, esti-
mates twice daily the concurrent vertical motion at 600
mb. from initid (observed) data.
The 30-day mean of these values for March 1959 (fig.
11) is a logical pattern roughly consistent with the con-
comitant mean 700-mb. circulation. I n general in figure
11, descending motion (negative values) is found west of
the troughs in the northwesterly flow and ascending mo-
tion (positive values) east of the troughs in the southerly
flow. Exceptions are the negative values just off the north-
eastern coast of the United States, under and east of the
mean trough (fig. 1, 11). This, at least at first thought,
does not fit the accepted relationship between horizontal
circulation pattern and associated vertical motion, but
further inspection of figure 1 reveals that subnormal 700-
mb. heights and marked anomalous, northerly flow ex-
tended from eastern Canada to New England, suggesting
that cold subsiding air masses frequently invaded the area
in question, off the northeastern coast of the United States.
Portions of the 30-day mean vertical motion were cor-
related with the total monthly precipitation (fig. 8). The
descending motion over the extreme Southwest and the
northern Plains States was related to the driest areas this
March. Prescott, Ariz., which had no precipitation, and
FIGURE 11.40-day mean vertical motion at the 600-mb. level in
millimeters persecond for March 1959. Map was obtained by
averaging the 60 available twicedaily values computed from
baroclinic modelandobserved data. Isoline interval is 2 milli-
meters per second. Absolute values greater than 2 are stippled.
Descending motion (negative) and ascending motion (positive)
tend to be located east of the 30-day ridges and troughs,
respectively.
FIGURE 12.-30-day mean of only the ascending (positive) daily
vertical motion for March referred to in legend of figure 11.
Isoline interval i s 2 millimeters persecond.Values greater
than 4 are stippled. Pattern resembles the total monthly pre-
cipitation (fig. s).
Los Angeles, Calif., reported record dryness for March.
Helena, Mont., had the driest March since 1881. The
ascending motion over the Far Northwest and the States
bordering the Gulf of Mexico fit the precipitation pattern
quite well. However, pronounced discrepancies existed in
the Nebraska-Kansas-Iowa and Northeast areas where
sizable amounts of preclipitation occurred in regions of
little or no mean ascending motion. This could result
from the averaging process where large ascending motions
during short periods of storminess would be counteracted
by long periods of subsidence. Therefore, the mean of
only the positive values (ascending motion) was obtained
(fig. 12). As expected, there was considerable ascending
motion in these wet regions. Apparently, west of the
118 M O N T H L Y W E A T H MARCH 1959
mean troughs, on the western fringe of the precipitation
areas, there were periods of both ascending and descending
motion associated with the lifting and precipitation north
and east of the daily storms and the sub'sidence in the
cool air behind these same storms as they moved eastward.
The availability of moisture, which is an additional re-
quirement for precipitation, has not been considered in this
brief investigation, and should be inchded in any further
study.
6. ALASKAN COLD AND HAWAIIAN WARMTH
an anomaly of f 3 .7 " F., almost 3 stmdard deviations
above normal.
This warmth was associated wit,h a deficit of precipita-
t,ion at both stations. Honolulu reported only 0.17 inch,
2.13 inches below normal, and Lihue had 1.37 inches, 2.70
inches less t)han normal.
TARLE 1.-Alaskan and Hawaiian surface temperatures (" P.) for
March 1.959
Station
I
M;;gly
I
Normal
1
Anomaly lbtmdard deviation
1
records Year
start
Most of Alaska experienced a record-breaking cold
March (table 1). Blarrow, Fairbanks, and Nome, well
distributed stations with long periods of record, had the
coldest March on record and Anchorage the second coldest.
Departures from normal of the monthly mean temper-
atures were as large as two or three standard.deviations,
a rather rare event. Fairbanks, with 16" F. below normal,
had the most extreme anomaly, but Barrow, with a frigid
mean temperature of 27" F. below zero, suffered the coldest
weather in the absolute sense. At the latter city the maxi-
mum daily temperature did not exceed -5" F., and the
minimum was always colder than -21" F.
This cold over Alaska was produced by stronger than
normal flow between the mean ridge over eastern Siberia
and the trough over Alaska (fig. l), which continually
advected cold air masses from the Arctic Basin into
Alaska. This was a very persistent pattern, as illustrated
by the 5-day mean trough and ridge frequencies (fig. 4)
and produced over Alaska the coldest mean thickness
anomaly for the Northern Hemisphere (fig. 5).
While the Alaskans were shivering in record-breaking
cold weather, the Hawaiians basked in record-smashing
warmth (table 1). At Honolulu, the daily maxima nver-
aged 79" F. and the minima 71" F. for themonth of Marcll.
Of more significance was the monthly mean temperatllre
of 74.7" F., the absolute highest since records began in
1905. This month's mean temperature represents s de-
parture of f2.5" F., which is large for this subtropical
station that has la standard deviation of only 1.0" 17.
Similar weather was experienced at Lihue, Kauai, where
a record monthly mean temperature of 74.3" F. proclucetl
Alaska
/I l l i
I€ au,aiian Islalkds
Honolulu ......~~~..~...~~~..~~~..~
Lihue-.-..- ....-.
~
......
----.--~.-i :%: 1 %:6" 1
+3.7
1 i:: 1 %5"
+2.5
___ *Record for March.
The dry and ext,remely warm weather occurred with
a stronger than normal subtropical ridge in the eastern
and central Pacific. Over the Hawaiian Islands 700-mb.
mean heights (fig. I), 1,000-700-mb. mean thicknesses,
and sea level mean pressures were all above normal dur-
ing March.
REFERENCES
1. 14:. M. I!allenzw~ig, "The Weather and Circulation of Sep,tenlber
3958", Monthly Weather Review, vol. 86, No. 9, Sept. 1958,
2. .T. IC. O'Connor, "The Weather and Circulation of February
1959", M o n t l ~l ~ Weather Review, vol. 8'7, No. 2, Feb. 1959,
3. J. F. O'Connor, "The Weather and Circulation of June 1 9 5 6
Record Cold in Northeast and Warmth in Northwest," Monthl,!
Weather Review, vol. 86, No. 6 , June 1958, pp. 229-236.
4. lJ.S. Weather Bureau, Clirnatologicnl Uata, Nutional Xunmary,
vol. 10, No. 3 , March 1959.
5. I7.S. Weather Bureau, Jlnily Weather Mal), Washington, U.C.,
hlureh 1959.
ti. 17.8. Weather Bureau, "Normal Weather Charts for the North.
ern Hemisphere," Technical Paper No. 21, Washington, D.C.,
Oct. 1952, 72 pp.
7. 1T.S. Weather Bureau, Weelcly Weather and Crop Rvlletiq
Xntionnl runm mar^, vol. XT4VI, Nos. 10-14, March 9, lc;, 23, 30,
ant1 April 6, 1959.
JQ,. :359-x7.
PI). 81-90.
CORRESPONDENCE
(C'ontinued f ~o m 21. 106)
We were not aware of a similar modulated technique in
use by the Weather Bureau.
We are aware that saturation thresholds are somewhat
difficult to work with, but for conditions of level plot land,
we assume that a saturation point exists and that any
precipitation in excess of this value is runoff and hence
lost as far as crop use is concerned.
During the past year we have had the opportunity to
compare: atmometers with the Class A pan, and the bnried
4-foot pan. These observations have not caused us to
alt,er our point of view on the disadvantage of pans, gen-
erally. Frost is a serious limitation to the use of atmom-
eters. (I n t h i s connection we have been experimenting
with an instrument which withstands 7 degrees of frost.)
Our co-workers in Canada have noticed time trends in
Bellani plate atmometers only when air enters the cup or
when the surface color or porosity changes because of
dirt or acc1unnlat)ed salt,s.
U S GOVERNMENT PRINTING OFFICE:1959