Downloaded 09/23/21 06:07 PM UTC DECEMBER1956 MONTHLYWEATHERREVIEW 437

436 MONTHLY WEATHER, REVIEW DECEMBER1956 HURRICANE SEASON OF 1956 GORDON E. DUNN,WALTER R. DAVIS, AND PAUL L. MOORE Weather Bureau Office, Mlarni, Fla. TABLE1.-Damage and deaths from all tropical storms and dis- 1. GENERAL SUMMARY tnrbames of 1956 The 1956 hurricane seasonwas comparatively mild Type of storm Area from thestandpoint of stormfrequency. Only eight - ~___- tropical storms developed compared to an average during 4 La., Miss. 0 Tampico, Mex. thepast two decades of ten;four reached hurricane 18 French West Indies. 9 Puerto Rieo. intensitycompared to a normal of five duringrecent 0 Bahamas. 27 Mexico. years. In onlytwo of thepast 15 years have tropical 15 Mostly in La., Miss., Ala.. Fla. storms been so few and, by 1925 standards of detection HurricaneGreta- ...~~..~ 0 Mostly Fla. east coast. 3-5. ~.~ 1,899,201 Puerto1 Rico and other and classification, possibly only three storms would have islands in Antilles. Tropical disturbance.. ~ ~ July 4-5-. ~ ~ ~ 503,000 0 Alabama. been designated astropical. Two storms reached the &uasi-tropicalstorm...~~ Oct. 15-16." 3,000,000 2 Florida. c___~ coastline of the United States, both in theGulf of Mexico. Total in United .. .~. -.~ ~. .. ~ ~ $30,007,605 The 1956 season was also mild from the standpoint of States. TotalAtlantic I..."-.-- ..... I$67,836,806 I il I tropical stormintensity. One of thestorms was of hurricane area. I I/ hurricane intensity for only a few hours, Flossy was of *Zero indicates no deathsreported. full hurricaneintensity nomore than 24 hours,and hurricane Greta was asmuch extratropical as tropical storms and there was never any definite center or eye. during her lifet,ime. Indeed only Betsy appeared to have The temperature aloft over the surface Low remained as all the characteristics of the classical hurricane and even cold or colder than the surrounding air." The situation this storm did not increase in intensity andsize in accord- in the high troposphere was also markedly different from ance withstatistical expectancy. None of thefour that usuallyobserved duringhurricane formation. At hurricanes of 1956 couldbe classified as severe (120 to 250 mb., at 0300 GMT on the12th, an intense cyclonic 150 knots sustained wind). circulation was centered southeast of Fort Worth and at Tracks of the tropical stormsof 1956 are shown in figure 0300 GMT on the 14th this center had moved almost over 1 and death and damage data are tabulated in table 1. the tropical storm in Louisiana. 2. INDIVIDUAL STORMS The highest wind reported ashore was 55 m. p. h. from the east at Grand Isle, at 0715 CST on the 13th. A boat Unnamed Tropical Storm, June 1l-ld."This was the 5 miles sout'h of Pilottown,La., reported gusts to 60 second tropical storm to occur in June in 10 years. On m. p. h. from the south-southeast. The lowest observed June 9, a fracture occurred in the polar trough lying just pressurewas 29.66 inches at MoissantAirport, New off theAtlantic coast, and t'he southernsection began Orleans,and at McComb,Miss. The highest measured moving westward across Florida into the Gulf of Mexico tide was 4.7 feet above mean sea level at Biloxi, Miss. whiletEe northern section continued eastward over the The heaviest rainfallwas within 100 miles of and to the western Atlantic. The westward moving southern section east of t'he storm track and decreased from 6.13 inches at apparently induced an easterly wave which moved across Grand Isle, La., to 5.60 inches at Monticello, Miss., 3.17 t8heextreme western Caribbean, western Cuba, southern inches at Jackson, Miss., and 1.60 inches at Greenwood, Florida,and the Yucatan Peninsula, and on the12th Miss. The benefit to crops from these rains, which ended formed a depression in the Bay of Campeche under the a drought at least temporarily, exceeded property losses mid-tropospheric trough. The disturbance moved north- from wind and water on the coast. ward,acquiring tropical storm intensity and the center Four persons were drowned, three of them when a tug crossed theLouisiana coast a short, distance west of sank off the Mississippi coastand the other, a truck Grand Isle during the late forenoon of the 13th. Accord- driver, when his truck skidded on the bridge over Lake ing to the report from t'he hurricane forecast center at New Orleans, "The storm had both tropical and extra- Pontchartrairl and plunged into the lake. The bridge was tropical characteristics.Rainfall was tropical in nature damaged by the truck but moreseriously by a loose barge. but neverformed inbands characteristic of tropical The total damage to the bridge was estimated at $12,000. Unauthenticated | Downloaded 09/23/21 06:07 PM UTC DECEMBER1956 MONTHLYWEATHERREVIEW 437 FIGURE1.-Tracks of hurricanes and tropical storms that occurred during 1956 in the North Atlantic Ocean. Tides generally ranged from 1 to 4 feet above normal sion intensified to storm intensity on the afternoon of the along the Louisiana and Mississippi coasts. The Freeport 25th. Sulphur Co. suffered some damage to their sulphur mines On the morningof the 26th, Navyreconnaissance located near the coast' south of Houma, La., where the tide was the center with lowest pressure 991 mb. (29.26 in.) and 4.5 feetabove mean sea level. Minordamage to the found maximum winds of 50 knots in the northern semi- beaches, small boats, and piers occurred along the Missis- circle. Early that evening the center moved inland south sippi coast in places where tides were said to have reached of Tampico, Mexico where a maximum wind of 70 knots as much as 5 feet above mean sea level. The total dam- (81 m. p. 11.) was reportedwith lowestpressure 29.60 age from this storm is estimated at $50,000. inches. It is thought that winds of hurricane force existed HurricaneAnna, July 25-26.-The easterlywave in only for about three hours as the center approached and which Anna developed passed through the Lesser Antilles crossed the coastline. on July 20 and continued westward through the Caribbean. Many houses in the poorer sections of Tampico were Instability of the wave began to increaseon the 23d as the blown down and some roofs of the better homeswere wave, extending on the surface from central Cuba to Pan- blown off. Although only 2.5 inches of rain were reported, ama, passed under a very well developed anticyclone in downtown streets in Tampico were flooded. There were themiddle and upper troposphere. A weakcirculation no reports of deaths or injuries. Damage has been esti- may have developed as it moved over the Yucatan Pen- mated at around $50,000. insula on the night of the 24th but all surface winds were Hurricane Betsy, August 9-19.-The general circulation under 20 m.p. h. Intensificationwas steady after the over the Atlantic during most' of the hurricane season of center passed into the Bay of Campechr and the depres- 1956 and its possible relationship to the mild hurricane Unauthenticated | Downloaded 09/23/21 06:07 PM UTC 438 WEATHERMONTHLY REVIEW DECEMBER1956 activity will be discussed later.A temporary break in through the central Lesser Antilles about midday August the prevailing circulation pat'tern occurred earlyin August 11. It crossed over the island of Marie Galante and be- as the Azores-Bermuda anticyclone moved northeastward tween Isle des Saintes and tlle extreme south portion of for a period of about a week and intensified while a trough Basse Terre, Guadeloupe. Reports indicate 18 lives lost extended through western Europe. Similar patterns have and severedamage. On Guadeloupe, 1,000 dwellings been noted previously [I] as antecedent to hurricane for- were extensively damaged, all communications disrupted, mation.Apparently the injection of cold airaloft and and 50 to 60 percent of the banana, breadfruit, coconut, cyclonic vorticityinto the Tropics by a meridionally- and papaya trees destroyed,a serious blow to the economy extensive trough encourages the transformation of st,able of theisland. The banana crop loss wasestimated at waves in the easterlies, and even in the intertropical con- $3.5 million and preliminary estimates give$10 million for vergence zone, into unstable waves and eventually into the total damage figure. Winds were estimated at 100 to storm circulations. Around August 9, when the develop- 120 m. p. h. on Guadeloupe and the lowest) pressure was ment of Betsy wasfirst suspected, the ant'icyclone had 991 mb. reached maximumintensity and immediately beganto After moving through the Leeward Islands, the hurri- subside and to return to its previous position south of its c'ane began a more northwesterly course, passing about30 normal location. miles south of St. Croix, Virgin Islands, and reaching the Lack of reports in the eastern Atlantic, makes it'impos- southeastern tip of Puert'o Rico in the early morning of sible to arrive at a detailed analysis for the period preced- August 12. Priorto reaching Puerto Rico the storm ing the first indications of this storm but there was some displayed a small but apparently real oscillatory motion evidence of an easterly wave near longitude 33' W. on about the mean track with an amplitude of a little less August 6. Extrapolation at' a normal rate of movement than )i degree and a period on the orderof one day. The would have brought it to the vicinity of 50' W. on the oscillation was sufficient'ly definit'e that, some forecast use 9th. On that date the following report was received from could be made of it, on an ext'rapolation basis. Following the M/T Marisa: "At 1218 GMT passed through t,rough of the turn to a more northwesterly direction, thisoscillation tropical storm in position 14.05' N., 55.25' W.

Load more