DTIC ADA400213: 1976 Annual Typhoon Report

98 Pages·7.2 MB·English

by  Defense Technical Information Center

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1.REPORTDATE(DD-MM-YYYY) 2.REPORTTYPE 3.DATESCOVERED(FROM-TO)
01-01-1995 AnnualTyphoonReport xx-xx-1995toxx-xx-1995
4.TITLEANDSUBTITLE 5a.CONTRACTNUMBER
1976AnnualTyphoonReport 5b.GRANTNUMBER
Unclassified
5c.PROGRAMELEMENTNUMBER
6.AUTHOR(S) 5d.PROJECTNUMBER
Morford,DeanR.; 5e.TASKNUMBER
Pilipowskyj,Serhij;
5f.WORKUNITNUMBER
7.PERFORMINGORGANIZATIONNAMEANDADDRESS 8.PERFORMINGORGANIZATIONREPORT
JointTyphoonWarningCenter NUMBER
425LuapeleRoad
PearlHarbor,HI96860-3103
9.SPONSORING/MONITORINGAGENCYNAMEANDADDRESS 10.SPONSOR/MONITOR'SACRONYM(S)
NavalPacificMeteorologyandOceanographyCenter 11.SPONSOR/MONITOR'SREPORT
JoingTyphoonWarningCenter NUMBER(S)
425LuapeleRoad
PearlHarbor,HI96860-3103
12.DISTRIBUTION/AVAILABILITYSTATEMENT
APUBLICRELEASE
,
13.SUPPLEMENTARYNOTES
SeeAlsoADM001257,2000AnnualTropicalCycloneReportJoingTyphoonWarningCenter(CDincludes1959-1999ATCRs).Block1and
Block3shouldbe1976.
14.ABSTRACT
TheAnnualTyphoonReportsummarizesthetropicalcyclonesoccurringduring1976inthewesternNorthPacific,theCentralNorthPacific
andtheNorthIndianOceans.TheUnitedStatesNationalWeatherServicepublishessummariesofeasternNorthPacifictropicalcyclonesin
theMarinersWeatherLog,andPilotCharts.
15.SUBJECTTERMS
16.SECURITYCLASSIFICATIONOF: 17.LIMITATION 18. 19.NAMEOFRESPONSIBLEPERSON
OFABSTRACT NUMBER Fenster,Lynn
PublicRelease [email protected]
97
a.REPORT b.ABSTRACT c.THISPAGE 19b.TELEPHONENUMBER
Unclassified Unclassified Unclassified InternationalAreaCode
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703767-9007
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Indian Ocean Area (Malay Peninsula to Africa) Pacific Area (Dateline to Malay Peninsula)
AREA OF RESPONSIBILITY -
JOINT TYPHOON WARNING CENTER, GUAM
1,..,,.:
U. S. FLEET WEATHER CENTRAL
JOINT TYPHOON WARNING CENTER
COMNAVMARIANAS BOX 17
FPO SAN FRANCISCO 96630
DEAN R. MORFORD
Captain, United States Navy
COMMANDING
SERHIJ PILIPOWSKYJ
Lieutenant Colonel, United States Air Force
DIRECTOR, JOINT TYPHOON WARNING CENTER
STAFF
*LCDR Ed~ar- J. Ha~-i~on, Jr. , USN
LCDR David Sokol, USN
*LT Douglas R. Moran, USN
LT Gary R. Willms, USN
LT George T. McKaige, USN
*CAPT Charles R. Sikora, USAF
CAPT Frederick P. Milwer, USAF
CAPT Charles P. Guard, USAF
ENS Edward M. Fukada, USNR
MSGT Philip A. Charron, USAF
SSGT Ellis D. Spencer, USAF
*SSGT Maurice L. Wymore, USAF
SSGT Bobby L. Setliff, USAF
AG2 Greg P. Metzger, USN
AG3 Robert L. Hem, Jr., USN
AG3 Susan J. Funk, USN
*AGAN Deborah H. Walker, USN
AGAN Deirdre A. Wexler, USN
SRA Craig A. Anderson, USAF
AIC Vandora A. Barnes, USAF
Ms. Gail E. James, Secretary
CONTRIBUTOR
Det 1, lWW - USAF
1976
ANNUAL TYPHOON REPORT
*Departed during 1976 season
FRONT COVER:
ln@aaed photograph o{ Supw Typhoon
Pame&a neaz peak .Lntzntitg275 nm ~ou.thea~i
o~ Guam, 19 Mag 1976, 090JZ. Pame.ta
bub4equwtLg pab~ed difiecZlg owes Guam
in&LiczXng mUA&-V’Zdatmgc -to niilitamyand
UVifiUn ~atififl~b. P(?.ta.itb 0~ thih
deb.tauctiue b.tohmbe~n on page 24.
(OMSPimagahg]
ii
For centuries tropical cyclones have been Equator, west of the Date Line, and east of the
a menace to both military and civilian activi- African coast [JTWC area of responsibility)
ties in tropical and subtropical oceanic for potential tropical cyclone development;
regions. During recent times much effort has
been funneled toward more accurate tropical 2. Provide warnings for all tropical
cyclone forecasts, and toward more efficient cyclones within the area of responsibility;
operational responses to these storms. A
large portion of this effort has been based 3. Determine tropical cyclone recon-
on studies which, if meaningful, must be based naissance requirements and assign priorities;
on accurately documented data. The Annual
Typhoon Report represents such documentation. 4. Conduct post-analysis studies
The body of this report summarizes the trop- including preparation of the Annual Typhoon
ical cy;lones occurring during 1976 in the Report; and
western North Pacific, the Central North
Pacific and the North Indian Oceans. The 5. Conduct tropical cyclone research
United States National Weather Service pub- and forecast improvement studies as time
lishes summaries of eastern North Pacific permits.
tropical cyclones in the Mariners Weather
~, and Pilot Charts. JTWC is an integral part of FLBWEACEN Guam
and is manned by officers and enlisted personnel
The PACOM Tropical Cyclone Warning from both the Air Force and Navy. The senior
System (westernNorth Pacific and Indian Air Force officer is designated as the Direc-
Oceans) insures warnings of these dangerous tor, JTWC, and the senior Naval officer as
storms is provided to all U. S. government the Deputy Director, JTWC.
interests. It consists of the Fleet Weather
Central/Joint Typhoon Warning Center Detachment 17, 30th Weather Squadron,
(FLEWEACEN/JTWC), the U. S. Air Force 54th Yokota AS, Japan with assistance from the
Weather Reconnaissance Squadron stationed at Naval Weather Facility, Yokosuka, Japan and
Andersen AFB, Guam, and the U. S. Air Force computer support from Fleet Weather Central,
Weather Service Defense Meteorological Satel- Pearl Harbor, Hawaii is designated as the
lite Program (DMSP) sites at Nimitz Hill,.Guam; Alternate Joint Typhoon Warning Center in the
Clark AB, Philippines; Kadena AB, Okinawa; event that FLEWEACEN/JTWC, Guam is incapaci-
Osan AB, Korea; Hickam AFB, Hawaii; and the tated.
Air Force Global Weather Central, Offutt AFB,
Nebraska. Additionally, satellite support is The Central Pacific Hurricane Center,
provided by.the Fleet Weather Facility, Honolulu, Hawaii, is responsible for the
Suitland, Maryland. area north of the equator from the Date Line
east to 140W. Warnings are issued in coordi-
The Fleet Weather Central/Jotit Typhoon nation with FLEWEACEN, Pearl Harbor and
Warning Center, Guam has the responsibility Detachment 4, lWW, Hickam AFB, Hawaii.
to:
CINCPACFLT, CDRUSACSG, and CINCPACAF are
1. ,Providecontinuous meteorological responsible for further dissemination, and if
watch of all tropical activity north of the necessary, local modification of tropical
cyclone warnings to U. S. government interests.
iii
TABLE OFCONTENTS
CHAPTER I OPERATIONAL PROCEDURES page
1. General---------------------------------------------------- 1
2. Analyses and Data Sources---------------------------------- 1
3. Forecast Aids---------------------------------------------- 1
4. Forecasting Procedures------------------------------------- 2
5. Warnings--------------------------------------------------- 2
6. Prognostic Reasoning Message------------------------------- 2
7. Significant Tropical Weather Advisory----------------------
8. Tropical Cyclone Formation Alert---------------------------
CHAPTER II RECONNAISSANCE AND COMMUNICATIONS
1. Wneral ---------------------------------------------------- 3
2. Reconnaissance Responsibility and Scheduling--------------- 3
3. Aircraft Reconnaissance Evaluation Criteria---------------- 3
4. Aircraft Reconnaissance Summary---------------------------- 4
5. Satellite Reconnaissance Summary--------------------------- 5
6. Radar Reconnaissance Summary------------------------------- 6
7. ComunicatiOns --------------------------------------------- 6
CHAPTER III RESEARCH SUMMARY
1. General---------------------------------------------------- 7
2. Cross-Equatorial Interactions in the Development of a
Winter Typhoon: NANCY 1970-------------------------------- 7
3. Tropical Cyclone Center Fix Data for the 1975
Typhoon Season--------------------------------------------- 7
4. An Evaluation of Utilizing Equivalent Potential
Temperature as a Measure of Tropical Cyclone Intensity----- 7
5. Radius of Wind Field Surrounding a Tropical Cyclone-------- 7
6. Correlation of JTWC Initial Position Error to Forecast
Position Errors in the Western North Pacific--------------- 7
7. The Influences of the Tropical Upper Tropospheric
Trough (TUTT)on Erratic Movement of Tropical Cyclones----- 7
8. The Development and Movement of Tropical Cyclones
in Deep Southwesterly Monsoon Surges----------------------- 8
9. Operational Applications of a Recurvature -
Non-Recurvature Study Based on 200 MB Wind Fields---------- 8
CHAPTER IV SUMMARY OF TROPICAL CYCLONES
1. General Resme --------------------------------------------- 9
2. Western North Pacific Tropical Cyclones-------------------- 13
3. Individual Typhoons---------------------------------------- 18
page page
Typhoon Kathy------ 18 Typhoon Anita---- 36
Typhoon Marie------ 20 Typhoon Billie--- 38
Typhoon Olga------- 22 Typhoon Fran----- 42
Typhoon Pamela----- 24 Typhoon Hope----- 46
Typhoon Ruby------- 30 Typhoon Iris----- 48
Typhoon Sally------ 32 Typhoon Joan----- 50
Typhoon Theresa---- 34 Typhoon Louise--- 52
4. North Indian Ocean Tropical Cyclones----------------------- 56
5. Central Pacific Tropical Cyclones-------------------------- 58
6. Tropical Cyclone Center Fix Data--------------------------- 60
CHAPTER V SUMMARY OF FORECAST VERIFICATION DATA
1. Annual Forecast Verification------------------------------- 61
2. Comparison of Objective Techniques------------------------- 61
3. Pacific Area Tropical Storm and Depression Data------------ 67
4. Pacific Area Typhoon Data---------------------------------- 72
5. Indian Ocean Area Cyclone Data----------------------------- 83
6. Central Pacific Hurricane Data----------------------------- 85
APPENDIX ABBREVIATIONS, ACRONYMS AND DEFINITIONS
1. Abbreviations and Acronyms--------------------------------- 86
2. Definitions------------------------------------------------ 86
DISTRIBUTION 88
v
CHAPTER I - OPERATIONAPLROCEDURES
1. GENERAL
Services provided by the Joint Typhoon (4)Additional sectional’analyses
Warning Center (JTWC) include the following: similar to those above. at intermediate
(1) Significant Tropical Weather Advisories synoptic times, during”periods of tropical
issued daily describing all tropical distur- cyclone activity.
bances and their potential for further
development; (2) Tropical Cyclone Formation c. AIRCRAFT RECONNAISSANCE:
Alerts issued whenever interpretation of
satellite and synoptic data indicates likely These data are invaluable in the
formation of a tropical cyclone; (3)Tropical positioning of centers of developing systems
Cyclone Warnings issued four times daily and essential for the accurate determination
whenever a significant tropical cyclone of the maximum intensity, minimum sea-level
exists in the Pacific area; (4)Tropical pressure, and radius of significant winds
Cyclone Warnings issued twice daily whenever exhibited by tropical cyclones. Aircraft
a significant tropical cyclone exists in the reconnaissance data are plotted on large-
Indian Ocean area; and (5) Prognostic scale sectional charts for each mission flown.
Reasoning issued twice daily for tropical A comprehensive discussion of aircraft recon-
storms and typhoons in the Pacific area. naissance is presented in Chapter II.
FLEWEACEN Guam provides computerized d. SATELLITE DATA:
meteorological/oceanographic products for
JTWC. Communication support is furnished The Defense Meteorological Satellite
by the Nimitz Hill Naval Telecommunications Program (DMSP)played a major role in the
Center (NTCC) of the Naval Communications early detection of tropical cyclones in
Area Master Station Western PaClflC. 1976. A discussion of this role, as well as
applications of satellite data to tropical
cyclone tracking, is presented in Chapter II.
2. ANALYSES AND DATA SOURCES
e. RADAR:
a. COMPUTER PRODUCTS:
During 1976, land radar coverage was
Varian plotted charts are routinely
utilized more extensively in the Selective
produced at synoptic times for the surface,
Reconnaissance Program than ever before.
850 mb, 700 mb, and 500 mb. A chart of upper
Once a storm moved within the range of a
tropospheric data is produced which utilizes
land radar site, reports were usually
200 mb rawinsonde data and AIREPS above
received hourly. Use of radar during 1976
29,000 ft within 6 hours of the 00002 and
is discussed in Chapter II.
12002 synoptic times.
JTWC utilizes the FLEWEACEN Guam 3. FORECAST AiDS
Computer Center for objective forecast
techniques and statistical post-analysis. a. CLImTOLOGY:
In addition, the standard array of Climatological publications utilized
synoptic-scale computer analyses and prog- during the 1976 typhoon season include Dre-
nostic charts are available from the Fleet vious JTWC Annual–Typhoon Reports and ciimatic
Numerical Weather Central (FNWC) at publications from Fleet Weather Central Guam,
Monterey, California. Director Naval.Oceanography and Meteorology,
Naval Weather Research Facilityr Naval Envi-
b. JTWC ANALYSES: ronmental Prediction Research Facility, Naval
Postgraduate School, Air Weather Service, First
(1) Combined surface/gradient level Weather Wing and Chanute Air Training Center,
(3,000 ft) streamline analysis over tropical plus publications from other Air Force and
regions and anisobaric analysis in more Navy activities, various universities and
northern latitudes and around intense trop- foreign countries.
ical systems at 00002 and 12002. The blend
between streamlines and isobars fluctuates b. OBJECTIVE TECHNIQUES:
as the pressure gradient changes from season
to season. Low-level wind directions from The following objective techniques
satellite data are included in the analysis. were employed in tropical cyclone forecasting
during 1976. A description and an evaluation
(2) 500 mb contour analysis at of these techniques is presented in Chapter
00002 and 12002. v:
(3) Composite upper-tropospheric (1)TYFN75
streamline analysis, utilizing rawinsonde data (2)MOHATT 700/500
from 300 mb through 100 mb, wind directions (3)FCSTINT
extracted from satellite data by Det 1, lww (4) 12-HR EXTRAPOLATION
and AIREPS (plus or minus 6 hours) at or above (5) HPAC
29,000 feet, at 00002 and 12002. (6)XT24
(7) INJAH74
1
4. FORECASTING PROCEDURES
a. INITIAL POSITIONING: seven hours apart. This variable warning
time allows for maximum use of all available
An initial center position is reconnaissance platforms and spreads the
determined from a subjective evaluation of workload in multiple storm situations. The
center fix data and synoptic data. When forecast intervals for all tropical cyclones,
these data sources are not available, extrapo- regardless of intensity, are 12-, 24-, 48-,
lation from the previous position is used. and 72-hr.
b. TRACK FORECASTING: Warnings in the JTWC Indian Ocean
area are issued within 2 hours of 08002
An initial forecast track is and 2000Z with the constraint that 2
developed based on persistence, climatology consecutive warnings may not be more than
and obiective techniques. This initial track fourteen hours apart. Warnings for this area
is sub~ectively modi~ied based on the are issued only after a tropical cyclone haS
following: attained an intensity of greater than 33 kt.
Forecast intervals are 24 and 48 hours.
(1) The prospects for recurvature are
evaluated for all westward and northward Warning forecast positions are verified
moving storms. This evaluation is based against the corresponding post analysis
primarily on present and forecast position “best track” positions. A summary of the
and amplitude of middle tropospheric mid- verification results for 1976 is presented
latitude troughs from the latest 500 mb in Chapter V.
analysis and numerical prognoses.
(2) Determination of steering level 6. PROGNOSTIC REASONING MESSAGE
is partly influenced by maturity and vertical
extent of the system. For mature storms. In the Pacific Area, prognostic reasoning
located south of the 500 mb subtropical ridge, messages are transmitted at 00002, 12002 or
forecast changes in speed of movement are whenever the previous reasoning is no longer
closely correlated with forecast changes in valid. This message is intended to provide
the intensity of the ridge. When steering field meteorologists with the reasoning behind
currents are very weak, the tendency for the latest JTWC forecast. Prognostic reasOn-
storms to move northward due to internal ing messages are not prepared for tropical
forces is an important consideration. depressions nor for the Indian Ocean area.
(3) Over the 12- to 72-hr forecast
7. SIGNIFICANT TROPICAL WEATHER ADVISORY
spectrum, speed of movement during the early
time frame is biased toward persistence,
This message, summarizing significant
while that near the end of the time frame is
weather in the entire JTWC area of responsi-
biased towards analogs and climatology.
bility, is issued by 06002 daily. It contains
a detailed, non-technical description of all
(4)A final check is made against
significant tropical disturbances, and the
climatology to ascertain the likelihood of
JTWC evaluation of potential for tropical
the forecast track. If the forecast devi-
cyclone development.
ates greatly from climatology, the forecast
rationale is reappraised and the track
adjusted as necessary. 8. TROPICAL CYCLONE FORMATION ALERT
c. INTENSITY FORECASTING: Alerts are issued whenever interpretation
of satellite and other meteorological data
In forecasting intensity, heavy indicates significant tropical cyclone forma-
reliance is placed on aircraft reconnaissance tion is likely. These alerts will specify a
reports, the Dvorak satellite interpretation valid period not to exceed 24 hours and must
model, and the objective techniques discussed either be cancelled, reissued or superseded
above. Additional considerations are the by a warning prior to expiration of the valid
position and intensity of the tropical upper- period.
tropospheric trough, extent and intensity
of upper-level outflow, sea surface tempera-
ture, terrain influences, speed of movement,
and proximity to an extratropical environment.
5. WARNINGS
Tropical cyclone warnings are numbered
sequentially. If warnings are discontinued
and the storm reintensifies, warnings are
numbered consecutively from the last warning
issued. Amended or corrected warnings are
given the same numberas the warnings they
modify plus a sequential alphabetical desig-
nator. Each warning includes the location,
intensity, direction and speed of movement,
and the radial extent of 30, 50,and 100 kt
surface winds (when applicable). Warnings
within the JTWC Pacific Area are issued with-
in 2 hours of 00002, 06002, 12002 and
18002 with the constraint that the 2
consecutive warnings may not be more than
2
CHAPTER II - RECONNAISSANC&ECOMMUNICATIONS
1. GENERAL satellite positions received at JTWC from
the Air Force Global Weather Central,
The Joint Typhoon Warning Center relies Offutt Air Force Base, Nebraska were timely
primarily on two reconnaissance platforms, for the 0800Z and 2000Z warnings in the
aircraft and satellites, to provide the Indian Ocean. As in 1974 and 1975, satellite
required fix data for tropical cyclone metwatch of the western North Pacific proved
warnings. In 1976 these two platforms pro- extremely useful in identifying areas of
vided 74.7% of the fixes used for tropical possible tropical cyclone formation, thus
cyclone warnings in the western North Pacific. reducing the number of aircraft investigative
Radar, synoptic data and extrapolation were flights. The Detachment 1, 1st Weather Wing
the basis for the remaining 25.3%. In the DMSP site on Guam was modified in February
Indian Ocean area of responsibility 89% of 1977 to receive and process data from NOAA
all warnings were based on satellite data. satellites.
Land radar also provides very useful
2. RECONNAISSANCE RESPONSIBILITY positioning data on well developed cyclones
AND SCHEDULING when in proximity (usually within 175 nm of
the radar site) of the Republic of the
Aircraft weather reconnaissance is per- Philippines, the Republic of China, Hong
formed in the JTWC area of responsibility by Kong, Japan (including the Ryukyu Islands),
the 54th Weather Reconnaissance Squadron (54 Korea, and Guam.
WRS). The squadron, presently equipped with
six WC-130 aircraft, is located at Andersen
Air Force Base, Guam. From July through 3. AIRCRAFT RECONNAISSANCE
October, augmentation by the 53rd Weather EVALUATION CRITERIA
Reconnaissance Squadron at Keesler Air Force
Base, Mississippi brings the total number of The following criteria are used to evalu-
available aircraft to nine. The JTWC recon- ate reconnaissance support to JTWC.
naissance requirements are provided daily
throughout the year to the Tropical Cyclcme
a. Six-hour fixes - To be counted as made
Aircraft Reconnaissance Coordinator (TCARC).
on time, a fix must satisfy the following
These requirements include area(s) to be
criteria:
investigated, tropical cyclone(s) to be fixed,
fix times, and forecast position of fix. In
accordance with CINCPACINST 3140.lM, “Usage ~ hr bef~~~ Fix must be made not earlier than
of reconnaissance assets in acquiring meteor- nor later than 1/2 hr after
ological data from aircraft, satellites and scheduled fix time.
land-based radar shall be at the discretion of
FLEWEACEN/JTWC Guam based on the following (2)Aircraft in area requested by
priorities: scheduled fix time, but unable to locate
(1) Alert flights and vortex or center center due to:
fixes as required for issuance of tropical
cyclone warnings in the Pacific area of res- (a) Cyclone dissipation; or
ponsibility; (b) Rapid acceleration of the
(2) Center or vortex fixes as required cyclone away from the forecast position.
for issuance of tropical cyclone warnings in
the Indian Ocean area of responsibility; (3) If Penetration not possible due
(3) Supplementary fixes; and to geographic or other flight restrictions,
(4) Synoptic data acquisition”. aircraft radar fixes are acceptable.
As in previous years, aircraft reconnais- b. Levied 6-hr fixes made outside the
sance provided direct measurements of height, above limite are evaluated as follows:
temperature, flight level winds, sea level
pressure, estimated surface winds (when (1)Early-fix is made within the
observable) and numerous additional parameters. interval from 3 hr to 1 hr prior to
These data provide the Typhoon Duty Officer scheduled fix times. However, no credit will
indications of changing cyclone characteristics, be given for early fixes made within 3 hr of
radius of cyclone associated winds and posi- the previous fix.
tion and intensity determinations. Another
important aspect of this data is its (2)Late-fix is made within the
availability for research in tropical cyclone interval from 1/2 hr to 3 hr after scheduled
analysis and forecasting. Aircraft recon- fix time.
naissance will become even more important in c. when 3 hr fixes are levied, they must
years to come when high-resolution tropical satisfy the same time criteria discussed above
cyclone dynamic steering programs will require in order to be classified as made on time.
a dense input of wind and temperature data. Three-hour fixes made that do not meet the
above criteria are classified as follows:
DMSP satellites and USAF ground sites
provide day and night coverage of the JTWC
(1) Early-fix is made within the
area of responsiblility. Interpretation interval from 1 1/2 hr to 1 hr prior to
of this satellite imagery provides cyclone scheduled fix time.
positions, and for daytime passes estimates
of storm inteneities are also made. This (2) Late-fix is made within the
year timely readouts were available at JTWC interval from 1/2 hr to 1 1/2 hr after
only for the 0000Z and 1200Z warnings. DMSP scheduled fix time.
3