====================== TYPHOON '98 ARCHIVES ====================== MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY NOVEMBER, 1998 (For general comments about the nature of these summaries, as well as information on how to download the tabular cyclone track files, see the Author's Note at the end of this summary.) *********************************************************************** NOVEMBER HIGHLIGHTS --> Two hurricanes form in Bay of Bengal / one makes landfall in India --> Three tropical storms affect southern Vietnam *********************************************************************** CORRECTIONS and ADDENDA to the OCTOBER and Earlier Summaries I have received from several persons e-mail pointing out some inaccuracies in the information presented in the October summary, as well as some additional and/or clarifying information for the October and earlier summaries. A thanks to all those who wrote and pointed out these items. (1) Relationship between NWP cyclones Alex and Zeb--John Wallace thought it should be mentioned that tiny Alex was absorbed by the larger and stronger Zeb. I was aware that Alex was indeed absorbed into Zeb but failed to explicitly mention that fact. (2) Rainfall in Texas resulting from NEP Hurricane Madeline--John Wallace also informed me that moisture carried northeast into Texas from Hurricane Madeline was responsible (at least in part) for some very heavy rainfall in the San Antonio area. A slow- moving cold front helped to trigger the rains, which amounted to 330-380 mm during the extended weekend. John also pointed out that the death toll attributed to the rains of Tropical Storm Charley in August has been placed at 21--a few more than the 17 reported in the August summary. (3) Information on Hurricane Georges--Juan Sebastian Lebron Delgado of Puerto Rico wrote to clarify that not all the information he'd sent me on Georges' effects came from the newspaper _El Nuevo Dia_. The interview with a Dominican consul was aired on radio, and some of the other information came from various television programs. Juan also mentioned a website which contains some detailed Georges rainfall amounts from Puerto Rico: (4) Correction to the NCDC website address for Hurricane Mitch--Gert van Dijken pointed out an error I'd made in reporting this site for information on Mitch. The correct address is: (NOT "htm") (5) Special "Mitch Fact Sheet" on the UK website--Julian Heming notified me that he'd prepared a special Fact Sheet on Hurricane Mitch on the website for the UK Meteorological Office. The URL is: (6) Boundary between Perth's and Darwin's AORs--Geoff Garden wrote to inform me that the boundary between the areas of warning responsi- bility of the Perth and Darwin TCWCs was 125E and not 129E as I'd reported. The boundary between Western Australia and the Northern Territory is indeed at 129E, but since the major population center of Darwin lies at about 131E, in order to allow a larger "margin of comfort" the Darwin TCWC's AOR extends 4 degrees westward along the Western Australian coast. The coastal area near 125E is extremely sparsely populated. (7) Additional tracking information for Mitch--Steve Young passed along a portion of a U. S. Navy track for Hurricane Mitch which includes some coordinates for the period when Mitch was overland and TPC/NHC had ceased issuing advisories. I am including the relevant portion of that track below. However, keep in mind that TPC/NHC ceased writing advisories when all indications were that there was no longer an identifiable surface circulation, so these positions may just reflect the central area of the weak, upper- level remnants of the circulation for at least a portion of this time frame. MITCH - Track from Nov 02/0000 UTC through 03/1200 UTC DATE TIME LAT LON MSW (1-min) -------------------------------------------------- 98 NOV 02 0000 16.2 N 92.6 W 25 98 NOV 02 0600 17.2 N 93.0 W 20 98 NOV 02 1200 17.9 N 93.4 W 20 98 NOV 02 1800 18.8 N 93.7 W 25 98 NOV 03 0000 19.2 N 93.4 W 25 98 NOV 03 0600 19.3 N 92.6 W 30 98 NOV 03 1200 19.3 N 92.0 W 30 *********************************************************************** ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for November: 1 hurricane NOTE: Much of the information presented below was obtained from the TPC/NHC discussion bulletins issued with every regular advisory. All references to sustained winds imply a 1-min averaging period unless otherwise noted. Hurricane Nicole (TC #14) 24 November - 2 December -------------------------- Hurricane Nicole evolved from a non-tropical LOW in the eastern Atlantic in late November. The Tropical Weather Outlook issued by TPC/NHC on the afternoon of 23 Nov mentioned that a low-pressure system about 525 nm west of the Canary Islands was moving southwest and showing some signs of convective organization. By early on 24 Nov the LOW was located about 625 nm west of the Canaries and displayed a tightly-wrapped convective band around the center. Dvorak intensity estimates were 35 kts so the LOW was upgraded to Tropical Storm Nicole in a special advisory at 1200 UTC. Shortly afterward a ship (call sign PFSJ) reported winds of 36 kts just north of the center, thereby confirming the satellite estimate. Nicole was located near the center of a large upper-level cyclone where shear was light. Convection was well-organized but was relatively shallow. Initially, Nicole was a small tropical storm with tropical storm force winds extending out only 50 nm. During the afternoon of the 24th an eye-like feature was seen intermittently in the very small convective cloud pattern accompanying Nicole. At 1800 UTC the same ship mentioned above reported winds to 58 kts northwest of the center, so the MSW was increased to 60 kts. Nicole continued moving to the west-southwest, gradually turning to a more westerly course. On 25 Nov the storm began to encounter westerly shear and steadily weakened. Ship reports indicated that the radius of tropical storm force winds had expanded considerably out to 125 nm in the northern semi-circle. Nicole was downgraded to a depression at 26/0900 UTC and was dropped from advisory status six hours later as the system was moving into a region with upper-level westerlies of 50-60 kts. However, the weak remnant survived this hostile shear and by early on the 27th was showing signs of regeneration. Advisories were re-initiated at 1200 UTC on 27 Nov and Nicole was re-classified as a tropical storm with 40-kt winds six hours later. The system developed an anticyclone at upper levels with good outflow and the MSW reached 50 kts by 0600 UTC on the 28th. Nicole had been moving westward but began to curve around to the west-northwest about this time. The recurvature continued and Nicole reached the westernmost point in its track about 1800 UTC when it was centered about 1000 nm east- southeast of Bermuda. Some upper-level shearing weakened the storm late on the 28th and early on the 29th, but as Nicole completed its recurvature and began moving to the northeast, upper diffluent flow helped to mitigate the effects of the shear and the cyclone began to slowly re-intensify once more. An eye-like feature began to appear on the afternoon of 29 Nov, and by 30/0000 UTC a ragged eye had become visible. With Dvorak T-numbers being 3.5 and 4.0, Nicole was upgraded to a hurricane at 0300 UTC. Around 1200 UTC on 30 Nov DMSP microwave data showed a rather well- defined eye surrounded by fairly deep convection. SSTs in the area were running about 1-2 degrees C above normal. Nicole reached its peak intensity of 75 kts MSW at 0000 UTC on 1 Dec a few hundred miles southwest of the Azores. The hurricane then accelerated to the north and passed west of the islands as it began to weaken. TPC/NHC issued the last advisory at 1500 UTC, downgrading Nicole to a tropical storm located about 150 nm west-northwest of the northwestern Azores. The storm continued rapidly northward and merged with a baroclinic zone and developing storm in the North Atlantic. It is not often that an Atlantic tropical cyclone exists on the charts during the month of December. The last such occurrence was Tropical Storm Karen in 1989. Karen formed at the very end of November in the Northwest Caribbean Sea, being named on the 30th, and meandered about in the same general area until it dissipated on 4 Dec. The last hurricane to exist in the Atlantic in December was Hurricane Lili of 1984. Lili evolved from a persistent subtropical storm which described a large loop in its track east and southeast of Bermuda. After it had transitioned into a hurricane, Lili moved for a couple of days in the general direction of the Leeward Islands where a Hurricane Watch was issued. The storm remained north of the islands and eventually dissipated near Hispaniola on Christmas Eve. *********************************************************************** NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180 Activity for November: No tropical cyclones *********************************************************************** NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180 Activity for November: 3 tropical storms NOTE: Most of the information on each cyclone's history presented in the narrative will be based upon JTWC's advisories, and references to winds should be understood as a 1-min avg MSW unless otherwise noted. However, in the accompanying tracking document I have made comparisons of coordinates with JMA (Japan) and the Philippines (PAGASA) when their positions differed from JTWC's by usually 40-50 nm or more. Also, as announced earlier in a separate posting, a column of 10-min avg MSW is included--the values being obtained from either PAGASA's or JMA's advisories. A special thanks to Michael V. Padua, owner of the Typhoon '98 webpage, for sending me the PAGASA tracks. Also some information, primarily on the pre-depression stages of the various cyclones, was taken from the Monthly Report of the RSMC, Darwin, Northern Territory, Australia. A special thanks to Peter Bate for forwarding that report to me. In the title line for each storm I plan to reference all the cyclone names/numbers I have available: JTWC's depression number and name (if any), JMA's tropical storm numeric designator, and PAGASA's name for systems forming in or passing through their area of responsibility. Tropical Storm Chip (TC-21W / TS 9812) 11 - 15 November --------------------------------------- A monsoon trough had become well-established across the South China Sea by early November, and a veritable parade of generally weaker tropical cyclones commenced and continued well into December. The first of these systems formed following a northeasterly monsoon surge associated with a subtropical ridge over China. JMA classified the system as a tropical depression at 0000 UTC on 11 Nov with the diffuse center estimated to be about 460 nm east-southeast of Ho Chi Minh City in Vietnam. The depression moved on a west-northwesterly course in the general direction of Vietnam. The depression reached tropical storm intensity around 12/0600 UTC and was named Chip by JTWC. A ship report of 35-kt winds over 100 nm from the center was the basis for upgrading the system to a tropical storm. The storm was centered about 325 nm east-southeast of Ho Chi Minh City at this time. Tropical Storm Chip reached a peak intensity of 50 kts at 1200 UTC on 13 Nov but significant vertical shear limited any further intensification. As it approached the Vietnamese coast Chip turned to more of a westerly course. The center of the storm barely reached the coast around 14/0000 UTC about 125 nm east-northeast of Ho Chi Minh City near Phan Rang. Chip then began to weaken and drifted south along the coast. The last JTWC advisory was issued at 0000 UTC on the 15th with a MSW of 25 kts reported. The lingering weak low-pressure area moved westward across the Gulf of Thailand, the Malaysian Peninsula, and emerged into the Andaman Sea where it began to re-develop. (See the section of this summary covering the North Indian Ocean basin.) Although weak, Tropical Storm Chip brought very heavy rains to portions of southern Vietnam--a region which had experienced heavy rainfall with extensive flooding during October. The rains of Chip were responsible for widespread flooding and at least 17 deaths. Tropical Storm Dawn (TC-22W / TS 9813) 18 - 20 November --------------------------------------- Another circulation had appeared in the South China Sea by 16 Nov adjacent to the southern Philippines. This new LOW became better organized following another northeasterly surge. JTWC issued a Formation Alert at 18/0030 UTC after receiving a ship report of 25-kt winds along the northern periphery of the circulation. The first warnings classifying the system as a tropical depression were issued at 0600 UTC on the 18th by both JMA and JTWC, placing the broad center roughly 300 nm east of Ho Chi Minh City. The depression moved on a west-northwesterly course and was upgraded to Tropical Storm Dawn at 0000 UTC on 19 Nov. Dawn was a rather large, monsoon depression-type of tropical cyclone. Gales extended out 150 nm to the west of the center and 130 nm elsewhere. The storm experienced considerable shear throughout its life and exhibited an exposed low-level center by the time it made landfall in Vietnam. Dawn reached the coast of Vietnam near Nha Trang--about 175 nm south of Da Nang--around 1800 UTC on 19 Nov. The weak storm moved inland and quickly dissipated. The Monthly Report from RSMC Darwin indicates that over 100 lives were lost due to the effects of Dawn--presumably from flooding. The Darwin Monthly Report implies that only JTWC classified Dawn as a tropical storm. Several agencies in the Northwest Pacific area issue warnings independently of each other. I simply do not have the time to examine all the warnings which may be issued--some are not always available to me--so I normally consult only warnings from JTWC, JMA, and PAGASA for the Northwest Pacific basin. In the case of Dawn, PAGASA did not issue warnings as the system formed west of their AOR. However, JMA (who is the RSMC for the NWP basin) did classify Dawn as a tropical storm (TS 9813) with a MSW (10-min) of 35 kts. Tropical Storm Elvis/Miding (TC-23W / TS 9814) 22 - 26 November ----------------------------------------------- A new LOW formed in the active monsoon trough to the east of the Philippine island of Mindanao on 20 Nov and tracked west-northwestward across the archipelago over the next three days. PAGASA initiated advisories on 22 Nov at 1800 UTC when the system was located in the vicinity of the Leyte Gulf about 400 nm southeast of Manila. The depression, named Miding, drifted west-northwestward and into the South China Sea. The system was upgraded to Tropical Storm Miding at 0000 UTC on 24 Nov when located about 275 nm southwest of Manila. (At this time JMA's MSW was 30 kts, and JTWC had not even initiated warnings--another good illustration of the uncertainties inherent in tropical cyclone intensity analysis from remote sensing.) Miding, which was a classic monsoon depression tropical cyclone, continued moving westward and had moved out of PAGASA's AOR by 1200 UTC. JTWC began issuing warnings at 0600 UTC upon receipt of a ship report of 20-kt winds (10-min avg) south of the center. JMA classified Miding as TS 9814 at 1200 UTC with 35-kt MSW (10-min). JTWC finally upgraded the system to Tropical Storm Elvis at 0000 UTC on 25 Nov after receiving a ship report of 45-kt winds. The 45-kt MSW reported in the first JTWC warning represents the peak intensity of Elvis. The storm existed in an environment of easterly shear and did not strengthen further. Tropical Storm Elvis continued on a general west-northwesterly course and made landfall on the Vietnamese coast about 75 nm south of Da Nang around 25/0000 UTC. The storm no doubt added to the already serious flooding problems in the region, but the author has not learned of any casualty figures directly associated with Tropical Storm Elvis. *********************************************************************** NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for November: 2 tropical cyclones of hurricane intensity NOTE: The tracking and intensity information for North Indian Ocean Basin tropical cyclones is based primarily upon operational warnings from the Joint Typhoon Warning Center of the U.S. Air Force and Navy (JTWC) on the island of Guam. For weaker systems not in warning status by JTWC, information gleaned from the twice-daily issuances of the Indian Meteorological Department (IMD) was used to complete the tracks. These bulletins usually give analyzed center positions at either 0300 or 0600 UTC and 1200 or 1500 UTC. The MSW are based on a 1-min averaging period, which is used by all U.S. civilian and military weather services for tropical cyclone warnings. For synoptic observations in the North Indian region, both 10-min and 3-min average winds are employed, but IMD makes no attempt to modify the Dvorak scale for estimating tropical cyclone intensity; hence, a 1-min avg MSW is implied. In the North Indian basin JTWC usually does not initiate warnings until a system is well-organized and likely to attain tropical storm status within 48 hours. In addition to the two cyclones discussed below, there was another tropical LOW in the Arabian Sea in mid-month which exhibited a somewhat well-organized appearance in satellite imagery, although it was quite small. The system tracked westward from the central Arabian Sea near 11.0 N, 64.0 E early on 11 Nov to a location off the Somalia coast near 9.5 N, 54.5 E by 14 Nov. Both JTWC and IMD mentioned this disturbance in their daily Tropical Weather Outlooks but neither classified it as a depression. Tropical Cyclone (TC-06B) 13 - 16 November -------------------------- A circulation was identified in the North Indian monsoon trough on 10 Nov near 10.0 N, 90.0 E. The system drifted slowly northwestward over the next few days. IMD first mentioned this system on 13 Nov when it was located in the west-central Bay of Bengal. By the 14th the LOW was approaching the upper-level ridge axis and a region of weaker vertical shear. Early on 14 Nov a period of rapid development ensued, and JTWC issued the first warning for a 55-kt tropical cyclone at at 0600 UTC centered about 250 nm southeast of Visakhapatnam in Andhra Pradesh state. The cyclone continued on its northwesterly course and steadily intensified. The storm made landfall about 25 nm southwest of Visakhapatnam around 1200 UTC on 15 Nov with the MSW estimated at 85 kts. Once inland the cyclone began to rapidly dissipate as it continued northwestward across the Indian subcontinent. At least two deaths were reported as well as extensive crop and property damage in Andhra Pradesh state. (This information taken from the RSMC Darwin Monthly Report.) Tropical Cyclone (TC-07B) 17 - 23 November -------------------------- After dissipating off the coast of Vietnam, the remnants of former Tropical Storm Chip moved westward across the extreme southern tip of Vietnam, the Gulf of Thailand, the Malaysian Peninsula, and emerged over the Andaman Sea on 17 Nov. The system was initially located in a region of strong vertical shear and was very slow to re-organize. JTWC issued three separate Formation Alerts for this system. The LOW had been moving westward along the periphery of an upper-level subtropical ridge to the north, but on the 18th its movement slowed and the disturbance began to track more to the northwest, gradually accelerating. It also was moving into a region of decreased vertical shear, and early on 20 Nov reached tropical cyclone status with 35-kt winds about 550 nm south of Calcutta. The cyclone continued to steadily intensify as it approached the west coast of India and gradually began to turn to the north. The storm passed about 200 nm east of Visakhapatnam around 21/1200 UTC. Peak intensity of 75 kts was reached about this time as the cyclone began to recurve toward the northeast. However, as the storm reached the upper reaches of the Bay of Bengal it began to encounter strong upper-level southwesterlies which quickly sheared the convection away from the low-level center. The cyclone began to rapidly weaken and was at best only a minimal tropical storm, possibly only a depression, as it made landfall along the Bangladesh coast about 50 nm west of Chittagong. A storm surge and flash flooding inundated many coastal communities in Bangladesh and more than 100 fishermen were reported missing. (This information taken from the RSMC Darwin Monthly Report.) Normally, whenever a cyclone moves from the Northwest Pacific basin into the North Indian Ocean basin, JTWC continues to apply the NWP cyclone number (and name if it were a named storm)--an example being Typhoon Linda of November, 1997. The connection of TC-07B with former Tropical Storm Chip perhaps was not quite as obvious. I have based my report of this connection upon the Monthly Report from the Darwin TCWC. Also, a gentleman who is a tropical cyclone enthusiast, Matthew Saxby of Canberra, Australia, sent me some of the JTWC Tropical Weather Outlooks and Formation Alerts (which I had somehow missed archiving) which support the connection between Chip and the Indian Ocean cyclone. (A special thanks to Matthew for bringing this matter to my attention.) *********************************************************************** SOUTH INDIAN OCEAN (SIO) - South Indian Ocean West of Longitude 90E Activity for November: No tropical cyclones *********************************************************************** AUSTRALIAN REGION (AUG) - From Longitude 90E Eastward to Longitude 160E Activity for November: 1 tropical cyclone of storm intensity The primary source of information for Australian Region tropical cyclones are the warnings and bulletins issued by the three TCWC's at Perth, Darwin, and Brisbane. Information gleaned from JTWC's warnings is used as a supplement for times when it was impossible to obtain Australian bulletins and for comparison purposes. Additionally, some information came from the Monthly Report of the RSMC at Darwin, Northern Territory. References to sustained winds should be understood as being based on a 10-min averaging period unless otherwise noted. Tropical Cyclone Alison (TC-04S) 8 - 13 November --------------------------------- The second early-season tropical cyclone in the Australian Region developed in a well-defined Near Equatorial Trough and shear line which had persisted over the South Indian Ocean for several months. A tropical LOW with a distinct cloud signature was evident to the northeast of Cocos Island as early as 5 Nov. The system was located near a ridge axis but there was sufficient vertical shear over the center to inhibit intensification. However, by 8 Nov the shear had relaxed enough to allow a separate outflow to form over the LOW and it intensified quite rapidly into Tropical Cyclone Alison. At 0400 UTC on the 8th the system was located about 130 nm northeast of Cocos Island and was moving to the south-southwest. Six hours later the MSW had reached 40 kts and Alison was christened. The cyclone passed only about 25 nm south of Cocos around 2200 UTC on 8 Nov. A 10-min sustained wind of 34 kts with gusts to 47 kts was reported from the island weather station (WMO 96996). Tropical Cyclone Alison moved on a fairly straight course in a southwesterly direction throughout most of its life. Peak MSW of 60 kts occurred on 9 and 10 Nov. (JTWC's estimated peak 1-min avg MSW of 70 kts is in excellent agreement with the Perth TCWC's peak 10-min avg MSW.) Alison continued on its southwesterly course and by 11 Nov moved through a weakness in the upper-level ridge, subsequently encountering stronger vertical shear and cooler SSTs. The cyclone steadily weakened during 11 and 12 Nov. Visible satellite imagery at 1030 UTC showed a tightly-wrapped exposed low-level circulation center. By 1300 UTC essentially all the deep convection had been sheared away to the southeast. Perth issued the last warning at 1600 UTC on the 12th, placing the weakening cyclone with 40-kt peak winds about 575 nm southwest of Cocos Island. JTWC issued one more warning (at 13/0000 UTC), tracking the weak center west-northwestward across 90E and into the South Indian Ocean basin. However, the system was rapidly falling apart and the author is not aware of any bulletins concerning Alison released by the TCWC's at La Reunion and/or Mauritius. *********************************************************************** SOUTHWEST PACIFIC (SWP) - South Pacific Ocean East of Longitude 160E Activity for November: No tropical cyclones *********************************************************************** EXTRA FEATURE In order to shorten the amount of typing in preparing the narrative material, I have been in the habit of freely using abbreviations and acronyms. I have tried to define most of these with the first usage in a given summary, but I may have missed one now and then. Most of these are probably understood by a majority of readers but perhaps a few aren't clear to some. To remedy this I developed a Glossary of Abbreviations and Acronyms which I first included in the July summary. Since this summary is considerably shorter than the previous two have been, I am repeating the glossary at the end of this issue following the Author's Note. *********************************************************************** AUTHOR'S NOTE: This summary should be considered a very preliminary overview of the tropical cyclones that occur in each month. The cyclone tracks (provided separately) will generally be based upon operational warnings issued by the various tropical cyclone warning centers. The information contained therein may differ somewhat from the tracking and intensity information obtained from a "best-track" file which is based on a detailed post-seasonal analysis of all available data. Information on where to find official "best-track" files from the various warning centers will be passed along from time to time. The track files are not being sent via e-mail. They can be retrieved in the following manner: (a) FTP to: hrd-type42.nhc.noaa.gov [140.90.176.206] (b) Login as: anonymous (c) For a password use your e-mail address (d) Go to "data" subdirectory (Type: cd data) (e) Set file type to ASCII (Type: ascii) (f) Transfer file (Type: get remote_file_name local_file_name ) (The files will be named with an obvious nomenclature--using November as an example: nov98.tracks) (g) To exit FTP, type: quit Both the summaries and the track files are standard text files created in DOS editor. Download to disk and use a viewer such as Notepad or DOS editor to view the files. The first summary in this series covered the month of October, 1997. If anyone wishes to retrieve any of the previous summaries, they may be downloaded from the aforementioned FTP site at HRD. The summary files are catalogued with the nomenclature: nov98.sum, for example. Back issues can also be obtained from the following websites (courtesy of Michael Bath, Michael V. Padua, and Tom Berg): (since January only) Another website where much information about tropical cyclones may be found is the website for the UK Meteorological Office. Their site contains a lot of statistical information about tropical cyclones globally on a monthly basis. The URL is: The preliminary storm reports for all the 1997 Atlantic and Eastern North Pacific tropical cyclones are available on the Tropical Prediction Center's website: . These reports include the analyzed best-track for each cyclone. The staff of JTWC is also working on an on-line version of their Annual Tropical Cyclone Report for 1997. It is still under construction, but the best-track files are already available for 1997 Northwestern Pacific and North Indian Ocean cyclones. The URL is: Prepared by: Gary Padgett E-mail: garyp@alaweb.com Phone: 334-222-5327 (nights & weekends) / 850-882-2594 (weekdays) *********************************************************************** GLOSSARY of ABBREVIATIONS and ACRONYMS AOML/HRD - Atlantic Oceanographic and Meteorological Laboratory/ Hurricane Research Division, located on Virginia Key, Miami, Florida, U.S.A. AOR - area of responsibility CDO - central dense overcast CPHC - Central Pacific Hurricane Center, Honolulu, Hawaii, U.S.A. FLW - flight level winds FTP - file transfer protocol IMD - India Meteorological Department (RSMC New Delhi, India) JMA - Japanese Meteorological Agency (RSMC Tokyo, Japan) JTWC - Joint Typhoon Warning Center, Guam kt - knot = 1 nautical mile per hour m - meter, or metre mb - millibar, numerically equivalent to hectopascal mm - millimeter MSW - maximum sustained wind(s) (either 1-min avg or 10-min avg) nm - nautical mile = 6076.12 feet or 1852.0 meters NPMOC - Naval Pacific Meteorological and Oceanographic Center, Pearl Harbor, Hawaii, U.S.A. PAGASA - Philippines' Atmospheric, Geophysical & Astronomical Services Administration RSMC - Regional Specialized Meteorological Centre SST - sea surface temperature STS - severe tropical storm (MSW greater than 47 kts) TC - tropical cyclone TCWC - Tropical Cyclone Warning Centre (generic term) TD - tropical depression TPC/NHC - Tropical Prediction Center/National Hurricane Center, Miami, Florida, U.S.A. TS - tropical storm WMO - World Meteorological Organization, headquartered at Geneva, Switzerland UTC - Universal Time Coordinated, equivalent to Greenwich Mean Time or Zulu (Z) *********************************************************************** ***********************************************************************