JUNE,1922. MONTHLY WEATHER REVIEW. 295 Kbppen in Bsrtholomew's Atlas, which in turn were are dated as to month, though not as to year. Koppen's eralized from Meldrum, long director of the Mauritius tracks are dated only as to season, November and Decem- Kservahry. "he wider lines indicate that three or ber, January to March, and April to May. more stony followed approximate1 that course in a This chart and foregoing data lend little support to the 35-year penod. The numeral at tie end of the line oft-repeated genera.lization that tro ical cyclones origi- indicates the number of storms along that track in that nate in a few restricted areas on t e western sides of eriod. Koppen's charts have been combined and modi- oceans at, the time when the doldrumsR are farthest from led to aid in legibility and have been supplemented by the Equator. Many o ther widely accepted ueneralizations several notable tracks shown in Ein Atlas fiir den In& as to tropical cyclones a pear unsafe in tze light of the &en Ozean, Deutsche Seeciurte, 1891. The latter tracks fuller data being gathereT; . TROPICAL CYCLONES IN THE NORTHEAST PACIFIC, BETWEEN HAWAII AND MEXICO. By STEPHEN S. VIBHER. \Indiana University, Bloomingtan, Ind.) Reaeld, in his paper on cyclones of the Pacific, forming List 0~ tropical mjclonic stoma in the northenst PaciJc (west of MeTicoaad a psrt of Co-odore Perry's Narrative of &.pQditioll to , ('ealrul dnuricaa)&deast of the longitude of the Hawaiian Islanda-Con. Japan, devotes six pages to the northeast Pacific,' and presents a chart showmg the approximate tracks of 13 cyclones most1 in the region just west of Mexico, but Year. Month. - Source of Information. partly near Jawaii. In the Segelhardbuch -fGr den North West Stillen Oze.anz there is a list of 45 storms occurring in that mgitude. region between 1832 and 1893, no mention being made - however. of those described bv Redfield. lS5.5 ...............June .............. 20 105 Redfleld. No mention of tropical cyclones occurrinu in this 1s............... Aug.S-6 .......... 1s 1W n. S. H. region between and has conie to ligyit except 1S:S ............... Aua. S-9 .......... 15 I 117 Bedfleld. 1892 1915 1% ............... Bept. I ............ 20 I 1'22 Hedfleld. that the courses of Six are traced by HurdSJ IS57 ............... JuneW ........... 11 110 D. S. H. 1s;............... Sept. ti ............ 19 121 D. 8. H. Severe storms occurring in September, 1915 and Sep- 1SS.. ............. -4ug. 17. .......... 13 11.5 D. S. H. lSi.5.. ............. Nov. 21.. ......... "1 174 D. 8. H. tember, 1918, are described in the MONTHLYWEATHER lsis ............... dey t .............10 16 w D. 8. H. lyii ............... Ju v25 ........... 10 109 D. s. H. lS70 ............... June 17 ........... 16 1% D. 8. H. Since August, 1921, brief mention of four tropical lii0.. ............. Sept. 21-24.. ...... 17 141 D. d. H. 1,571 ............... July3 ............. 16 117 D. 9. H. cyclones haa been made in the same journal? lg74 ............... Nov. I9 ........... lti 161 D. P. H. The followin list includes the 70 storms mentioned in ls77 ............... Nov. 5 ............ 14 1'& D. 8. H. l!W ............... July6 ............. zu rm D. Y. E. these sources of information: 1.W..............., Ozt. 13 ............ I 18 111 D. e. H. I&. .............. July 3L.. .......... 13 118 D. 8. H. List o tropical yclonic stornis in the northe(i8t Pari c (west of 3iurii.o nwl IS* ............... 1 Repl. 7 ............ 14 105 D. 8. H. Cf,itral Amerira and cast oj'the lottgitide <$the aicniiati Islatwis.) IW.. ............_I Yept. 21-33. ....... 3u lo5 D. 8. H. Q ASS*. ............. 01%.3.. ........... 23 108 D. P. H. ISM.. ............ .I Xep1.W ........ 17 107 D. 8. H. IS*. ..............! Oct. '33.. .......... 24 107 D. P. H. Place of origin, or 1sIi5 ............... July31............ au 130 D. S. H. I 6rst record. 1s............... Sept. 12 ........... I m D. s. H. Month. --- Sourre of information. 1s: ............... Oct. 5-6 ........... ?A 108 D. 8. H. Pear. IW............... Oct. 25 ............ 1uB D. 9. H. North West 1W............... Se t 18 ........... 2 95 D. 8. H. 1 I latitude. longitude lSi ............... Ju& 3u 114 D. H. I ............. S. 1x37 ............... I Out. M ........... li 1Ui D. 8. H. 15 Ell D. S. H. l&%. .............. Aug. V3-14.. ..... .i 1" 1% D. a. H. 1832.. ............. December.. ....... 13 1s D. S. H. 1YW ............... Sept. 10-11 ........ 17 106 D. S. H. 1- ............... Nov. 1 ............ 23 106 D. S. H. IW............... Bept. W ........... 23 107 D. 8. IE. 1840.. ................. .do.. .......... "2 105 D. S. H. 1,SgQ.. ............. dllg. >3*. ........ 14 122 D. 8. H. iM2 ............... October ........... 15 93 D. S. H. 1m............... lug. 18-19.. ...... 16 l2.I D. 8. H. 1e4a ............... sept.23 ........... 13 13Y Redfield. 1S1 ............... Aug. 2 ............ 1G 11s D. 5. H. 1S47... ............ Oct. 24 ............ 17 Redfleld. 1w1 ............... Aug.7 ............ 11 10i D. 6. H. 1W............... JuneZ1-22 ........1 16 110 Redfield. WXZ ............... July 19 ............ zu 1 li D. R. IT. 1850.... ................................................... Redfield. 1902 ............... Dec. 234011.2..... 21 15s Hurd. 18jg ............... June% ........... 16 10i Redfield. 1904 ............... Nov. SDm.4 .... 18 161 Hurd. 1850.. ............. Aug. 5.. .......... 11 b 117 Redfleld. iw ............... DW.23-30 ......... 15 1.56 Hurd. 1850.. ............. Sept. 9-11 ......... 15 IW Redfleld. 1W............... May 3-10.. ........ I2 151 Hurd. 1850... ............ hut. Z........... 26 123 Redfleld. 1w16 ............... Oet. w ........... 1s 154 Hurd. 1850 ............... I oct. 14........... I 18 Redfleld. 1- ............... Nov. 8-13.. ....... 20 157 Hurd. 1850............... I oct.3............. I 14 c117 Redfield. 1915. .............. Sept. 4 ............ 15 110 M. w. R.,a;*. 1850.. ............. October ........... 17 105 D. S. H. 1918.. ............. Sept. l%lti..-. .... 18 105 MWR 46'-568 1851 ............... 15 1'10 D. S. H. 1921.. ............. Sept. 24-30 ........ % 105 M' W' R" 491-518: 1851 ............... 21 107 D. S. H. lWl.-. ............ Ort. 4............. 22 158 M: W: RY ,49;-579. 1851... ............ ............ Redfleld. 1921.. ............. Oct. 9.. ........... 17 102 MWR 49:-581. lsSa ............... July 16-19 ......... E :::: D. Y. H. 1Y2............... Feb. 1 .............I-. ........ ........ M: W: R:: so;*. 854 ............... I Oei.5 .............I 28 135 D. S. H. I I a NNE. b N.-W.4. I NE.-NN W.-WN W.-Y W. Fm # SE. c 8W.-BE.-E.-N.-W.-S W. b W E. Hurd: Article Cyclonic storms and typhoons north PsriEc. 8. d BE.-NE. Of the u. eRODlN. Weader Bureau, Januarj. March, and April, 1913. 1 Willlam C RedBeld: Vol. I1 1858 Ben. Doc. 79, pp. 354-359. D&he 8warle Hamburg' 189i p. 309. The monthly distribution of these storms is shown in a Wlllis E. Hurd: byclmlc st&mn hnd t hoona of the north Paciflr artirle on the reverse of MetWtOlo 1 Chartd oj the Wrt~Pnrffrc,U. 9. Weather E&eau, January, Table 1. All but two have occurred in the six-month IU8rcl1 mdA ~1 l!!? period June to November, inclusive. September with 'J. f.Kim& A Pw1P.c hurrleane of Saptember 1915' Mo. WEATHERREV., vol. 43, p. 4$& and F. Q. Tingley: Tropical cyclone of Beit. 1&17,1918, Just west of Mexico; 3s per cent is the stormiest month, but October with YO. WEATHeS REV Y' Ml3. * F. Q. Tlngley, MS. WEATEEB REV., 4% 518,579,581; and I; 99. 25 per cent is only slightly behind. Unauthenticated | Downloaded 09/28/21 05:25 PM UTC 296 MONTHLY WEATHER REVIEW. JUNE,1929 TABLEl.-Monthly distribcctwn of the foregoing stomur between Hawaii Table 2 indicates the approximate area of origin or of and Central Anwrku. htreport of these storms. This table is a revision of the one by Schiicke While he studies only the 45 storms listed in the Segelhaiidbu.ch, here GS storms are considered, c) ~ two of the 70 storms given in the foregoing list not being Numbei..... readily located from information at hand. Per rent of total ....... 0 1.6 0 0 0 Figure 1 shows the approsimate courses of about 60 I tropical storms in the region under consideration. These TABLE2.-% ical yebikes of the nmtheuat Poci +Region of origin tracks were obtained from the several sources (l), the or first reeorJof storm for 18$+19Jp, elassijJacoorc+ing to iiioiiths chart by Reclfield,' (2) a chart in the Segolh~dbu,chfiir aid 50 squarcs. den. Stitlen Ozean.8 (3) A large number of the tracks were copied from the official German atlas of the Pacific.g (4) Several tracks are traced on Monthly Meteorological lo .... Chart,s and Pilot Chsrts l1 for the North Pacific. (5) ..... Several recent triroks are from the MONTHLYWEATHER REVIEW, especially those for 1915, 1918, and 1921. June..... 10-15 .............. 1 15-20 .......... 2 .... 3 Table 2 and especially the chart of tracks indicate that most of the recorded storms occur in longitudes 100' Total.. to 130° W. and latitudes lao to 27' N. However it is July..... .......... not improbable that the entire area here shown is occa- ........... .... sionally crossed by tropical c clones. Certain it is that ....... .... S even in the midst of the large t lank area between Hawaii Aug ..... and California gales are not lacking, although some such gales are due to steep barometric gradients on the side Tolal.. of the Pacific high-pressure area rather than to local sept ..... storms. However, most unusually steep gradients of .... this sort are closely related to cyclonic stom near by. Total.. ..... .... .... As to the courses followed by the storms: The chart Oct ...... 10-15 1 j... ............ 1 ..................................... 2 indicates that most of them travel northwest or north ...... 2 a .... ............................ 9 ....I:.. ... in this re ion. However, a number have recurved and 3-25...~ ....... 5 1 ................................ 1.. .... 7 25-30..:_-_-__ -_____1 ...................... -_ 1 progressef varying distances toward the northeast. One, Total.. ..... 1 I._.