-408 MONTHLY WEATHER REVIEW. AUGUBT, 1917
between the limits +ZOO and --20°, EO that we don't poesess its cor- rections for lower temperatures. In order to reduce the alcohol thermometers to the tcrmy oE the inter- national hydrogen thermometer, to all readi made on alcohol ther- mometers, before their being published i n x e Annals for lS!E, cor- rections were ap lied. aa they were obtaincd by Mr. Hlaaek from com-
tory, with the norm:il therruometer Tonnelot. purc-lnsPd I r v the O11~erv- rtory and verified in the Internatinrial I3iire,ui nf Wei-l its and 3rp:ie-
urea. The corrections were-
parisone- of the t P ierrriometer. Geissler Yo. A. belonging to the OLserxk
From direct cornpsrisone of tlie readiiigs of the ahJho1 t.hermometers with those of the mercury onefl, made at several stations in the district of the Ob*rvatory in t.he interval -30' to -40" it follows, that these corrections ought not have heen a plied to t.he alcohol thermometers on most stations. for the radings orthe alcohol thennometers differ iii
the abovemeiitionecl interval i n general very little from tlie renl!ingw of the mercury thermometers. Therefore since 1893 tlie above-stated crorrectiow were i i o uiore applied to the readings of the alcohol thermometers :iiid for low temper- atures only additir~nd c0rrectio:is were nsed. obt,a,ined froin direct crompariaons of the alcohol thermometers with the mercury OIICP,
belonging to the atat.ions. Owingto these re~soiis I suppose, that the correctiiiii -2.0' C. ehuulal not have been applied ta the reuliiigs of the alcohol thermometer 5). 81*, in Verkhoymek iii 1393: as we do not know the tnie currectio~s for the thermometer No. Sl* in the interval -30' lo -50'. it wnultl be more appro riate to use its tlirert rcadings withwit s:iy ;t:l.iitional correction. !l& lowest tcmpetzwe of air in Vcrkho ctn8k ought thiwj;)rc
to be considered a8 -68' C [-90.4O F.], it U also tk lowrst tcttiprrflltm which haa ever been obserwd on the sfntioi~s of our nwteorvlogical tit.1.
As for the value -73", which Prof. VoeikrJv gives in hie work, i c i n most probably due to B misuiiderstmding; i t seems, t.hat he iulilol the correction -2.0° once more to the alredy-corrected reading of the alcohol thermometers, pnblighetl in the Annals of t.he Obaen-atmy fin
the year 1892. Yours truly? [Sikmed] U . GALITLIN.
SS/. 5a4 c 7 Y F
NOTES ON THE HOT WAVX I N SOUTHERN CALIFORNIA.
JUNE 14-17, 1917.
By FORD A~MMAK CARPENTER, &feteorolugist.
ID3k.d: Weather Bureau. Los Angeles, July 12,1917.1
Record June temperatures were experienced enerally
17, 1917. As this heat wave was uni ue in the meteoro- logical history of this section of the 8nited States, both in its distribution and effects, some notes have been col- lected on the sub'ect and rn here presented for future
Con~Wiw camea of hot .waves in southem California- Mr. G. H. Wihon @ves the following explanation of hot, waves in California.'
In the late s ring, summer, and early fall, when HIGHB cover the North Pacific &ates 3nd Plateau region, light to moderate, north to
eaet winde revail wer California, and the cool ocean influences are checked or feld back. The sky is clear and insolation is great, and the air ia heated dynamically in moving down the mountsin slo es, callsing very high temperatures in the valleys end m t sectims. h e n these conditione are very marked they produce hot waves.
in southern California during the four days en c f lug June
reference and stu d y.
1 Weather Forearsting in the United Statas, Washington 1016. p. 33% (W. R. No. 588.)
And the present writer, in discuss a hot wave which occurred at Los Angeles on Septem Y er 17, 1913, gave t-he following explanation:
ell, like all instances of tem eratures above 90° in this ortion of aouxern ('alifornia. was a welldelned "norther" condition Eronght about by preesure distributioii typical of mch phenomena. On Septemhrr 15 tlie barornptric ressure was high over the Nortli- west and low in the Southwest. Whxe the low area remained stationary for many dap. the high area l~rogressed in a southeasterly direction. The greatest difference in pressure was coincid~nt with the wariiiest clay, when the weather n1.i showed a ,gradient of a tenth of an inch in ~iarometric pressure to tile Runtlrod miles on an east-antl-west line.
Gtn.Eml wcnthur. eoiulitions ncrompamyinq the hot ~~~~v t .- T h e hot wave of ?Juiit?, 1917, ext.ended over a period of
four days; tlie Gryt indication that a eriod of warm
vf t,he 1 Ith, wliich showed the arrangement of hig and low u r (w t,ypicul to such condit.ions. datc tiic seasoil bad hem backward, the
coo1 uiid cloudy. Tiw cnsuing wceli brought a rapi balancing of the tcmpernture deficiency which was of long stuncling. At. Los Angdos the temperatme rimelied
looo twice in the four days Juiie 14-17, with t,he maxi- muni of 105' on tlia 17th. (See fig. 1.) The highest. t.em wraturc of whirhwc. Iiare data, 134' E"., was registered
at- decca, Itiverside County, on the 15t.11, and the lowest maximum, S i ' , occurred at Yan Diego. Except along the. immediate coast section t.he mean maximum tem- pcraturc? for southmi Cnlifornin for tlic four days
ap roximated 100'. Lutlicni California is spncially fortunate in having
a number of s t s t h i s equip ed with t.hermogra~lis. I n perusing the thermograms f rom 16 stations it is found that they fall int.0 two general classes: one (illustrated by Sg. 2) where the crest of tho hot wave was reached on the fourth day; and the other (see fig. 3) where the t.emperature suddenly touched the highest point on the first day and thereafter steadily diminished. Amon sta-
tions falling in the first class belong Los Angeles, sasa-
dena, Mount Wilson, Redlanda, Riverside, Corona, Upland, Pomona, Sail Brrnardino, and Saiita Barbara. The second class includes San Diego, Escondido, El Cajon, Bonita, Tustin, and Whittier. Incidental phenomena were associatt?d with the hot wave. The iuflucnce of the hot wind a t midnight of the 16-17tmh (sec fig. 4), which traversed the seaward side of the mountain range and caused tlie temperatur? to
rise 15 degrees, is shown at El Cajon, San Bernardmo, and Redlands. This hot wind was also felt st many of the desert stations farther south. Another accompanying henomenon was the effect of the neighboring forest L e s on the otherwise e uable littoral weather of Santa Barbara (see fig. 5). Ipecial meteorological observer G. W. Russell at that station is probably correct in at- tributing the abnormal temperatures there to the forest &e. Concerning this phase of the hot wave Mr. Russell
says :
The cause of this hot
T ""E
weat.iicbr was immincvit occurrcd with t P le weathc
-
The Septemlrer hot wavein Los AngeJes, Cal. MONTHLY WRATHHER REVIEW, Wash- ington, Sept., 1913,41:1404.
409 A~GIIST, 1917. MONTHLY WEATHER REVIEW.
FIG. l.-The.rmogram recorded at U. 8. Weather Bureau, Los Angeks, Gal., June
Similar records at Mount \Vllson, P d e n a , and other stations withln 25 miles o: illc
shore show the same general characteristics.
14-17, 1917.
FIG. !?,.-Thermogram recorded at Rlrerside, Cd., June 14-17,1817.
Similar records at Coma, U land, Pommr, and the gwater portion of the ritrus dlstrict show the same general Cthactcristies.
FIG. 3.-Thermogram recorded at U. 8. Weather Bureau, Slrn Diego, Cal., June 14-17, 1 P l i . __-. .
This curve, with its maximum temperatures on the 14th instead oI.the !74h, as else- where in aouthern California, IS also chamterrstlc of Kscondido, Tustin, 11 hittier, and Bonita, although these statlons regktered much higher temperatures thm these at 8an Diego.
FIG. I.-Thermogram recorded at San Bernardlno, Cal., June 14-17,181'1.
Note the effect of the northeasterly wind about midnlght of the 16th-17th. Similar eflects were recorded at the same hour at Redlanda and at El Cajon Ban I iego County; El Won, i s about 90 miles south of San Bernsrdino and a Uttlebver 10 milesnorth- east of Ban. Diego.
*+
J."Cli.1117 . i. .'.:..,!'....:
FIO. &-Thermopl.am recorded at Banta Borbsnr, W., June 1447,1017.
Note the d i s n r r a n y t of the daily temperature march due to forest flres burning cvlthln a few miles o the rtatim. Once before, In t h e y t bo yeam, hm SOnta Barbare had such hlgh tempmtum, slro In cosmectlon altb Os& f@eL
yt If my memo ia to be credited, this is the second very hot [luring my life?kre (Santa Barbara, Oct. 15, 1867 to June 22, 19 7), the f i a t spell was about the same hme ae the Chicago fire (Oct. 9, 1871), when this valley was burned over and considerable damage WB$
done to growing fruit, etc. [On that occlraion] apples were cooked on the fire side of the trees, beans an? other vegetables were 80 severely hurnerl that they dit1 not ow agani. Birds were often noticed to fly iiitn dwellings to get relieyfrom the heat. One saloon keeper said a little bird 8ew into a pitcher of water on his bar and nearly drowned
iii its effort to get water. As there were no instrumenta in use here there \vas no meam of accuratelv stating the temperature. I do not remember that any strong wind accompanied that hot ell. Two
two dags' heat, but started running again Boon after. This lost hot spell was gratly augmented by very Btrong northeast wind I)lowing over the forest fire directly tomsrd this a t y . Many gusts, I estimate, reached a velocity of at least 40 to 45 miles per hour. Of courae the anemometer waa not ca able of recording such a veloc- ity..l As to the temperature .of the cty unaffected by the fire heat, woiild a y that very near this clty the temperature necrr the beach
:b u d whek the Winch from the fire did not affect the temperature,
WW iwt iiniisiially Ligh, MV about SOo to 85O. The ocean water tmqierdtiire was IllJt appreciably raised beyontl tIirt of odinary sum-
mer i!nys. Swimmers mid that it seemed eveii c-nltler than usual, 80
they pluiiped iu very carefully. Tlirre havc been very man hot spells here during my 50 yeam' ritsideme, 2nd foiir yemi ago 1Ke record showed a temperature of 108", which I think is the highest ever recorded, up tn thnt time. Saturday, June 16. 1917, forest fir- were burning at many pointa around us here, and the direction of the wind WM such aa to bring the h a t directly across this depression. For some unexplained c a m the growing crops, unless walnuts, were not materially affected. and it ia believed the bema mill entirely recover with the fogs and be very
little if any worw for the heat.
permanent streams, never before dry, were entirely dry s c iiring the
EJect o j the h.ot wx~ve on vegeta.tion.
Press coinments on the hot wave.-The California Culti- vator of June 30 said:
* * * Some lemons of nearly icking size were actually cooked %:id t.he tissue immediate1 broken fown. Others had when cut much the same appearance as k t e d lemons. Valenrias were softened 80
illat picki!ig ceased for Revera1 days. They are now retunling to nor- inxl condition and shipping is resumed. Walnuts suffered greatly, a
hrge number most exposed to t,he afternoon heat being burned BO that they dropped from the trees. The more pintected nub, however, are yet apparently all right. * * But, with the lo^ there are some compensations. For instance, one very 1:Uge orchard company reports t1ia.t. the heat. has wiped out prac- t.im!!v a11 R1ac.k scale from ita trew. 'l',+ lexnm injury is far less serious than would a pear at f h t thought. ;vine-tenths of t.he lemon crop for the season R as been har-
vested. Of that relnrining on the tree, the later fall picking, which ustially cornnia~ids -good xices. wlll yet be marketed. It mas feared
at first tliat these iindw h a i z e d lemons would dro 1 from the tree, hut. the drop has irinc~~l much less serious t.han at B rat anticipated.
and. unlike the fuh-giA i i lemon, the young fruit wems to how leee l i r d i n g down of t.hr? tifisue and leas in-iiry. Savel oranges in circ+ards on verv ligfir. sandy soils. and which p k - I-114' were suftcrii~ for moisture. 11:i~e diown very severe dropping. IJthrrs. es )cci:illy where well irriyted shortly Lefore t,he heat, are yet carrying tke grcat.er proportion of tlieir crop. yoii:ig fruit of valenclas, 1.ha.t is, the crop for uest year. shows much lem /*;:t a c t . of heat than doea 111e navel.
;\s to the walnut. cmp. very th3rough ~'antn\'aur! of the situation has llem made by the ('aliiornia Walnut (iroxexs' .4~.qwiat,ion. and the fol- lowing not.ire is being sent to the trade: "Southeni c'alifornia lim es erienced the hottert spell of weather reported for fortg-odd years. Enring the period from June 14 to 17,
inclusive, temperatures ranged from 111O to 123' in the shade in the
principal walnut-producing district,s. This freakish spell caught the walnuts at a very tender stage before the shells had hardened, and siinply cooked a large pefcenhge of them. We have 'ust completed a very thorough investy.atlon of the damage with the !ollowhg resultw Santa Barbara c-'oimty 5 per cent damage, Ventura County 20, & Angeles t.'ounty 25, Orange c:oiinty 35. "As the lar est productions are in Ormge and Loa dngelw Counties, the average &nap f.:r the entire crop is clme to 25 per cent, but IU
we had a prospect, ic::. the greatest roduction on record. we will atill apparent1 shi about aa many w;%uta prr were marketed laet year.
* * * h e Eel confident that .ou! prediction of +e d a m w will prove sufiiciently high and that It 18 as accurate as it ia m b l e to obtain."
-
: C M c m of Instrument no! Uo'RII to the Editor, and not recorded In the cllmrto- loghl Dlrilon, Weather BurrsU.
410 MONTHLY WEATHER. REVIEW. Amm, 1917
1b
'F.
54
115 69
101
106 56
-
97
95 70
Strawberria and 9th- emall fruits suffered from injury to ripening fruit, but young fruit IE now cormqg on and the market m abundant1 supplied. Potstoea and beans lacklng in moieture at the root suffered: but the great bulk of the crop ia in fine condition.
Summarizing the effect of the hot wave on farm prod- ucta i t is generally conceded that the most serious loss will be the navel orange crop, which in some sections is almost a complete loss. Other varieties of oran ea were not seriously damaged. Lemons were injuref in in- stances where a considerable amount of mature fruit was on the trees. Much of such fruit was burned while hang- ing on the trees. Fortunately the greater part of the lemon cro had been icked prior to the penod of great
heat, so $e damage P oss is confined to autumn lemons. In this connection it may be remarked that lemon trees are continually in blossom, bud, and fruit. The citrus trees, as such, were not injured. Walnuts had a splendid
setting prior to the heat wave, and, while the loss has been considerable, it is believed that the net gains this season will exceed those of last year. Garden truck with-
stood the heat very well; only early tdmatoes were seared; in one district a crop of tomatoes valued at
$50,000 became a total loss. Had the heat wave been preceded by several weeks of normally warm weather, vegetation would have accustomed itself to the steadily increasing temperature, but the suddenness of the mount- tem eratures and the steadiness of the drying winds
% o owe a too closely upon months of cool, moist weather. 0bservcr.t~On~ nt ilAwn do.tP porth..-At the United States coo erntire date gnrden at Mecca, MY. Bruce Drummondj the official in charge, states that followin the high teniper:iture of 124OF. on June 15,1917, IL win averaging 12 miles per hour began a t noon and continued for five hours. The relative humidity during the period between i2noon and 5 p. m. nvem ed 6 per cent as deter-
was desiccating in the estreme, burning up both vine and mot in the vineyards; but i t did 110 h a m to the dates. One unirrigated date palm decreased 6 millimeters during the drying wind but within 21 houis regained its former
diameter. Drummond also states thnt observations showed that the wind frequen$ly seemed to come in ver- tical gusts and that the vineyard was burned in spots. An interesting feature durin this hot spell (which ex-
date farm has been in esiatence) was that t e electric fan did not seem to alleviate the distressing physical effect of the heat.
C h p r i s o n with previous hot wa.wR in. scnctkrn O d i f m k .
Table 2 gives n comprehensive iden as to the fre uenay anddistributionof heated termsin this district. AI 8l ough the records are from one station only (Los An elea), they
tions south of the Tehachapi Range and 8 little distant from the coast. Lenvin out a consideration of ph sicnl
the late spring or a t the beginning of summer months that damage to farm products oc.curs. There is no doubt but that the hot wave under considemtion was the most, damaging to fruits and nuts ever esperienced in southeni
,
5
mined by a sling psychrometer. B e states that this wind
K
ceeded ail others in severity f uring the 12 ears that the
may be taken as indicative of general prevai pi ing condi-
discomfort, it is only w % en the hot spells occur &ring
California. The closest previous ological conditions which occurred on June 24-28,
temperatures a t h s Angeles were 9 5 O , 9 8 O , looo, and 90'
F, respectively. Tradition has i t that the spring of 1820
also saw damaging hot winds which destroyed grain and pasture.
-_
17
OF. 9 3 9 4 67
118 70
105 6 5 6 0
103 61
........... ...........
106
6 8 6 9
........... ...........
98
70
TABLE l.-Highcet and l o w t tempcratura at rtatioM in toutlffn CaliJornk M n g the hot wava of June 14-17,1917.
e . .- - ! Dstea.
-
{H S l :: ...........................
-
%.
lg
-
I S
'F. 89 64
114 65
101 68
103 59
123 83
99
8
1% 83
94
68
118 66
107 82
112 55
111 66
114
a
112 67
105 67
77 62
97 60
105 58
109 81
-
-
108
80
115 53
113 64
118 67
114 68
106
103 57
111 63
113 71
117 61
114 73
117 67
116 73
116 6 3 6 6
8 2 8 5
8 0 8 0
9 4 9 6 5 2 5 5
111 80
115 71
TABLE Z.-Honthl and annual distribution of tempmaturea of IOOQF. andovcr at Lo8 Angelm, Cal., 1877-1917.
Yesr. ! Apr.
! ... .... _. .... - I
OF.
1878
1881..
............................... 1879 i
1882 I 1888 ...............I ........
~~ ~
May. June. 1 July. I Aug. Sept. Oct.
__ ___ - __
OF. OF. i-iy OF. OF. -3'.
....................................................... 103 ........ 1
................ ........ I
....................................................... I 100 ........ 1 b
100 I lcn 2
a104 * 101
........ .............................................
100 100 ................ l b f 1 0 4 ........
............. !........I ........ ........................
1895.. 1896 I 103 I lsss ............... I ........ I
1905 ...............,...._._. i I
! 1
................ 1:::: .................... ! ........................ i ................ 100
................ ........I 101 ................ 1
100 ............................ 1
1
1906 ............... I ........ ! ................................ 105 ........ 1907. .............. ........ ................ -0108 ........................
1910 ............... .............................................. 1912 100 ........ 1913 ................................ 101) ........ 1917... ........ * I05 ................................
Number.. ......... 0
........
... __
1
8
t 1 1 1 0
Y