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THE HURRICANE SEASON OF 1957 PAUL L. MOORE AND STAFF Weather Bureau Office, , Fla. 1. GENERAL SUMMARY winds of 45 knots. However, over coastal areas all strong winds were on t,he east side of the storm. Exposed places Eight tropical storms developed in the North Atlantic along the coast from Sarasota to north of Cedar Keys, and in 1957 and three of these reached Fla., experienced winds of 40 m. p. h. or more and tides hurricane force. The normal for recent years is 10 storms 2 to 3 feet above normal with some damage. The storm with about 5 developing into hurricanes. The pattern of weakened as it moved inland but set off an active frontal movement (see fig. 1) was similar to that of 1956 with wave after moving off the coast on the 9th. Late st.ormsstriking the Gulf coast but sparingthe eastern on the 9th when the storm became extratropical off the seaboard as those inthe Atlant,icrecurved offshore. Atlantic coast, ship reports indicatedwinds up to65 knots. HurricaneAudrey, which strucknear the - Exceptionally heavy rain attendedpassage of this storm, Texasborder in June, was one of the most destructive particularly in Suwannee and all adjacent counties; 48- June hurricanes of record and the first to occur in that hour amounts of nearly 15 inches at official stations and month since 1945. The other two hurricanes, Carrie and some unofficial amounts as high as 19 inches. There was Frieda, remained at sea in the Atlantic. Carrie persisted considerable damage to field and truck crops, particularly as a hurricane formore than two weeks and was responsible to tobacco and watermelons. Between 100 and 200 for the sinking of a ship near the with the loss of families were evacuatednear Perry, Fla. According to 80 lives. Frieda was of minorimportance and reached the Meteorologistin Charge at Jacksonville, at least hurricane force only a few hours before it began losing its nine tornadoes or damaging wind storms were reported tropical characteristics. in northeastern on the afternoon and evening of Including ,five tropical storms reached the 8th and another over Jekyll Island in south- the United States, all on the Gulf coast between eastern eastern Georgia. Nodeaths were reported from these Texasand northwestern Florida. None affected other tornadoes and the damage andinjuries were small. coastal areas of the Gulf of Mexico or the Caribbean and One small craft capsized in the Gulf of Mexico and five there were no along the entire eastern seaboard. of the seven persons aboard were apparently drowned. Propertydamage approximated $152,500,000 for the Damagein northwestern Florida from sea and rainfall UnitedStates; none occurred in otherareas. Audrey flooding from the mouth of the Suwannee Riverto PortSt. left 390 knowndead, including 263 identified and 127 Joe was estimated at $30,000 and damage from tidal action unidentified. There were 192 persons reported missing along the Florida west coast mas about $10,000. Tornado many of whom may be among the 127 unidentified dead. damage is estimated at $12,000. Therefore, total damage The loss of life in Audrey was the greatest of any tropical fromthis tropical storm was around $52,000 andthere storm in the United States since the hurri- were five deaths. cane of 1938 and emphasized the diaculty of insuring the HurricaneAudrey, June ,f25-%'8.--IIurricane Audrey, carrying out of adequate safety precautions and evacua- which struckthe Gulf coastnear the -Louisiana tion, even with the most recent methods of tracking and border on June 27 with devastating effect, first became early warnings. well defined over t,he Bay of Campeche,in the south- 2. INDIVIDUAL STORMS western Gulf of Mexico, on June 24. A weak easterly wave which moved into the area. a day or two earlier, as Tropical Storm (unnamed), June 8-i4.-Pressures were evidenced by changes in the wind field across the western abnormally low over thesouthwestern Gulf of Mexico Caribbean and Yucatan and byincreased shower activity, and Yucatan area on June 7 but lack of upper-air wind was probably instrumental in initiating the disturbance. observations from Mexico made the amount of circulation Klein [7] has discussed theformation and behavior in uncertain. However, late on the 7th and early on the 8th relation to the mean circulation for the period. He found it became evident that a tropical depression existed. It that it was possible, using the5-day 700-mb. height moved rather rapidly northeastwardwith some deepening anomalypatterns, to track a negativeanomaly center but little organization and crossed the Florida coastline associatedwith Audrey back to its appearancein the in Apalachee Bay during the early evening. Two ships, western Caribbean during theperiod June 11- 15. Namias one about 150 to 200 miles southeast of the center and [ll] has demonstrated the relation of hurricane genesis to later another 100 to 150 miles west of the center, reported areas of negativeanomaly on such mean charts. Two

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Unauthenticated | Downloaded 09/27/21 03:24 AM UTC DECEMBEB1957 MONTHLYREVIEW WEATHER 403 other factors recognized as important in hurricane forma- mb. and at Port Axthur, Tex., about an equal distance tion-warm sea-surface temperaturesand the proper west of the center, the lowest pressure was 966 mb. The divergent patternat high levels--.were present. While lowest pressure observed was 958 mb. by the Fish and Klein used the techniques of the Extended Forecast Sec- Wildlife Service at Hackberry, La. tion of theWeather Bureau, applying 5-day or longer The Hydrometeorological Section of the Weather BU- means to his analysis, the import.ance of some of the con- reau [9] has described the radialprofile of sea level pressure tributingfactors is also apparent when viewed froma of a model hurricane as: short-rangeaspect. For instance, the 200-mb. 5-day mean flow was shown to conform to the pattern suggested P”P0 -e-Rjr by Riehl [I31 as conducive to deepening. The 200-mb. Pn“P0 charts for the 25th to 27th show a marked intensification where p is the pressure at radius T, po the central pressure, of the ridge over the middle andeast Gulf, and, infer- p, the pressure to which the profile is asymptotic at some entially, of the high-level from the st.orm area distance from the center and R the radius at which the during this period. wind speedis greatest. Because of sparse data and the for tllr of The mean sea-surface temperatures Gulf lack of symmetry of the hurricane there is some leeway Mexico for J-unewere gencrally 2’ to 3’ above normal. F. in values which can be assigned to the parameters in this In addition, warming was evident preceding the develop- case, particularly p, and R. However, a minimum pres- ment of Audrey with the highest tempcraturcs (85’ F.) sure of 938 mb.as computed from the formula, seems in the area where the hurricane formed. consistent with reports of wind, , and damage.’ Audrey deepened duringthe night of June 24 while Calculationsusing empirical formulae pertaining to remainingnearly stationary. Aircraft reconnaissance on maximum wind and stormsurge and based on an estimated the morning of the 25th reported maximum winds of 85 central pressure of about 940 mb.agree well with the knots and minimum pressure 989 mb. Although moder- data collected for the hurricane. A peak wind speed of ateto severeturbulence was encountered, radar pres- 105 m. p. h. in a gust was read by from a wind dial entation was characterizedas “poor,” a feature which at Sulphur, La., before the anemometer blew away. An usuallyindicates that a tropicalstorm is not as active oil rig reported winds up to 180 m. p. h. and a pressure of or as“wet” as thosewith more definite rain bands. 925 mb. (It is not known whether this was a sustained Rapid deepening would therefore not normallybe ex- wind or a gust, or whether it was measured or estimated.) pected. Lateon the afternoon of the25th a second Four sea tendersof the ContinentalOil Company lost their flight reported that the maximum observed wind was 75 anchors and were adriftin the hurricane just ashort knotsand the minimumpressure 979 mb. On June 26 distance southeast of the center. The anemometers with boththe size andintensity of thehurricane increased which thesetenders were equipped(not calibrated fol- slightly.Reconnaissance showed maximum winds of90 lowing thehurricane), all indicated winds in excess of knotsand aminimum pressure of 973 mb.A radar 100 m. p. h.The three nearest the centerindicated tracking flight during the night of the 26th reported the winds of 140 to 150 m. p. h. (These were peakgusts precipitation field as considerablymore intensethan rather than sustained speeds and were read by eye from observed 24 hours previously. However, no central pres- the anemometer dial indicators. The anemometers were suremeasurement was obtained.The only additional 65 ft. abovewater.) Fletcher [3] has presented an em- observation of central pressure prior to the of the piricalformula for calculating maximum winds ina storm was that by the Tanker Tillamook nearlatitude topical storm. The formula, which is of the same form 28.7’ N., longitude 94.0’ W. from 0910 to 1025 GMT, June as those developed by Takahasi [15] and Myers [9], uses 27. The minimumpressure observed was969 mb. (The the difference between central andenvironmental pressure barometer was subsequentlycalibrated and the figure asa parameter. Fletcher’s formula, which according to of 969 mb. is the corrected value.) Indications are that Myers [lo] gives gust and not sustainedspeed, has proven the ship was in the western portion of the eye and that very reliable in operational use when the central pressure the pressure observed was not the absolute minimum in was known. If this formula is applied, using the central the center at that time. pressure now believed tohave existed in Audrey, the From June 26 until the centcr crossed the coast about indicated maximum wind is about 150 m. p. h. While this GMT on the 27th, Audrey increased its forward speed 1430 is in agreement with several unofficial reports of extreme from about 7 m. p. h. to 15 m. p. h. the same time At winds, theexact speed which occurred must remainin it intensified markedly. The centralpressure when it doubt. struck the coast was some 30 mb. lower than that last As is usual in hurricane catastrophies, the most damag- reported by reconnaissance andthere is no doubt that ing feature was not thewind but its indirect effects through there was considerable deepening in thefive hours between the storm surge. Nearly all the deaths can be attributed time of theobservation of the Tillawmok and landfall.

The exact minimum pressure as the center reached the 1 A manumipt by Eudson [5] hzs sincecome to our attention. In this, withthe coast hasnot been determined. The Calcasieu Coast methods outlined in [9], the most likely value of central pressure was calcul&d to be approximately 946 mb. with a 70 percent probabillty that the true value was between Guard station, 20 miles east of the center, reported 960 914 mb. aud 958 mb.

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* ESTIMATED It 0 I I I I I I I I I I I I I I I I I I I I I I I I -220 -200 -I80 :I60 -140 -120 -100 -80 -60 -40 -20 0 20 40 60 80 100 120 140 160 180 200 220240 260 2 DISTANCE IN MILES FIGURE3.--Maximum tide heights recorded during the passage of hurricane Audrey. to drowning by high tides. (See figs. 2 and 3.) Tides abnormally warm and increasing. It also seems possible were reported to be more than 12 feet above mean sea that sea surface temperatures near the coast may have level in Louisianafrom theCoast Guard Station at been even higher than those generally indicated by ship Calcasieu Pass to GrandCheniere, a distance of 24 miles.2 reports over the Gulf, since very shallow waters extend a Storm surgeforecasts are extremely difficult and beset considerable distance from shore in this particular area. with many complicating factors otherthan meteorological, In its later st~ages, the interaction of Audrey with the such as funnelling by coastal configuration or inbays, westerlies also created some forecast problems. As in slope of the continental shelf, and the astronomical tide some othernotable hurricanes of recentyears, strong stage. A formula has been developed by Conner, Kraft, baroclinic developmentsaccompanying this interaction and Harris 111 for computing the probable height of the coincided with,and probably contributed to, radical storm surge as a function of central pressure. Using 940 readjustment of the broad-scale pattern. Since this, a5 mb. as theminimum pressure, the formula indicates about well as the entire synoptic historyof Audrey, is covered in 12 feet as the probable height. There is a vital difference arecent a.rticle by Ross and Blum [14], it will not be between this value and theforecast of 7.5 feet which would discussed here. be obtainedusing the 973-mb. centralpressure last The exact number of deaths from Audrey will probably reported before the storm struck the coast. The capacity never be known. Thelist of known dead includes 371 of the hurricane to generatea deadly storm surge was in and near Cameron and 19 in other areas. To this list greatly increased bythe rapid deepening just prior to must be added a large number of others presumed dead landfall. from the 192 still listed as missing, although many of these While it is not now possible to explain the rapid deepen- may be among the 127 unidentifieddead. The loss of ing or to suggest how it might be anticipated in the future, life was the greatest in the United States since the New two possibly significant factorsmay be suggested. On England hurricane of 1938 and about equal to the total June 26, rises in the 200-mb. heights over the storm area for all other tropical storms in the United States in the accentuated the high-level pattern indicated by Riehl [I31 past decade. and Miller [8] as favorable to intensification. (A compu- Property damagein Audrey is estimated at $150,000,000. tation made on that date, using the procedure suggested In trhe Cameron to Grand Cheniere area, 60 to 80 percent by Miller, indicated 936 mb. as the potential depth of the of the houses were destroyed or floated off their founda- hurricane.)Sea surface temperatures, recognized as an tions. Inundation extendedinland as much as 25miles important factor in development of tropical storms, were overthe low-lying area (seefig. 2). As the hurricane moved northeastwardfrom Louisiana., it gradually weakened and began losing its tropicalcharacteristics a A high water mark found on Oak Grove Ridge, just north of the mouth of the Mer- mentau River, was subsequently established as 13.9 ft. m. s. 1. by Corps of Engineers. but was still attended by some damaging winds on the

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28th. Severaltornadoes formed southeast of the storm 11' N., longitude 25' W. On September 6 the SS Ajrican cent,er and injured 14 persons in . Re-intensifi- Star, about 700 miles west of the Cape Verh Islands, for- cation occurred due to extratropical processes as the storm warded a succession of special reports showing falling move,d from the Valley through the eastern Great pressure, increasing winds, and sqnalliness. The existence Lakes region and therewas a large amountof flood damage of was confirmed wlrclll the 1600 GMT re- in States southof the , particularly inIllinois port (somewhat delayed) showed an east-northeast wind andIndiana, and some damagefrom high winds and of 92 m. p. h. and a pressure of 1,001 mh. Later analyses thundersqualls from western Pennsylvania through New indicate that the vortex noted on the 2d was the genesis York. Winds were reportedas high as 65 m. p. h.at stage of Carrie and that it moved west-northwestward at , Pa., and95 to 100 m. p. h. at Jamestown, X. Y. about 12 m. p. h. to the position at which it wa.s encount- TropicalStorm Bertha, August 8-il .-A weak extra- ered by the African Star. tropical Low entered the northeastern Gulf of Mexico on On September 7, in an unusually long flight, the regular August 6 and drifted slowly westward for the next 2 days. ,4ir Force Gull reconnaissance plane from was It developed into a tropical storm about 100 miles south diverted t~otmhe st'ormarea. The observer reported max- of the mouth of the River on August 8, then imum winds of 138 m. p. h. at, the 700-mb. level with a moved in a general northwesterly direction, crossing the well-defined eye 20 miles in diameter and a minimum coast near Cameron, La.., late on August 9. Since it was surface pressure of 945 mb. Using hhis cent.ral pressure, moving toward the same portion of the coa,st devastated as obtained by dropsonde, and the formula developed by by hurricane Audrey 2 months earlier, Bertha was viewed Fletcher [3], maximum surface winds were calculated to be with alarm by the popula.tion and full safety precautions about 130 m. p. h. Reconnaissance on the next. 4 days andevacuations were evidently carried outpromptly. showed a gradual rise in cent'ral pressure and on t>he11th Fortunately, Bertha did not develop to full hurricane in- t.he,minimum pressure was 984 mb. and t,he highest winds tensity. Highest winds were e,st.imate,dby ships and land were reported as about 70 m. p. h. The wcalrcning of the stations at 50 t,o 70 m. p. h. The fastest mile at Beau- hurricane was apparenblydue t,o decreasing pressure mont, Tex., was measured at 44 m. p. 11. wit,h gusts to 52. gradient t,o the nort,h as a low pressure trough formed Tidesdid notapproach the disastrousproportions of across thesubtropical High t,o a deepening Lownear those in Audrey, the highest re,ported being 4.7 feet at the Xewfoundland. This Low moved sout,hward, reaching west end of Vermilion Bay.The heaviestrainfall ob- its most southcrly position on t.hc 11t'h, after which it served was 10.73 inches at Livingston, Tex. begm a slow retreat to t,he nort,h. Carrie, having curved The storm weakened and turned northward after mov- tro a northerly course at this time, cont,inued northward at ing inland,reaching southeastern Oklahoma on August 7 to 10 m. p. h. until September 14 when rebuilding of the 11. Although the storm was not identifiable as a surface high pressure ridge over the north Atlantic forced it to circulation thereafter, it was apparent in the circulation change course toward thenorthwest. This change in aloft and in the accompanying heavy rains as it turned direction was accompanied by reintensification, and on the eastward across .Two deaths resultingfrom 12th reconnaissance aircraft found maximumwinds of 108 Bertha were reported; property damage was slight, and m. p.h. and minimumsea level pressure of 960mb. the accompanying rain has been described by the Mete- There were heavy wall clouds in all qwdrants except the orologist in Charge at Weather Bureau Office southwest:. A continued increase in intensity and in size as over-all more beneficial than harmful. culminated on the 16t,hin what National Hurricane The failure of Bertha to intensify similarly to Audrey ResearchProject observers characterizedas one of the may have been related to the broad-scale flow pattern. most perfectlyformed hurricanes theyhad seen. The Green [4] has noted that in June,a strong trough prevailed winds of 138 m. p. h. reported on this date were the max- in the 700-mb. mean pattern over t,hecentral United imumsurface winds observed duringthe life of Carrie States, while in August this had been replaced by a strong but it is likely that higher wind speeds occurred during the High. The 200-mb. charts also indicate thatthe high- period of lowest central pressure on September 7 and 8. level outflow pattern was less favorablefor deepening than When the hurricanepassed to the northeastof Bermuda in the case of Audrey. on the 16th, poor radar definition and an increase in the Hurricane Carrie, September %"%$.-In early September diameter of the eye to 40 to 70 miles indicated weakening. the circulation pattern over the eastern Atlanticresembled However, as it curved eastward in advance of a trough that found by Namias and Dunn [12] to be characteristic moving into the North Atlantic, it still maintained max- of periods in which tropical storms develop in the Cape imum winds of near 100 m. p.h. for the next several days. Verde area. The northeastward extension of the Azores On the 21st the German sailing ship encountered High produced above-normalpressures in thearea of the stormsout,hwest of the Azores and went down with the western Europe while a trough prevailed near the west loss of 80 of her 86 crew members.Insufficient reports coast of Africa. Observations from the Cape Verdes on were obt,ained to indicate the maximum wind and lowest September 2 showed evidence of a vortex passing just to prwsures observed as it passed through the Azores the the sout,h of t'he islands, and a message from Panair do n(>stday but it is likely that winds of hurricane force Brasil reported a t,ropical storm developing near latitude prrsist,ed.Carrie began to assumeextrat,ropical featureE

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thereafter and accelerated to the northeast, lashing the tothe east of thecenter. The highestreported wind British Isles with high winds on the 24th and 25th and speed was 52 m. p. h. at Pensacola airport, with gusts to causing tremendous waves on the coast and floods ove,r 75 m.p. h. The lowest pressure observed on land was parts of the Isles. 1003 mb. at New Orleans and McComb, La., with 1000 Carrie was chart'edover one of the longest tracks, mb. reported by reconnaissance aircraft before the storm probablythe longest tra,ck, of record-approximately reached land. 6,000 miles from its origin off the African coast to near Squalls and heavy rains occurred in advance and to the Bermuda and backacross the Atlantic to the BritishIsles. east of the central area andcontinued along the Mississippi Formal advisories were issued from September 6 to 21 and and Alabama coasts and nearthe mouthof the Mississippi additional advices were issued through the NSS bulletin River well after it passed. Five inches of rain fell at (report from Navy Radio station at Annapolis) after it Buras,La., in 2% hourswith a total of over 13 inches passed east of longitude 35' W. on thatdate. Aircraft there. Amounts ranging upwards from 6 inches through reconnaissance of Carrie was of unusual quality. The Air southeasternLouisiana and near the Mississippi and Force flights fromBermuda on the 7th and 21st went Alabama coasts resulted in some flooding in those areas. farther east than any previous hurricane reconnaissance The property damage chargeable to Esther was estimated flight and the initial flight on the 7th covered approxi- at $1,500,000 andthree deaths were attributableto mately 3,700 miles with almost 17 hours in the air. the storm. Tropical Storm Debbie, September 7-8.-0n September 5 Hurricane Frieda, September 20--27.-Hurricane Frieda there was evidence of a weak easterly wave moving from spent its life at sea and was of hurricane force for only a the Caribbean into the Gulf of Mexico where a stagnant few hours.The circulation which developed intothis uppertrough prevailed. This wave was apparentlythe storm beganon September 20. A cold front pushing trigger which set off a weak circulation in the central Gulf southward to the rearof Hurricane Carriepassed Bermuda onSeptember 7. This depression moved northeastward and a low center of 1010 mb., appearing at first to be and only barely reached storm force before going inland nothingmore thanan incipientfrontal wave, rapidly near Fort Walton, Fla., about 40 miles east of Pensacola, developed. Elsewhere, significant features were a 1020- on the morning of the 8th. Highest winds reported were mb. surface anticyclone some 700 miles to the north, and around 40 m.p. h. at St. Marks. Tampa had gust's to northerly winds of near 55 m. p. h. at 500 mb. and higher 52 m. p. h.in a squall. The highest tidereported was over the surface cyclone. By early morning of the 21st, some 150 miles east of the center on Apalachee Bay where strong easterly winds of 63 m. p. h. were observed at the it ranged from 2% to 4 feet. Some flooding occurred due gradient level at Bermuda.The LST Nurvik reported to the tidesand rains, which were locally heavy,with the central pressure in the developing storm, about 400 9.10 inches at Crawfordsville, Fla. There were no fatal- miles south-southwest of Bermuda, as 1005 mb. Several ities as a direct result of the storm although it was in- factorsfavored intensification at thistime. Thestrong directly responsible for four deaths. low-level easterly winds north of the area resulted in a The failure of Debbieto intensify furthermay be strong cyclonic shear, the sea surface temperatures were attributable to two factors. The upper-air pattern never verywarm, raobs from the Narwik and from Bermuda conformed to that found tofavor intensification [8,13]. In indicated that the cold fronthad dissipated, and there addition, there was evidence that cooler air entered the were favorable high-level windsfor evacuation. By circulation as it moved near the coast. evening of the 21st, aircraft reconnaissance showed that Tropical Storm Esth.er, September 16-1 9 .-Squalliness central pressure had fallen to 1001 mb. and winds were and abnormally low pressure in the southwestern Gulf of up to 60 m. p. h. in squallseast of the center.Frieda Mexico on September 15 indicated that a tropical depres- was a reality. The movement was rather slow tothe sion mightbe forming. Forabout 2 days prior tothis southwest. date a weak cyclonic circulation aloft had been drifting Reconnaissance on the morning of September 22 found northwestward across Central America toward the Gulf. maximum winds of 50 to 60 m. p. h. in gusts withsustained On the evening of the15th the New Orleans Weather winds generally 30 to 40 m. p. h. Shower activity was Bureau Office issued a bulletin announcing the develop- considerably less than norms1 and there was no extensive ment of a depression and forecastingintensification. cloud shield. Meanwhile, upper winds at Bermuda were Esther grew to storm intensity by late on the 16th and rapidly vee,ring fromnortherly to southeasterly with began moving northward at about 10 m. p. h. It never decreasing speeds. This occurred as a high-level anti- developed into a typical tropical storm with a small, well- cyclone northwest of thestorm weakened and splitin defined eye but remained with a large area of relatively response to theapproach of a short wave in the westerlies. light winds roughly 100 miles across. Thisarea passed This left the upper ridge with two cells, one over Florida inland on thesoutheastern Louisiana coast about day- and the other northeast of Bermuda. break on September 18, subsequentlymoving upthc With a less favorable Circulation for intensification, Mississippi Valley and weakeqing. As in the case of the Frieda showed little change through the 23d. At the same fist storm of the season (unnamed) and Debbie, much of time,recurvature was favored bythe new circulation the squalliness and high wind was a considerable distance pattern around the storm and it began to move toward

Unauthenticated | Downloaded 09/27/21 03:24 AM UTC 408 MONTHLY ”TATHER REVIEW DECEMBE~1957 the northwest and north at about 10 m. p. h. during the west in the area of Bermuda, the pressure gradient there night of the 23d. Simultaneously,as the short wave in having been weakened by theapproach of an extratropical the westerlies progressed eastward,the upper trough system which graduallyabsorbed the remnants by the weakened and, perhaps in response to a more favorable 27th. This storm never developed many of the character- high-level evacuation mechanism, the cloud systems began istics of a true and in many respects was to show more organization and radar coverage became similar to tropical storms Dora and Ethel of 1956 and a feasible for the first time. Forward velocity increased to quasi-tropical Low of October 1956 [2]. It caused no 20 m. p. h. toward the north-northeast on the 24th and deaths or property damage. little change was observed in surface pressures. However, ACKNOWLEDGMENT by morning of the25th, the Canadian merchant ship Irvingbrook reported a barometer reading of 992 mb. and Portions of this article arebased upon individual storm 80-m. p. h. winds. Frieda now was a hurricane-but accounts by Mcssrs. Gordon E. Dunn, Walter R. Davis, only for a few hours for the cold front associated with and Arnold L. Sugg of the Miami Weather Bureau Office, the short wave mentioned previously was dropping into andby Mr. StephenLichtblau of the New Orleans her circulation. Some further decrease in central pressure Weather Bureau Office. occurred as shown by a reportfrom the ship African REFERENCES Lightning, giving apressure of 978 mb. However,this 1. Vi. C. Conner, R.H. Kraft, and D. Lee Harris, “Empirical was interpreted as the result of extratropical deepening Methods for Forecasting the Maximum Storm Tide Due to since thestorm was spreading outand there was no Hurricanesand Other Tropical Storms,” Monthly Weather observed wind speed such as the 115 m. p. h. that Fletch- Review, vol. 85, No. 4, Apr. 1957, pp. 113-116. er’s[3] formula would indicate under true tropical con- 2. G. E. Dunn, ITr. R. Davis, and P. L. Moore, “Hurricane Season of 1956,” MonthlyWeather Review, vol. 84, No. 12, Dec. ditions with such a pressure. 1956, pp. 436-443. Although Frieda beganunder conditions not clearly 3. It. D. Fletcher, [‘Computation of Maximum Surface Winds in tsropical and became extratropical shortly after reaching Hurricanes,” Bulletin of the American Meteorological Society, hurricane force, soundings taken in the storm averaged vol. 36, No. 6, June 1955, pp. 246-250. slightlywarmer thanthe meantropical atmosphere. 4. Raymond A. Grcen, “The Weather and Circulation of August 1957,” MonthlyWeather Review, vol. 85, No. 8, Aug. 1957, Aircraft dataand surfacepressures also showed good pp. 282-257. agreement with the relation given by Jordan [6] for tropi- 5. Gcorgina Hudson, Pressure,Wind Speeds, and Directions in cal cyclones. However, throughout the life of the storm, Hurricane Audrey, June 27, 1957, Hydrometeorological Sec- the favorable parametersfor hurricane formation and tion, UnitedStates Weather Bureau, Washington, D. C. maintenance seem never tohave operated concurrently 1957 (unpublished). 6. C. L. Jordan, “Estimating CentralPressure of Tropical Cyclones or for long enough periods to produce a typical hurricane. from Aircraft Data,” NationalHurricane Research Project After becoming extratropical,Frieda continued rapidly Report No. 10, Bug. 1957, 12 pp. (pp. 8-11). northeastward,with gradually decreasing intensity, and 7. Wm. H. Klcin, “The Weather and Circulation of June 1957- passed across Newfoundland on the night of the 26th. Includingan Analysis of Hurricane Audrey in Relation to No deaths or property losses have been charged to this the Mean Circulation,” MonthlyWeather Review, vol. 85, No. 6, June 1957, pp. 208-220. storm. 8. B. I. Miller, “On theMaximum Intensity of Hurricanes,” Tropical Storm (unnamed), October 22-27.-0n October NationalHurricane Research Project Report No. 14, 1957, 22 and 23, shower activity increased and pressures began 19 PP. falling near and to the north of the Lesser Antilles. A 9. V. A. Myers, “Characteristics of UnitedStates Hurricanes strong upper trough extended from the vicinity of Ber- Pertinentto Levee Design for Lake Okeechobee, Florida,” HydrometeorologicalReport No. 32, UnitedStates Weather muda to Puerto Rico and on October 23 a small cut-off Bureau, Washington, D. C. 1954. Low developed inthis trough. The surfacecirculation 10. V. A. Myers,“Maximum Hurricane Winds,” Bulletin of the increased markedly on this date, and in theevening a ship AmericanMefeorological Society, vol. 38, No. 4, Apr. 1957, near the center of the circulation at about latitude25’ N., pp. 227-228. longitude 63’ W., reported a barometer of 999 mb. and 11. J. Namias, “Long RangeFactors Affecting the Genesis and Paths of Tropical Cyclones,” Proceedings of the UNESCO winds up to 35 m. p. h. On the 24th reports showed that Symposium on Typhoons, 9-19 November 1964, Tokyo, 1955, therehad been further intensificationwith winds in pp. 213-219. squalls up to 50 to 60 m. p. h. just northof the center and 12. J. Namias and C. R. Dunn, “The Weather and Circulation of winds of 30 to 35 m. p. h. prevailing 200 to 400 miles from August 1955-Including the Climatological Background for the center. Thestorm gradually curved from a north- Hurricanes Connie andDiane,” MonthlyWeather Review, v01. 81, NO. 8, Aug. 1955, pp. 163-170. westerly to a northerly direction at 12 to 15 m. p. h. The 13. H. Riehl, “A Model of HurricaneFormation,” Journal of lowest surface pressure reported was 993 mb. by a ship Applied Physics, vol. 21, No. 9, Sept. 1950, pp. 917-925. near 28’ N., 65’ W. at 0600 GMT on the 25th. A gradual 14. RobertD. Ross and Maurice D. Blum, “Hurricane Audrey, weakening and filling began thereafter with acceleration 1957,” MonthlyWeather Review, vol. 85, No. 6, June 1957, tothe northeast. When the storm passed justeast of pp. 221-227. 15. K. Takahasi, “Distributionof Pressure andWind in a Typhoon,’, Bermuda on the evening of October 25, there were strong Journal of theMeteorological Society of Japan, 2d Series, winds east of the center but only moderate winds to the VO~.XVII, NO. 11, NOV.1939, pp. 417-421.

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