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Monthly Global Tropical Cyclone Summary June 2004 [Summaries and Track Data] [Prepared by Gary Padgett] |
MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY JUNE, 2004 (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.) ************************************************************************* JUNE HIGHLIGHTS --> Western Pacific extremely active with five typhoons--tropics quiet elsewhere ************************************************************************* ***** Feature of the Month for June ***** "MOZ-MIDGETS" AND "MED-CANES" During the summer (boreal) of 2003, I sent another one of my famous surveys to the members of an informal tropical cyclone discussion group of which I am a member. I also recently sent it to a few other persons in the tropical cyclone community. I intend to present the results of the survey as monthly features spread over several months, beginning with the May, 2004, summary. The survey consisted of ten multiple-choice questions dealing with various tropical or subtropical cyclone-related issues, and two or three questions will be considered each month. The persons responding to the survey are listed below. A special thanks to each for taking the time to respond to the questions. Michael Bath - New South Wales, Australia Bruno Benjamin - Guadeloupe, French West Indies Eric Blake - TPC/NHC, Miami, Florida, USA Pete Bowyer - Canadian Hurricane Centre, Halifax, Nova Scotia, Canada Kevin Boyle - Newchapel Observatory, Stoke-on-Trent, UK Jeff Callaghan - BoM, Brisbane, Queensland, Australia Simon Clarke - Brisbane, Queensland, Australia Tony Cristaldi - NWS Office, Melbourne, Florida, USA Roger Edson - University of Guam, USA Chris Fogarty - Canadian Hurricane Centre, Halifax, Nova Scotia, Canada James Franklin - TPC/NHC, Miami, Florida, USA Bruce Harper - Brisbane, Queensland, Australia Julian Heming - UK Meteorological Office, UK Rich Henning - Eglin AFB, Florida, USA/Also 53rd Weather Recon. Squadron Karl Hoarau - Cergy-Pontoise University, Paris, France Greg Holland - BoM, Australia Mark Kersemakers - BoM, Darwin, Northern Territory, Australia Mark Lander - University of Guam, USA Chris Landsea - AOML/HRD, Miami, Florida, USA Gary Padgett - Alabama, USA Michael Pitt - US Navy David Roberts - TPC/NHC, Miami, Florida, USA David Roth - NOAA/HPC, Maryland, USA Matthew Saxby - Queanbeyan, New South Wales, Australia Carl Smith - Queensland, Australia Phil Smith - Hong Kong, China John Wallace - San Antonio, Texas, USA Ray Zehr - Colorado State University, Ft. Collins, Colorado, USA For each of the survey questions, the format will be as follows: (1) the question as it appeared in the original survey (2) summary of the responses to each of the possible choices (3) some of the comments from various respondents Following this I will attempt to present an analysis of the issues plus interject my opinions on the subject. The monthly feature for June focuses on two questions concerning (usually) small, warm-core cyclones which are often seen over the Mozambique Channel and cooler waters of the eastern subtropical Atlantic, and on rare occasions in the Mediterranean Sea. And although the survey preceded the occurrence of the recent Brazilian cyclone (Catarina), this system exhibited similar characteristics to the Mediterranean Sea and Mozambique Channel cyclones. The two questions were related, but I distinguished between the systems of the Mozambique Channel and eastern subtropical Atlantic from those of the Mediterranean Sea because the former occur in recognized tropical cyclone basins and have often been classified operationally as tropical or subtropical cyclones, whereas this is not true for the Mediterranean cyclones. There were 28 persons who responded to the survey questions. For some questions, certain persons did not specify an answer, so the total number of votes might not always add up to 28. Also, in some cases the respondent was undecided between two of the choices. In those cases I assigned 1/2 vote to each of the two choices. A word about the comments included below: this article is extremely long as it is, and I could not possibly include all the comments which the various respondents made. I have selected certain ones which seem to cover the various issues well, as well as a few which cast a different slant on the question. Question #4 - Mozambique Channel and Atlantic Systems ----------------------------------------------------- (1) The question was: Occasionally, especially in the Mozambique Channel and the eastern subtropical Atlantic, small cyclones are seen which are completely non-frontal, with well-organized central convection, and often an eye, and these systems can be quite intense. Yet, the central convection is rather shallow and warm compared with classic tropical cyclones. Should these systems be classified as tropical or subtropical storms? (A) Tropical (B) Subtropical (2) Summary of Responses (A) Tropical: 12.5 votes - 50% (B) Subtropical: 12.5 votes - 50% (3) Some Comments Chris Fogarty (B): "Sounds like a polar-LOW type system with the convection being shallow. There's likely no well-formed anti- cyclone aloft, so I think something like this still belongs in the STS category." Chris Landsea (A): "I think these are true tropical cyclones." Dave Roberts (no choice): "If the forecaster is confident on actual core structure, then a choice should be made. If not, classification could be made based on genesis region. Either way, an advisory/ warning should be written on the system." David Roth (B): "They form under cold H5 cyclones, usually during the cold season, thus they fit the old definition (still found in Webster's) of a neutercane, or in the Hebert/Poteat paper, a ST cyclone Type B, beta." Eric Blake (B): "Subtropical as they are typically not deep warm core." John Wallace (B): "ST, this seems to be a path of least regret, and one that does not compromise the definition of 'tropicality'." Julian Heming (A): "If you tried to educate on the difference between STs and TCs (i.e., large gale radius, lack of deep central convection for ST), but then contravene this by defining this type of storm as ST, it will just cause further confusion. However, I would be wary of defining such systems as purely tropical when they form in areas where the formation mechanisms are very different to conventional tropical storms (e.g., the ones near the Canaries/ Morocco). I don't see why systems such as this in the Mozambique Channel should not be called 'tropical', though." Karl Hoarau (A): "TC, especially if the AMSU data from satellites shows a warm core and if the QuikScat data indicates that the strongest winds are near the center of the cyclone." Mark Kersemakers (A): "TC, as long as it's producing gales at the surface. There's nothing in the TC definition that talks about the depth of convection." Mark Lander (A): "As you know, I am a big advocate for classifying cyclones as tropical if they exhibit the classic features of an eye, convective ring (or eyewall), and--as you point out--a factor of isolation. The handful of cases of Med-canes falls into this bin. As part of classes in Dvorak analysis, I often sneak in a few pics of these small cyclones (side-by-side with pics of regular TCs), and no one ever recognizes the trick. I have seen enough of the Moz. Channel systems and others in the subtropics of the Pacific and North Atlantic that to me, they are unquestionably tropical in character, and little different from height-of-the-season real TCs. So many times, the odd ship or island that gets in one of these shows that the winds are there. On another topic, there is often a jaded view of "deep convection", especially here in the western North Pacific, where the eyewall tops and tops of MCSs are often in the -75 to -80 C range (or colder!). People see convection in a higher latitude cyclone that is say in the -40's C or so, and claim that the convection if not "deep". I like to point out that at -40 C the cloud tops are still near 35,000 ft! This would make for a decent thunderstorm in the mainland." Matthew Saxby (A): "If it looks, walks, and quacks like a duck.... besides, I doubt fussy points about depth of convection would matter much to any victim." Pete Bowyer (no choice): "Maybe there should simply be a spectrum going from A to Z, with A being purely tropical, and Z being purely extratropical...then the storm could be classified according to its location along the spectrum. Or better still, maybe an extended version of Bob Hart's phase space diagram could include these types of storms...and Mark Lander's midgets, etc." Phil Smith (A): "TC - the 'duck' argument applies." Tony Cristaldi (A): "From what I have seen, "Moz" midgets and "Kona LOWs" fit more of the classic definition of a warm-core tropical cyclone." Ray Zehr (B): "ST, unless they're over 26-plus C water--then they're midget TCs." Rich Henning (B): "If it is not over 80 F degree water...these systems usually rely on a sharp lapse rate (cold air aloft over luke- warm water to obtain similar thermodynamic potential through the temperature gradient between the ocean surface and tropopause). The purely tropical system now east of the Lesser Antilles (this was written 4 August 2003) is using a SST of approximately 84 F (29 C) and a tropopause height of ~130 mb where the temperature is approx- imately -70 C. The storms you are describing use SSTs often down around 72 F (22 C) with tropopause heights only around 300 mb (so the convection is capped out at only 30,000 feet or so). The 500-mb temperature in these systems is MUCH lower than what we see in the tropics in August." Question #5 - Mediterranean Cyclones ------------------------------------ (1) The question was: Rarely, systems very similar if not identical to those described in Question #4 above are seen in the Mediterranean Sea, often over considerably colder SSTs. Should the "Med-canes" be classed as: (A) Tropical (B) Subtropical (C) Some perhaps tropical, some subtropical (D) Non-tropical (E) Other (elaborate) (2) Summary of Responses (A) Tropical: 2.0 votes - 8% (B) Subtropical: 9.5 votes - 40% (C) Some TCs, others STCs: 5.0 votes - 21% (D) Non-tropical: 5.5 votes - 23% (E) Other: 2.0 votes - 8% (3) Some Comments Chris Fogarty (B): "Here I am thinking "hybrid", which is essentially a synonym for "subtropical cyclone" - agree? Hybrids have both tropical and extratropical characteristics." Chris Landsea (A): "I do think such systems are more similar to TCs than any other type of storm system. If these are produced by sensible & latent fluxes from the ocean (or Med. Sea in this case), then it should be the same dynamics, even if the SSTs are 15 C." Dave Roberts (D): " I think it is very possible to find an energy source during its developing stage that is dynamic/baroclinic in nature." David Roth (C): "Some perhaps tropical, some subtropical. If the convection is significantly deep (with tops colder than -40 C), there is little reason not to use the TC definition. Otherwise, they fit the neutercane, ST cyclone Type B, beta, definition nearly perfectly." John Wallace (B & D): "These systems do seem to derive much of their energy from warm-core processes, but on the whole they seem too different to consider "true" ST systems; they resemble strong "polar LOWs" more than STCs." Julian Heming (D): "Since the classical definition of areas of TC formation includes a prerequisite for warm SSTs, I don't think you can define such systems as tropical. However, whilst the distinction is fairly clear for Med-canes, it may be a bit more blurred for areas nearer to TC development belts." Karl Hoarau (D): "Non-tropical--they often form in winter." Mark Lander (A): "Well-developed Med-canes are certainly TCs by nearly all criteria one could apply to them. Even the objection recently raised that there has never been a record of sustained hurricane-force winds in them was silenced by Jack Beven's Med-cane in which I think a ship recorded an 82-kt sustained wind. If only to avoid the strangeness of saying that there is a hurricane in the Mediterranean in the winter (the preferred time for these things), then perhaps a special designation is appropriate, such as sub- tropical, or some other designator tailored for the region. But advisories from a TCWC (such as NHC) are appropriate." Michael Pitt (E): "I would go on a case-by-case basis to determine their nature." Phil Smith (C): "These seem to get more attention than perhaps any similar storms anywhere else in the world, probably because of their rarity, but also because of their sometimes impressive sat pic images. Dare one apply the "duck" argument to them?" Bruce Harper (E): "Not my call, but I'd like to think that a consistent/logical/agreed system can be devised. Bottom line: all severe weather systems should be classified, named and tracked so that they become visible to those needing to (a) warn, (b) be warned and (c) analyse overall risks and develop infrastructure design criteria, etc." Greg Holland (D): "Certainly not tropical." Rich Henning (B): "I think the same mechanisms are in place in the Med. Sea as we see in those systems described in (Question) #4, except the SSTs are even colder (approximately 65 or 68 F), with even colder conditions aloft initially generating the convection." Analysis and Gary's Opinion --------------------------- Regarding Question #4, in addition to the well-known Mozambique Channel higher-latitude cyclones, I had in mind such eastern Atlantic systems as the early stages of Tropical Storm Nicole in 1998 (with Tropical Storm Peter of 2003 being a later example). When Nicole was initially classified as a tropical storm, it was very small and exhibited quite shallow convection. The storm, however, later became a hurricane. As can be seen from the survey results, respondents were split 50-50 on whether to call these systems tropical or subtropical. I voted for 'tropical', but admittedly it is a tough call. Some of these continue to evolve into more of a classic tropical cyclone while others remain as fairly shallow convective systems. However, if tropical/subtropical cyclone warnings are issued for them (such as La Reunion does and NHC has started doing), then whether they're called tropical or subtropical storms isn't of such paramount importance. In either case they should be added to the appropriate Best Track database and flagged as to their classification. As for the Mediterranean Sea cyclones, things get even fuzzier. Some of these systems (such as the September ones) have formed over waters probably as warm as 22-24 C and are in essence no different from some Atlantic tropical cyclones forming over similar SSTs, e.g., Ivan and Karl of 1980. At the other extreme some have formed in January over 12-14 C SSTs. It seems likely that these have much in common with polar LOWs. Others fall in between and probably could be comfortably classified as subtropical cyclones. The good thing about these systems is that they're isolated--they are confined to the Mediterranean Sea and are not likely to be contenders for influencing the tropical cyclone statistics of other basins (primarily the Atlantic). Perhaps until the day comes when more studies of these systems can be made, the best plan might be to just call them "Mediterranean cyclones", or "Mediterranean convective cyclones" (another type of MCC!). With regard to operational warnings, whatever warning format and nomenclature provides adequate protection to coastal populations and marine interests in the region should be acceptable to everyone else. The responses to these questions, however, bring up a very interesting side issue: the oft-quoted 80-degree Fahrenheit or 26.7-degree Celsius SST threshold for tropical cyclone formation. It was surprising to me to learn that even some U. S. researchers and meteorologists seem to think that a system must form over 80+ F water to be considered a tropical cyclone. On the other hand, some are comfortable calling a Mediterranean cyclone forming over 15 C SSTs a tropical cyclone if it appears to be driven completely by sensible and latent heat fluxes from the ocean. These differences of opinion drive home a point I tried to make in my comments in the May monthly feature about subtropical storms, and that is the lack of very detailed and comprehensive definitions to such terms as tropical cyclone, subtropical cyclone, front, etc. I know of no official definition of a 'tropical cyclone' in any basin which specifies that it must form over some particular SST threshold, have a very tight wind center, exhibit anti-cyclonic outflow aloft, or have convection of some particular height or cold cloud tops of some parti- cular degree of coldness. Yet, these things seem to influence what a given person may regard as necessary for classifying a system as a tropical cyclone. TPC/NHC has regularly classified systems forming over sub-26 C water as tropical cyclones for almost a third of a century. And it is easy to see why. SSTs of 26 C or higher cover much of the North Atlantic south of latitude 40N during the late summer and early autumn, and in particular the western Atlantic waters can be quite warm in the Gulf Stream. Systems of definite baroclinic origin can spawn over these waters at subtropical latitudes and either slowly or quickly evolve into classic tropical cyclones. One of the most famous examples is Hurricane Diana of September, 1984, which started as a frontal wave and in less than four days was a Category 4 hurricane. Diana was directly over the Gulf Stream, but similar transformations (usually slower and not as intense) have occurred over marginal 26 C water, and no one would deny these tropical cyclone status. So when another baroclinic disturbance a little further to the east transforms into an essentially identical system over 24 or 25 C SSTs, the common sense thing to do is to classify it as a tropical cyclone. And so forth when another development occurs over 22 or 23 C water. As Rich Henning and David Roth have pointed out, these systems usually rely on a steeper lapse rate than that normally found in the tropics to support the convection. Chris Landsea has some information on this topic in the Frequently Asked Questions (FAQ) document on HRD's website: http://www.aoml.noaa.gov/hrd/tcfaq/A16.html> The empirical 26 C SST treshold was first discussed by Erik Palmen after a study in the late 1940s. This threshold seems to hold for regions with vertical temperature profiles typical of the tropical oceanic belts. The average lapse rate over tropical oceans is not particularly all that steep, and the massive quantities of water vapor needed to provide moist conditional instability generally require SSTs of 26 C or greater. But when conditions conspire to create a much steeper lapse rate (upper-level cold LOWs or strong surface sensible heating), the physical processes which drive deep tropical cyclones can operate over SSTs lower than the empirical 26 C threshold. However, just where to draw the line is a difficult question to answer. One complicating factor in the minds of many is the existence of the polar LOWs (sometimes called Arctic cyclones in the Northern Hemisphere). At least some of these storm systems seem to be non-frontal and have usually quite shallow convection, but also have weak warm cores and are quite similar to tropical cyclones in visual appearance in satellite imagery. They usually form in winter when frigid Arctic air masses move out over open water which is very cold, but still above freezing, leading to strong surface heating. This in turn sets up a very steep lapse rate in the lower levels, making the air convectively unstable. (Small systems of this type are also sometimes noted over the Black Sea and the North American Great Lakes.) Several years ago David Roth and I had a discussion about all these convective systems of higher-latitude origin. David drew a distinction between those in which the atmospheric instability was primarily at lower levels and caused by the juxtaposition of cool/cold air masses over relatively warmer waters (e.g., polar LOWS and maybe the wintertime Mediterranean cyclones), and those in which the instability of the atmosphere was enhanced at upper levels by cold pools of air and/or a lower tropopause (e.g., the typical Atlantic tropical cyclones forming in subtropical latitudes and perhaps some of the warmer season Mediterranean cyclones). Historically, tropical cyclones have been considered to be driven primarily by latent heat release, while it seems that in polar LOWs, with the much-reduced amount of water vapor available, strong surface (sensible) heating is what provides the instability for the convection with latent heating providing only a boost at rather low levels in the atmosphere. For systems over "lukewarm" SSTs in the 22-26 C or so range, cold air aloft no doubt enhances the convection, but it seems likely that latent heat release is still the major source of energy driving the circulation, so in my opinion these systems (including cyclones like the recent Catarina) are best considered tropical cyclones. However, for systems like some of the wintertime "Med-canes" over 12-14 C water, it does seem rather revolutionary to call them 'tropical cyclones'. Perhaps such cyclones represent an approximate 50-50 contribution to their energy budgets by both latent heat release and sensible heating at the surface. I'll conclude with the same thrust that I made in last month's feature. Regardless of how these systems are classified, whether they are named or not, and the style of warnings issued, the bottom line is that they should have warnings issued which will help to minimize loss of life and mitigate damage as much as possible. However, a secondary (but still very important) goal should be the establishment of a reliable and consistent global tropical cyclone historical database with as much "signal noise" reduction as possible. And, not meaning to offend anyone, but I personally think that this goal is one every forecaster and researcher in the tropical cyclone community should be concerned with. ************************************************************************* ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for June: No tropical cyclones ************************************************************************* NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180 Activity for June: No tropical cyclones Northeast Pacific Tropical Activity for June -------------------------------------------- No tropical depressions or storms formed in the Eastern North Pacific during June, but one tropical disturbance deserves mention. During the early days of the month, a large, broad area of disturbed weather formed in the Gulf of Tehuantepec and moved slowly west-northwestward for several days in close proximity to the southern coast of Mexico. From around the 6th to the 8th of June the system appeared slightly better organized with the potential to develop into a tropical depression, but convection had diminished significantly by the afternoon of 8 June. Due to the system's close proximity to the Mexican coastline, the Tropical Weather Outlooks from TPC/NHC emphasized the threat of heavy rainfall and possible flooding in the mountainous region. ************************************************************************* NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180 Activity for June: 4 typhoons 1 super typhoon Sources of Information ---------------------- Most of the information presented below is based upon tropical cyclone warnings and significant tropical weather outlooks issued by the Joint Typhoon Warning Center of the U. S. Air Force and Navy (JTWC), located at Pearl Harbor, Hawaii. In the companion tropical cyclone tracks file, I normally annotate track coordinates from some of the various Asian warning centers when their center positions differ from JTWC's by usually 40-50 nm or more. All references to sustained winds imply a 1-minute averaging period unless otherwise noted. Michael V. Padua of Naga City in the Philippines, owner of the Typhoon 2000 website, normally sends me cyclone tracks based upon warnings issued by the Japanese Meteorological Agency (JMA) and the Philippines' Atmospheric, Geophysical & Astronomical Services Administration (PAGASA). Also, Huang Chunliang of Fuzhou City, China, sends data taken from synoptic observations around the Northwest Pacific basin. A very special thanks to Michael and Chunliang for the assistance they so reliably provide. In the title line for each storm I have referenced all the cyclone names/numbers I have available: JTWC's depression number, the JMA-assigned name (if any), JMA's tropical storm numeric designator, and PAGASA's name for systems forming in or passing through their area of warning responsibility. Northwest Pacific Tropical Activity for June -------------------------------------------- The monsoon trough became well-established over Western Pacific waters as an active phase of the Madden-Julian Oscillation pushed through, giving birth to no less than five typhoons. And all the cyclones had rather significant effects on populated areas in the form of heavy rainfall and/or strong winds. Typhoon Dianmu intensified into a very strong super typhoon with JTWC estimating the peak intensity at 155 kts. Reports follow on all the cyclones, authored by Kevin Boyle, except for Typhoon Tingting, which I wrote up. Also, much meteorlogical data was supplied by Huang Chunliang of Fuzhou City, Fujian Province, China. Chunliang also sent me (thanks!) some statistics on early NWP seasons. The last time that five or more tropical cyclones formed in the month of June was 1961 when there were six. In addition, the formation of eleven numbered tropical cyclones was the first such occurrence since 1971, when there were also eleven. TYPHOON CONSON (TC-07W / TY 0404 / FRANK) 4 - 11 June ---------------------------------------------- Conson: contributed by Vietnam, is a picturesque place in Haihung Province, consisting of a mountain, pine forest, streams, pagodas and many historical monuments A. Introduction --------------- Typhoon Conson was the second tropical cyclone of the year to form in the South China Sea. It meandered close to Luzon for a day or so before accelerating northeastward and reaching a peak intensity of 95 kts, just short of major typhoon status. After threatening Taiwan, Conson passed over the southern Japanese islands before becoming extratropical over Honshu. B. Storm Origins ---------------- Typhoon Conson started as an area of deep convection approximately 420 nm south-southeast of Hong Kong. Animated multi-spectral satellite imagery revealed a well-defined LLCC in association with this suspect area. It was first mentioned in JTWC's STWO at 0200 UTC on 4 June with poor potential for development. With a reasonably favourable environment to work in, the potential was raised to fair at 02/0600 UTC, and then upped to good at 04/1500 UTC. The first warning on Tropical Depression 07W followed at 1800 UTC with the system centred 260 nm west of Manila, Philippines. Tropical Depression 07W meandered during the 5th roughly 250 nm or so west-northwest of Manila. It moved in a sort of loop-de-loop fashion, first towards the southwest and west before ending up on a slow eastward drift. Convection increased, mainly in the southern quadrants of the storm. Based on CI estimates of 30 and 35 kts, the system was upgraded to a minimal tropical storm at 05/1200 UTC. At the same time, PAGASA initiated warnings on the developing tropical system, christening it Tropical Depression Frank. Strengthening continued as Tropical Storm 07W/Frank began to curve onto a more northeasterly track with the MSW reaching 50 kts at 06/0600 UTC. The slow northeasterly heading took the cyclone as close as 160 nm west-northwest of Manila at 1200 UTC. C. Synoptic History ------------------- The latest prognosis indicated that a ridge over the central Philippines was expected to build and gradually push the tropical cyclone northward into the vicinity of Taiwan. This was to be the case, but movement during the first part of the 7th was rather slow. At 0000 UTC on 7 June the newly-named (by JMA) Tropical Storm Conson lay 360 nm south-southwest of Kaosiung, Taiwan. Conson began to intensify more significantly and became a typhoon at 07/1800 UTC as it began to move at a faster pace towards the north. At 08/0000 UTC Typhoon Conson/Frank was moving north at 8 kts with 65-kt peak sustained winds and located approximately 400 nm south- southwest of Taipei, Taiwan. Strengthening continued and the MSW reached 90 kts at 08/1800 UTC, a 10-kt increase for the 0600 UTC and 1200 UTC warnings, plus 5 kts during the next six hours. Animated infrared satellite imagery revealed a well-defined 8-nm diameter eye which became irregular and had expanded a little to 15 nm by 1800 UTC. The typhoon turned to a north-northeasterly to northeasterly heading which was to ultimately cause the storm (thankfully) to side-step Taiwan and spare the island the strongest winds. The MSW of Conson was still at 90 kts at 09/0000 UTC, by which time it was centred 235 nm south of Taipei and moving northeastward at 11 kts. Satellite imagery revealed that the eye had faded somewhat, but it gradually reappeared during the morning and became an obvious feature again by 09/1200 UTC. Infrared enhancement revealed a warmer eye temperature at the time Conson reached its maximum intensity of 95 kts, and this was maintained for another six hours as the typhoon continued northeastward over the warm waters of the Kuroshio Current. After 0000 UTC on 10 June Typhoon Conson began to weaken quite quickly and take on extratropical characteristics as it passed 35 nm northwest of Okinawa at 10/0600 UTC. Microwave imagery at 10/1200 UTC revealed a partially-exposed LLCC on the southern edge of the deep convection. By this time the MSW had dropped to 65 kts and Conson continued northeast- ward towards Japan at almost 20 kts. It was downgraded to a tropical storm at 1800 UTC, and extratropical transition was complete the next day at 11/0600 UTC, the time of the final warning issued by JTWC. Conson was then moving northeastward at 26 kts, being located 155 nm southwest of Kyoto, Japan, with the MSW estimated at 40 kts. The last reference to the ex-Conson low was in the 14/1200 UTC JMA bulletin when the system was approaching the Dateline. The peak 10-min avg MSW and minimum CP estimated by JMA were 75 kts and 960 mb, respectively. Among the Asian TCWCs, NMCC's estimated peak MSW of 80 kts was the highest. D. Meteorological Observations ------------------------------ The information in this section was sent by Huang Chunliang--a special thanks to Chunliang for sending the data. (1) Rainfall ------------ (a) Philippines --------------- 0000 UTC 5 June - 0000 UTC 6 June WMO 98531 San Jose (12.4N, 121.0E, Alt 3 m) 154.6 mm 0000 UTC 6 June - 0000 UTC 7 June WMO 98426 Subic Bay (14.8N, 120.3E, Alt 19 m) 230.0 mm WMO ----- Clark AB (15.2N, 120.6E, Alt 155 m) 135.0 mm WMO 98324 Iba (15.3N, 120.0E, Alt 5 m) 221.4 mm 0000 UTC 7 June - 0000 UTC 8 June WMO 98324 Iba (15.3N, 120.0E, Alt 5 m) 112.4 mm (b) Okinawa ----------- (09/0000 UTC - 10/0000 UTC) WMO 47936 Naha (26.2N, 127.7E, 28 m) 212.5 mm WMO 47918 Ishigakijima (24.3N, 124.2E, Alt 7 m) 204.5 mm WMO 47927 Miyakojima (24.8N, 125.3E, Alt 41 m) 107.0 mm (c) Taiwan ---------- (08/1600 UTC-09/1600 UTC) CWB Station ID County Rainfall ------------------------------------ C1U68 Ilan 262.5 mm C0U64 Ilan 245.5 mm C1U67 Ilan 181.5 mm C1U69 Ilan 163.0 mm Note: The 24-hr rainfall accumulations recorded in Ilan County can be considered as the storm totals. (d) Japan (Kyushu) ------------------ (10/0000 UTC - 11/0000 UTC) WMO 47837 Tanegashima (30.7N, 131.0E, Alt 18 m) 277.5 mm WMO 47909 Naze (28.4N, 129.5E, Alt 7 m) 130.0 mm WMO 47830 Miyazaki (31.9N, 131.4E, Alt 9 m) 117.0 mm (2) Wind Observations --------------------- Miyakojima, Okinawa (ROMY WMO47927 24.8N 125.3E Alt 40 m) ----------------------------------------------------------- Peak sustained wind: 57 kts (SSW) [09/1900Z] Peak gust: 100 kts (SW) [09/1850Z] Another sustained wind: 52 kts (SSW) [09/1850Z] Kumejima, Okinawa (ROKJ WMO47929 26.3N 126.8E Alt 4 m) -------------------------------------------------------- Peak sustained wind: 52 kts (SE) [10/0200Z] Peak gust: 89 kts (SE) [10/0155Z] Ishigakijima, Okinawa (ROIG WMO47918 24.3N 124.2E Alt 6 m) ------------------------------------------------------------ Peak sustained wind: 49 kts (NNW) [09/1540Z] Peak gust: 82 kts (N) [09/1520Z] Naha, Okinawa (---- WMO47936 26.2N 127.7E Alt 28 m) ----------------------------------------------------- Peak sustained wind: 32 kts (S) [10/0250Z] Peak gust: 54 kts (S) [10/0246Z] Nago, Okinawa (---- WMO47940 26.6N 128.0E Alt 6 m) ---------------------------------------------------- Peak sustained wind: 31 kts (S) [10/0530Z] Peak gust: 52 kts (S) [10/0528Z] Tarama, Okinawa (---- JMA93061 24.7N 124.7E Alt 16 m) ------------------------------------------------------- Peak sustained wind: 74 kts (NW) [time unknown] Another sustained wind: 58 kts (ENE) [09/1640Z] Naze, Kagoshima (---- WMO47909 28.4N 129.5E Alt 3 m) ------------------------------------------------------ Peak sustained wind: 27 kts (S) [time unknown] Peak gust: 75 kts (SE) [10/1223Z] Yakushima, Kagoshima (RJFC WMO47836 30.4N 130.7E Alt 36 m) ------------------------------------------------------------ Peak sustained wind: 48 kts (N) [10/2000Z] Peak gust: 72 kts (NNE) [10/1949Z] More gusts: 59 kts (NNE) [10/1910Z]; 68 kts (N) [10/1950Z] Aburatsu, Miyazaki (---- WMO47835 31.6N 131.4E Alt 3 m) --------------------------------------------------------- Peak sustained wind: 42 kts (NNE) [time unknown] Peak gust: 67 kts (NNE) [10/2207Z] Tanegashima, Kagoshima (---- WMO47837 30.7N 131.0E Alt 17 m) -------------------------------------------------------------- Peak sustained wind: 35 kts (NNW) [time unknown] Peak gust: 79 kts (N) [10/2036Z] Another gust: 58 kts (NE) [10/2000Z] Kagoshima, Kagoshima (---- WMO47827 31.6N 130.6E Alt 4 m) ----------------------------------------------------------- Peak sustained wind: 19 kts (NNE) [time unknown] Peak gust: 39 kts (NNE) [10/1949Z] Miyazaki, Miyazaki (---- WMO47830 31.9N 131.4E Alt 9 m) --------------------------------------------------------- Peak sustained wind: 16 kts (SW) [time unknown] Peak gust: 31 kts (N) [10/2131Z] Shimizu, Kochi (---- WMO47898 32.7N 133.0E Alt 31 m) ------------------------------------------------------ Peak sustained wind: 26 kts (W) [time unknown] Peak gust: 61 kts (SE) [time unknown] Another gust: 59 kts (SE) [11/0300Z] Murotomisaki, Kochi (---- WMO47899 33.3N 134.2E Alt 185 m) ------------------------------------------------------------ Peak sustained wind: 59 kts (ESE) [time unknown] Peak gust: 76 kts (SE) [time unknown] Another gust: 62 kts (SE) [11/0410Z] D. Damage and Casualties ------------------------ There were no reports of damage or casualties associated with Typhoon Conson. (Report written by Kevin Boyle with significant contributions by Huang Chunliang) TYPHOON CHANTHU (TC-08W / TY 0405 / GENER) 7 - 15 June ---------------------------------------------- Chanthu: contributed by Cambodia, is a type of flower A. Introduction --------------- Typhoon Chanthu was the second significant tropical cyclone in June and the first of the year to adopt a straight-runner track through the Philippines, across the South China Sea en route to Vietnam. B. Storm Origins ---------------- At 0600 UTC on 5 June an area of convection developed and persisted roughly 360 nm east-southeast of Yap. In response to this development JTWC included this new suspect area in their routine STWO. Animated multi-spectral satellite imagery revealed disorganized deep convection about a weak LLCC. An upper-level analysis indicated weak diffluence and light vertical wind shear and the potential for development was assessed as poor. It was upgraded to fair status at 15/1200 UTC (and the disturbance relocated to a position 290 nm east-southeast of Yap) after convection consolidated over the associated LLCC. However, the disturbance was no longer considered a suspect area at 06/0600 UTC and was dropped from JTWC's STWOs. The regeneration of the disturbance at 0600 UTC on 7 June prompted JTWC to once again mention the system in their regular STWOs. The potential for development was reassessed as poor. Multi-spectral imagery showed sporadic deep convection occurring over a developing LLCC, which was at this time located 210 nm east of Koror. The development potential was upgraded to fair at 08/0030 UTC, and then raised to good. Since the time of its re-introduction the suspect area had been really motoring westward and was located only 50 nm southeast of Dapa, Philippines, deep within PAGASA's territory at 08/2000 UTC--the time that JTWC issued an TCFA. PAGASA had named the system Tropical Depression Gener at 1200 UTC on the 7th when bulletins were initiated. C. Synoptic History ------------------- The first JTWC warning was issued at 0000 UTC on 9 June with the system centred 430 nm southeast of Manila and about to make landfall on southern Leyte Island. TC-08W/Gener began its career as a 40-kt tropical storm, but only a 5-kt increase in MSW had occurred by late on the 9th. By the end of the first day of its existence, TS-08W/Gener had completed its journey across the Philippine Archipelago and was about to cross into the South China Sea. JTWC's Prognostic Reasoning message correctly predicted that TS-08W/Gener's intensity would remain constant during its passage across the Philippines, and forecast strengthening as the cyclone moved west through an area of low shear and warmer SSTs in the South China Sea. Tropical Storm Gener continued its brisk west to west-northwesterly movement along the southwest periphery of the subtropical ridge and its associated tropical easterly flow. At 10/0000 UTC the system was located 190 nm south-southwest of Manila. Gener stuttered a little as the MSW fluctuated between 40-45 kts and the convection became somewhat disorganized for awhile. Although QuikScat imagery showed a well-defined LLCC, enhanced infrared animations showed a partially-exposed centre with cycling convection. During the day Tropical Storm 08W/Gener slowed, and by 1800 UTC was moving west-northwestward at 7 kts. At 10/1800 Tropical Storm 08W was named Chanthu after JMA finally upgraded the system to tropical storm intensity. Chanthu was centred some 740 nm southeast of Hanoi, Vietnam, and moving west-northwestward at a faster pace again with 45-kt winds. Now that it was moving over the warm waters of the South China Sea, strengthening began. By 11/1800 UTC the MSW had risen to 60 kts, and although poleward outflow was decreasing, animated enhanced infrared imagery indicated that the equatorward exhaust was improving slightly. Chanthu reached typhoon status at 12/0000 UTC while located approximately 540 nm southeast of Hanoi, Vietnam. Moving westward at 13 to 15 kts, it continued to intensify, reaching a peak of 75 kts at 12/0600 UTC. At this time Chanthu was located 200 nm southeast of Hue, Vietnam. Typhoon Chanthu made landfall near Qui Nhon, Vietnam, at 12/1200 UTC with a MSW of 70 kts. The storm weakened quickly as it moved further inland. Chanthu was downgraded to a 55-kt tropical storm at 12/1800 UTC, and then to a tropical depression the next day at 0600 UTC. The final warning was issued by JTWC at 13/0600 UTC, locating the center 180 nm southwest of Hue, Vietnam. The remnants of Typhoon Chanthu lingered for a few days as it slowly moved northwestward across Southeast Asia. The circulation was barely discernible in satellite imagery by the 15th. The minimum CP estimated by Japan was 970 mb. JMA, NMCC, the Central Weather Bureau of Taiwan and the Thai Meteorological Department all classified Chanthu as a 65-kt typhoon at its peak. However, the HKO did not upgrade Chanthu to typhoon status, instead estimating the peak intensity at 55 kts (10-min avg). D. Meteorological Observations ------------------------------ The following meteorological observations were all sent by Huang Chunliang. A special thanks to Chunliang for sending the information. (1) Rainfall Observations from Vietnam -------------------------------------- Station WMO ID Lat Lon Alt (m) Rain (mm) Time Period (UTC) ----------------------------------------------------------------------- Quy Nhon * 48870 13.8N 109.2E 6 238.9 11/1200 - 12/1200 Hue 48852 16.4N 107.6E 9 124.3 11/1200 - 12/1200 * - very near where Chanthu made landfall (2) Rainfall Observations from Thailand --------------------------------------- Station WMO ID Lat Lon Alt (m) Rain (mm) Time Period (UTC) ----------------------------------------------------------------------- Khlong Yai 48501 11.8N 102.9E 4 140.2 13/0000 - 14/0000 Ubon R. * 48407 15.3N 104.9E 127 110.5 13/0000 - 14/0000 Bua Chum 48418 15.3N 101.2E 50 106.8 13/0000 - 14/0000 Ubon R. * 48407 15.3N 104.9E 127 115.2 13/0600 - 14/0600 Bua Chum 48418 15.3N 101.2E 50 111.3 13/0600 - 14/0600 Surin 48432 14.9N 103.5E 147 192.6 13/0600 - 14/0600 Tha Tum 48416 15.3N 103.7E 129 112.1 13/0600 - 14/0600 Surin 48432 14.9N 103.5E 147 194.1 13/1200 - 14/1200 Surin 48432 14.9N 103.5E 147 140.6 13/1800 - 14/1800 Phitsanulok 48378 16.8N 100.3E 45 112.2 13/1800 - 14/1800 Phitsanulok 48378 16.8N 100.3E 45 121.1 14/0000 - 15/0000 Ranong 48532 10.0N 98.6E 8 115.8 14/0000 - 15/0000 Kosumphisai ----- 16.2N 103.1E 154 101.1 14/0000 - 15/0000 Phitsanulok 48378 16.8N 100.3E 45 131.5 14/0600 - 15/0600 Ranong 48532 10.0N 98.6E 8 126.5 14/0600 - 15/0600 Nong Khai 48352 17.9N 102.7E 175 121.6 14/0600 - 15/0600 Nong Khai 48352 17.9N 102.7E 175 135.6 14/1200 - 15/1200 Uttaradit 48351 17.6N 100.1E 64 148.5 14/1200 - 15/1200 Ranong 48532 10.0N 98.6E 8 114.2 14/1200 - 15/1200 Nong Khai 48352 17.9N 102.7E 175 134.3 14/1800 - 15/1800 Uttaradit 48351 17.6N 100.1E 64 180.6 14/1800 - 15/1800 Ranong 48532 10.0N 98.6E 8 108.6 14/1800 - 15/1800 Nong Khai 48352 17.9N 102.7E 175 126.9 15/0000 - 16/0000 Uttaradit 48351 17.6N 100.1E 64 193.0 15/0000 - 16/0000 Ranong 48532 10.0N 98.6E 8 114.0 15/0000 - 16/0000 Nan 48331 18.8N 100.8E 201 143.5 15/0000 - 16/0000 Phrae 48330 18.2N 100.2E 162 119.0 15/0000 - 16/0000 Uttaradit 48351 17.6N 100.1E 64 212.7 15/0600 - 16/0600 Ranong 48532 10.0N 98.6E 8 108.0 15/0600 - 16/0600 Nan 48331 18.8N 100.8E 201 216.7 15/0600 - 16/0600 Phrae 48330 18.2N 100.2E 162 197.3 15/0600 - 16/0600 Nan 48331 18.8N 100.8E 201 211.9 15/1200 - 16/1200 Phrae 48330 18.2N 100.2E 162 170.3 15/1200 - 16/1200 Phrae 48330 18.2N 100.2E 162 167.2 15/1800 - 16/1800 * - full name of station is Ubon Ratchathani (3) Rainfall Observations from the Philippines ---------------------------------------------- Station WMO ID Lat Lon Alt (m) Rain (mm) Time Period (UTC) ----------------------------------------------------------------------- Roxas 98538 11.6N 122.8E 4 150.2 09/0000 - 10/0000 Iloilo 98637 10.7N 122.6E 8 117.0 09/0000 - 10/0000 E. Damage and Casualties ------------------------ According to a news report, Typhoon Chanthu killed seven people and left five persons injured. Five fishermen died when their boat sank off the coast of Binh Dinh province while another was crushed in a separate incident as strong winds forced two boats against the dock. Seven fishermen were reported missing. The typhoon damaged or destroyed more than 180 houses in Binh Dinh province. No damage estimates are available at the time of this writing. (Report written by Kevin Boyle with significant contributions by Huang Chunliang) SUPER TYPHOON DIANMU (TC-09W / TY 0406 / HELEN) 12 - 23 June ---------------------------------------------- Dianmu: contributed by China, is the 'Mother of the Lightning', the goddess in charge of thunder and lightning A. Introduction --------------- Dianmu was the third of five significant tropical cyclones during June and also the third super typhoon of the year. It formed in the vicinity of Yap, rapidly reaching a peak intensity of 155 kts before weakening and making landfall in Japan as a tropical storm. The following is a list of tropical cyclones that have reached 155 kts within the past ten years: 1995 - Angela (see note) 1997 - Keith 1998 - Zeb 2000 - Damrey 2001 - Faxai Since 1990, only four storms have been stronger than 155 kts. They are: STYs Ivan & Joan (1997), STY Paka (1997), and STY Gay (1992). Super Typhoons that have reached 150 kts include Mike (1990), Yuri (1991), and Maemi (2003). NOTE: There is strong reason to suspect that STY Angela was stronger than the current Best Track intensity of 155 kts. Dr. Karl Hoarau performed a detailed study of intense super typhoons of the post- reconnaissance era, and concluded that likely STY Gay of 1992 peaked at around 165 kts, and that Angela's peak was possibly near 170 kts. Karl's paper was presented at the AMS 26th Conference on Hurricanes and Tropical Meteorology at Miami in May, 2004. B. Storm Origins ---------------- At 0600 UTC on 11 June a new convective area developed and persisted within the monsoon trough approximately 340 nm east-southeast of Palau Island. It was added to JTWC's STWOs at this time, and the potential for development was given as poor. Animated multi-spectral imagery showed a possible LLCC with some deep convection. The suspect area was within a favourable environment of weak vertical wind shear and good diffluence. In the next regular STWO at 12/0600 UTC the potential was upped to fair. From there, the system proceeded to develop quickly, and a 12/2115 UTC SSM/I pass depicted spiraling rainbands curving into the centre. No TCFA was issued and JTWC released the first warning at 13/0000 UTC. C. Synoptic History ------------------- At the time of the initial warning Tropical Depression 09W was located 100 nm south-southwest of Yap and moving slowly west-northwestward at 3 kts. Because of the threat to Yap and Palau, the National Weather Service in Guam began writing special advisories at 13/0328 UTC. TC-09W remained at depression status until 13/1800 UTC when it was upgraded to Tropical Storm Dianmu, JMA having raised their MSW to 40 kts (10-min avg). Both enhanced infrared and water vapor imagery indicated increasing poleward outflow thanks to an upper-level LOW to the north- east, and forecasts indicated that this would be enhanced further as a shortwave trough approached from the northwest. By 14/0000 UTC JTWC had increased the MSW to 45 kts, and multi- spectral and QuikScat imagery both indicated that Tropical Storm Dianmu had consolidated to the southeast of the 13/1800 UTC warning position. Dianmu was essentially stationary approximately 100 nm west of Yap as it continued its strengthening phase, reaching typhoon intensity at 1800 UTC. At this time microwave imagery indicated that an eye could be forming, but this feature was not yet visible in infrared imagery. In addition to the poleward outflow, Dianmu had also acquired an excellent equatorward exhaust channel. The typhoon was centred just 85 nm north-northwest of Yap, the island lying within the zone of gale-force winds. Special advisories issued by the NWS mentioned that damaging winds were affecting Yap, but fortunately for the island community, Dianmu was beginning to move toward the north-northeast away from the island. The 15th of June was a day of very significant intensification for Dianmu. At 0000 UTC it was a 70-kt typhoon located 110 nm north- northwest of Yap. The eye feature was still evident in microwave imagery but not in multi-spectral. By 15/1200 UTC the eye had appeared in satellite imagery as the MSW reached 120 kts. Moving north to north- northwest at speeds ranging from 6 to 9 kts, Dianmu strengthened into a super typhoon with a MSW of 145 kts by the time of the 1800 UTC warning. Enhanced infrared imagery revealed a symmetrical eye measuring 15 nm across. In addition, the typhoon exhibited excellent outflow in both poleward and equatorward directions. At 16/0000 UTC Super Typhoon Dianmu, now with a MSW of 150 kts, was moving northward at 9 kts from a position approximately 300 nm north-northwest of Yap. The Prognostic Reasoning message issued at this time indicated that the northward heading would continue along the western periphery of the steering ridge located toward the northeast. The warning issued at 16/0000 UTC indicated the possibility of Dianmu strengthening to 160 kts in 12 hours. However, the peak intensity of Dianmu stopped 5 kts short of this value at 16/0600 UTC, the MSW remaining at 155 kts for the rest of the day. The wind radii were representative of an average-sized system and were as follows: winds of typhoon force extended 40 nm in all quadrants, the radius of 50-kt winds was 70 nm in all but the southeast quadrant (75 nm), and gale-force winds extended out 150 nm in the southeast quadrant and 140 nm elsewhere. (Super Typhoon Dianmu entered PAGASA's AOR on 16 June at about the time of its peak intensity, receiving the name Helen from that warning agency.) At 0000 UTC on 17 June Super Typhoon Dianmu/Helen was centered 675 nm southeast of Okinawa, moving northwestward at 9 kts. The MSW began to fall off and enhanced infrared imagery indicated that the eye temperature had cooled. By 1200 UTC the intensity of Dianmu was hovering at 130 kts as the storm took a jog towards the west-northwest for the next twelve hours. When Dianmu fell below super typhoon strength at 17/1800 UTC its eye was cloud-filled and poleward diffluence had weakened significantly. The next day Dianmu underwent a mini rejuvenation phase. This coincided with its northwestward passage over the slightly warmer Kuroshio Current. The typhoon was a 115-kt storm at 0000 UTC on 18 June approximately 520 nm south-southeast of Okinawa, and regained super typhoon intensity (MSW of 130 kts) at 18/1200 UTC. At this time, enhanced infrared and water vapor imagery showed a much improved poleward and equatorward diffluence pattern. Dianmu exhibited a 25-nm eye which began to warm. This indicated that the secondary peak had been reached and Dianmu was downgraded back to a 125-kt typhoon at 18/1800 UTC. At 0000 UTC on 19 June Typhoon Dianmu was centred 255 nm south- southeast of Okinawa and was beginning its turn toward the north. At this time, multi-spectral satellite imagery showed a ragged, cloud-filled eye with the majority of the deep convection occurring in the southern quadrants. A "lane" was also evident in infrared satellite imagery as a result of dry air entrainment in the northwest quadrant. Weakening commenced during the day with the MSW dropping below 100 kts at 19/1800 UTC. By 20/0000 UTC Typhoon Dianmu's radius of 50-kt winds were encroaching on Okinawa as the storm passed 75 nm to the east of the island. The weakening typhoon's outflow had diminished in all directions, deep convection had been eroded away in the western semi- circle, and the MSW had fallen to 80 kts. The system was beginning to interact with a trough located to the northwest of the system. Dianmu maintained typhoon-force winds until 20/1800 UTC when the intensity dropped below the typhoon threshold. At this time, the dying storm was located 175 nm south of Iwakuni, Japan. Now that Dianmu was entering the baroclinic zone, the storm began to accelerate and rapidly take on extratropical characteristics. It made landfall near the city of Muroto on the island of Shikoku in southern Japan early on the 21st, crossed the main island of Honshu, from there moving into Hokkaido before heading out into the North Pacific as an extratropical system. JTWC issued their final warning at 21/1800 UTC, locating the center approximately 80 nm northwest of Misawa, Japan. The final JMA bulletin referencing ex-Dianmu placed a weakening 35-kt gale center in the Sea of Okhotsk east of Sakhalin Island at 1200 UTC on 23 June. JMA's peak MSW (10-min avg) and minimum CP for Super Typhoon Dianmu/Helen were 100 kts and 915 mb, respectively. PAGASA's and NMCC's peak MSW estimates (10-min avg) were 105 kts and 130 kts, respectively. D. Meteorological Observations ------------------------------ The following observations were sent by Huang Chunliang--a special thanks to Chunliang for sending the data. (1) Rainfall ------------ (a) Falalop Island, Ulithi Atoll (WMO 91203, 10.0N/139.8E, 5 m) recorded 102.8 mm of rain from 12/0000 to 13/0000 UTC. (b) Koror, Palau (WMO 91408, 7.3N/134.5E, 30 m) recorded 121.7 mm from 13/0000-14/0000 UTC, and 115.6 mm from 13/0600-14/0600 UTC. (c) Owase, Japan (WMO 47663, 34.1N/136.2E, 27 m) measured a 24-hour accumulation of 207.5 mm from 21/0000 to 22/0000 UTC. (2) Sustained Wind Observations ------------------------------- Station Prefecture WMO ID Lat/Lon Alt Dir Kts UTC --------------------------------------------------------------------- Minamidaitojima Okinawa 47945 25.8N/131.2E 15 SE 43 19/1630 " " " " " SSE 50 19/1830 " " " " " SSE 56 19/2130 Kitakaitojima * " ----- -----/------ -- SSE 49 19/1630 " " ----- -----/------ -- SSE 51 19/1920 " " ----- -----/------ -- S 54 19/2140 Naha " 47936 26.2N/127.7E 28 N 32 19/1620 Naha " " " " NNW 37 19/1920 Naha " " " " NNW 39 19/2020 Nago " 47940 26.6N/128.0E 6 NNE 32 19/1620 Fukuoka Fukuoka 47807 33.6N/130.4E 3 N 21 21/0200 Sasebo Nagasaki 47812 33.2N/129.7E 4 N 25 20/1850 Oita Oita 47815 33.2N/131.6E 5 SSE 22 20/0430 Hagi Yamaguchi 47754 34.4N/131.4E 6 S 21 19/2230 Saga Saga 47813 33.3N/130.3E 6 NE 23 20/1130 Asosan Kumamoto 47821 32.9N/131.1E 1142 ENE 25 20/2230 Nagoya Aichi 47636 35.2N/137.0E 51 SSE 31 21/0620 Gifu Gifu 47632 35.4N/136.8E 13 SSE 33 21/0620 Tsu Mie 47651 34.7N/136.5E 3 SE 50 21/0320 Omaezaki Shizuoka 47655 34.6N/138.2E 45 S 30 21/0640 " " " " " SSW 31 21/0840 Tsuruga Fukui 47631 35.7N/136.1E 2 SE 32 21/0250 Kanazawa Ishikawa 47605 36.6N/136.7E 6 WSW 26 21/1040 Niigata Niigata 47604 37.9N/139.1E 2 ESE 26 21/0840 Shirakawa Fukushima 47597 37.1N/140.2E 355 S 28 21/1110 " " " " " SSW 33 21/1450 Akita Akita 47582 39.7N/140.1E 6 ESE 24 21/1210 Sakata Yamagata ----- 38.9N/139.9E 3 ESE 25 21/1050 " " ----- " " ESE 24 21/1210 Ishinomaki Miyazaki 47592 -----/------ 43 SE 37 21/1300 " " " -----/------ " SE 39 21/1340 Morioka Iwate 47584 39.7N/141.2E 155 S 24 21/1750 Hachinohe Aomori 47581 40.5N/141.5E 27 SE 27 21/1420 * - Kitadaitojima is the neighboring island northeast of Minamidaitojima (3) Wind Gust Observations -------------------------- Station Prefecture WMO ID Lat/Lon Alt Dir Kts UTC ---------------------------------------------------------------------- Minamidaitojima Okinawa 47945 25.8N/131.2E 15 SE 60 19/1009 " " " " " SE 71 19/1350 " " " " " SE 75 19/1542 " " " " " SSE 87 19/1750 " " " " " SSE 95 19/2120 Naha " 47936 26.2N/127.7E 28 N 53 19/1624 Naha " " " " N 59 19/1729 Naha " " " " NNW 61 19/2203 Nago " 47940 26.6N/128.0E 6 NNE 59 19/1550 Nago " " " " N 61 19/1959 Okinoerabu Kagoshima 47942 27.4N/128.7E 27 NE 57 19/1947 Naze Kagoshima 47909 28.4N/129.5E 3 N 61 20/0115 Shimizu Kochi 47898 32.7N/133.0E 31 E 70 20/1950 Murotomisaki Kochi 47899 33.3N/134.2E 185 ESE 78 20/1832 " " " " " ESE 100 20/2219 " " " " " SE 108 20/2240 " " " " " SE 111 unknown Fukuoka Fukuoka 47807 33.6N/130.4E 3 N 39 21/0156 Izuhara Nagasaki 47800 34.2N/129.3E 4 NW 44 21/0058 Oita Oita 47815 33.2N/131.6E 5 SE 36 20/0248 Hagi Yamaguchi 47754 34.4N/131.4E 6 S 41 20/0457 Saga Saga 47813 33.3N/130.3E 6 N 33 20/2234 Asosan Kumamoto 47821 32.9N/131.1E 1142 ENE 66 20/2217 Uwajima Ehime 47892 33.2N/132.6E 2 NNE 49 20/1600 Nagoya Aichi 47636 35.2N/137.0E 51 SSE 65 21/0619 Gifu Gifu 47632 35.4N/136.8E 13 SE 65 21/0548 Tsu Mie 47651 34.7N/136.5E 3 ESE 67 21/0314 Omaezaki Shizuoka 47655 34.6N/138.2E 45 S 52 21/0638 " " " " " S 54 21/0711 Tsuruga Fukui 47631 35.7N/136.1E 2 ESE 77 21/0248 Kanazawa Ishikawa 47605 36.6N/136.7E 6 SSW 29 21/0951 Niigata Niigata 47604 37.9N/139.1E 2 E 42 21/0839 Shirakawa Fukushima 47597 37.1N/140.2E 355 S 52 21/1236 " " " " " S 57 21/1456 Akita Akita 47582 39.7N/140.1E 6 ESE 45 21/1238 Sakata Yamagata ----- 38.9N/139.9E 3 ESE 42 21/1102 " " ----- " " ESE 45 21/1238 Ishinomaki Miyazaki 47592 -----/------ 43 SE 57 21/1257 Morioka Iwate 47584 39.7N/141.2E 155 S 39 21/1735 Hachinohe Aomori 47581 40.5N/141.5E 27 ESE 53 21/1419 E. Damage and Casualties ------------------------ At the time of this writing three people are known to have been killed with three persons reported missing as a result of Typhoon Dianmu's passage across Japan. Airline services and rail transport were disrupted, and the typhoon forced nine oil refineries to temporarily halt operations. Damage due to the storm appears to have been minimal. (Report written by Kevin Boyle with significant contributions by Huang Chunliang) TYPHOON MINDULLE (TC-10W / TY 0407 / IGME) 23 June - 5 July --------------------------------------------- Mindulle: contributed by North Korea, is the name of a flower, the dandelion A. Introduction --------------- As Super Typhoon Dianmu was spending the last of its energy over Japan, Typhoon Mindulle began forming north-northeast of Guam. Mindulle remained a tropical storm for several days as it passed through a high-shear environment before becoming a near super typhoon. The storm then weakened before veering north and crossing Taiwan where the poorly-defined LLCC led to significant differences in fixes between the different warning agencies. After striking Taiwan Mindulle moved toward Korea. B. Storm Origins ---------------- The area of deep convection that was to become Mindulle originated from the leading edge of a monsoon gyre and was first mentioned in JTWC's STWO issued at 0100 UTC on 21 June. At this time, multi- spectral imagery located a possible LLCC approximately 180 nm south of Guam. As the suspect area was located in a moderate vertical shear environment with weak diffluence aloft, the development potential was assessed as poor. Based on increasing organization, the potential for development was then upgraded to fair at 22/1300 UTC. A TCFA was issued at 23/0000 UTC for an area of convection that had persisted over the past 12 hours to the west of a fully-exposed LLCC and which was moving north-northwestward at 6 kts near 15.5N/144.8E. Based on the increasing organization of the storm, increasing deep convection and upper-level outflow, the STWO released at 23/0600 UTC indicated that JTWC would be issuing warnings on the system shortly. C. Synoptic History ------------------- The first warning was issued as promised at 0600 UTC on 23 June on Tropical Depression Mindulle (JMA had already named this system) which was moving west-northwestward at 8 kts with a MSW of 30 kts. The LLCC, located approximately 170 nm north-northwest of Guam, was partially- exposed to the east of the deep convection. At 23/1200 UTC Mindulle was upgraded to a tropical storm as it turned first northwestward, then back to the west-northwest and accelerated to around 11-13 kts. By 24/0000 UTC Mindulle was tracking westward as a 45-kt tropical storm approximately 335 nm west-northwest of Saipan, the LLCC still partially-exposed on the northeast side of the deep convection. This was to be the case for several days as the system moved west to west- southwestward through a high shear environment, as depicted in CIMSS Wind Shear Products, with upper-level winds reaching 50 to 60 kts in places. However, Mindulle fought on and reached an intensity of 55 kts at 24/1800 UTC. At 0000 UTC on 25 June Mindulle (named Igme by PAGASA when it entered their AOR) had weakened to 45 kts as the shearing began to take its toll. At this time the centre was fully-exposed again, being located approximately 810 nm east of Manila, Philippines. For some reason Mindulle suddenly slammed on the brakes, decelerating from 19 kts (at 24/1800 UTC) to only 4 kts, then accelerated back up to 11 kts six hours later. Shearing conditions began to relax and by 25/1200 UTC the centre was no longer exposed, at least temporarily. The MSW was brought back up to 50 kts at 25/1200 UTC as microwave imagery revealed that the LLCC had become partially-exposed again. The intensity of Mindulle held steady at 50 kts through much of the 26th (at 0000 UTC 26 June microwave imagery revealed that the LLCC had decoupled to the northeast of the deep convection and upper-level circulation) with a slight increase in intensity to 55 kts at 1800 UTC. At this time, microwave imagery suggested that a 70-nm eye could be forming. During the last two days, Mindulle's west to west-northwesterly movement took it to within 475 nm east-northeast of Manila at 0000 UTC on 27 June. At this time the cyclone began to track toward the northwest. Further intensification took place as a large eye appeared, and Mindulle was upgraded to a typhoon at 27/0600 UTC. The MSW was estimated to have reached 80 kts at 27/1800 UTC as the storm underwent a stair-stepping movement which continued into the next day. The MSW increased to 95 kts at 28/0000 UTC, and Mindulle reached its peak intensity of 125 kts at 28/1800 UTC (and this was maintained through the 29th). The typhoon was moving more slowly in a weaker steering environment between two HIGHs by this time with one HIGH building eastward across China while the other was retreating to the east of Okinawa. The result was a slow west to west-northwesterly movement for several days. At 0000 UTC on 30 June Typhoon Mindulle was still moving slowly west-northwestward, being located approximately 350 nm south of Taipei, Taiwan. A steady weakening trend had begun as the centre moved as close as 60 nm north of Luzon, Philippines. By 30/1200 UTC the MSW had fallen to 90 kts as the storm turned northwestward. At this time Mindulle exhibited a partially-exposed LLCC, as depicted in animated satellite imagery. At 30/1800 UTC Mindulle veered sharply to the north due to the formation of a TUTT-like feature to its northwest. Weakening continued into the next day as Mindulle, now on a definitive northward heading, began its approach to Taiwan. At 0000 UTC on 1 July Typhoon Mindulle's MSW was down to 75 kts and it was centred 180 nm south of Taipei, Taiwan. Most of the associated deep convection was located south of the LLCC. As the storm continued north- ward, its track bent to the northwest at 01/0600 UTC before resuming its northward course at 01/1200 UTC. At this time the system appeared to be consolidating but was downgraded to a 55-kt tropical storm after making landfall over Taiwan. Interaction with the mountains of Taiwan significantly weakened the storm further with winds soon down to 45 kts. The following day at 0600 UTC Mindulle was centred roughly over the northern end of Taiwan, but because of the difficulty in locating the LLCC there were differences of opinion in the actual position. Some agencies were apparently fixing the centre on the western side of Taiwan. JTWC considered this to be a circulation centre created by the leeside effect. The absence of QuikScat data, microwave imagery and the lack of synoptic observations failed to shed any light on the matter. Typhoon Mindulle failed to recover from its excursion across Taiwan. At 0000 UTC on 3 July the storm had weakened further to 35 kts and was moving north-northeastward at 9 kts approximately 150 nm north-northeast of Taipei. The 03/0600 UTC warning relocated the centre roughly 80 nm to the northwest of the previous position to 28.4N/121.7E, or 380 nm southwest of Cheju Do. The relocation was based on a combination of QuikScat, the Korean analysis, and the NCEP GFS initial panel which all indicated that Mindulle was actually located along the coast of China (see the following note from Huang Chunliang). The system continued to move north-northeastward as a fully-exposed system with very little deep convection and was downgraded to a tropical depression at 03/1800 UTC. What was left of Mindulle accelerated northeastward to 22 kts at 04/0000 UTC, then slowed to 14 kts as it headed toward Korea. The final warning was issued six hours later when the system was centred 90 nm southwest of Kunsan, Korea. JMA mentioned the ex-Mindulle system as a developing LOW and monitored it through the 5th, when it had weakened below gale force in the central Sea of Japan. JMA's and PAGASA's peak 10-min avg MSW estimates for Mindulle were 90 kts and 105 kts, respectively. The minimum CP estimated by JMA was 940 hPa. Huang Chunliang's Note--Landfall 1: According to the CWB warnings, Weak Typhoon 0407 (Mindulle) made landfall approximately 20 km south of Huanlien City, Taiwan around 01/1440 UTC with a MSW of 58 kts and a CP of 975 hPa. Landfall 2: According to the NMC warnings, Severe Tropical Storm 0407 (Mindulle) made landfall in Huanghua Town, Yueqing City (a sub-city of Wenzhou City), Zhejiang around 03/0130 UTC with a MSW of 49 kts and a CP of 985 hPa. D. Meteorological Observations ------------------------------ The following observations were sent by Huang Chunliang--a special thanks to Chunliang for sending the data. (1) Rainfall Observations from the Philippines ---------------------------------------------- (only amounts greater than 100 mm are listed) Station WMO ID Lat Lon Alt (m) Rain (mm) Time Period (UTC) ----------------------------------------------------------------------- Baguio 98223 16.4N 120.6E 1501 124.6 28/0000 - 29/0000 " " " " " 444.2 29/0000 - 30/0000 " " " " " 443.9 30/0000 - 01/0000 " " " " " 1012.7 28/0000 - 01/0000 Laoag 98223 18.2N 120.5E 5 289.6 29/0000 - 30/0000 " " " " " 288.8 30/0000 - 01/0000 Calayan 98133 19.3N 121.5E 13 161.2 29/0000 - 30/0000 Vigan 98222 17.6N 120.4E 33 136.0 30/0000 - 01/0000 Dagupan 98325 16.1N 120.3E 2 100.6 30/0000 - 01/0000 (2) Rainfall Observations from Taiwan - WMO Stations ---------------------------------------------------- (only amounts greater than 100 mm are listed) Station WMO ID Lat Lon Alt (m) Rain (mm) Time Period (UTC) ----------------------------------------------------------------------- Chenggong 46761 23.1N 121.4E 37 352.0 30/1600 - 01/1600 Hualien 46699 24.0N 121.6E 19 217.0 30/1600 - 01/1600 Taitung 46766 22.8N 121.2E 10 204.5 30/1600 - 01/1600 Lanyu 46762 22.0N 121.6E 325 139.0 30/1600 - 01/1600 Dawu 46754 22.4N 120.9E 8 128.0 30/1600 - 01/1600 Hengchun 46759 22.0N 120.8E 24 114.5 30/1600 - 01/1600 Mount Alisan 46753 23.5N 120.8E 2406 555.5 01/1600 - 02/1600 " " " " " 616.0 02/1600 - 03/1600 Dongshi 46730 23.3N 119.7E 45 405.0 01/1600 - 02/1600 Taichung 46753 24.2N 120.7E 78 308.5 02/1600 - 03/1600 (3) Rainfall Observations from Taiwan - CWB Stations ---------------------------------------------------- (a) For the Period: 29/1600 - 30/1600 UTC (only amounts >= 100 mm) ------------------------------------------------------------------- CWB Station ID County Rainfall ---------------------------------------------- C0R36 Pingtung 122.0 mm C1T95 Hualien 117.0 mm C1T97 " 113.0 mm C1T99 " 105.5 mm C0R42 Pingtung 103.5 mm (b) For the Period: 30/1600 - 01/1600 UTC (only amounts >= 200 mm) ------------------------------------------------------------------- CWB Station ID County Rainfall ---------------------------------------------- C0Z06 * Hualien 527.0 mm C1T99 " 299.0 mm C1T83 " 286.0 mm C1Z02 " 271.5 mm C1T94 " 262.0 mm C1T88 " 262.0 mm C0S83 Taitung 256.5 mm C1T98 Hualien 250.0 mm C1T90 " 243.0 mm C0T82 " 242.5 mm C1T97 " 237.5 mm C1T93 " 236.5 mm C0T9A " 234.5 mm C1T86 " 234.5 mm C0T87 " 233.5 mm C0S74 Taitung 228.5 mm C1Z03 Hualien 228.0 mm C0T9F " 226.0 mm C1T95 " 222.0 mm C1Z01 " 221.0 mm C1T81 " 221.0 mm C0Z05 " 217.5 mm C0T96 " 215.0 mm C1T89 " 208.5 mm C0T9E " 208.0 mm C0T9G " 206.0 mm C0S81 Taitung 205.5 mm C1Z04 Hualien 202.0 mm A0T78 " 201.5 mm C1T92 " 201.0 mm * - C0Z06 = Station Yuli (c) For the Period: 01/1600 - 02/1600 UTC (only amounts >= 400 mm) ------------------------------------------------------------------- CWB Station ID County Rainfall ---------------------------------------------- C0R10 * Pingtung 730.5 mm C1V30 Kaohsiung 666.5 mm C1V24 " 583.5 mm C1R14 Pingtung 580.0 mm C1V19 Kaohsiung 577.5 mm C1R12 Pingtung 544.5 mm C1V27 Kaohsiung 528.0 mm C1M61 Chia-I 527.0 mm C1V22 Kaohsiung 518.5 mm C0M53 Chia-I 504.0 mm C1M39 " 503.5 mm C0M41 " 502.0 mm C1F88 Nantou 480.0 mm C1V23 Kaohsiung 466.5 mm C0O81 Tainan 459.6 mm C1F94 Taichung 454.5 mm C1M60 Chia-I 438.5 mm C1M54 " 436.5 mm C1V34 Kaohsiung 432.5 mm C0X02 Tainan 429.5 mm C1M44 Chia-I 428.0 mm C1O87 Tainan 425.0 mm C1V21 Kaohsiung 409.0 mm C1V20 " 403.5 mm C1R13 Pingtung 401.5 mm C0R15 " 400.0 mm * - C0R10 = Station Mount Weiliaosan (d) For the Period: 02/1600 - 03/1600 UTC (only amounts >= 400 mm) ------------------------------------------------------------------- CWB Station ID County Rainfall ---------------------------------------------- C1V19 Kaohsiung 670.0 mm C1F88 Nantou 647.0 mm C1V22 Kaohsiung 636.5 mm C1V30 " 616.5 mm C1V27 " 605.0 mm C1F89 Taichung 603.5 mm C1F94 " 569.5 mm C1H85 Nantou 554.5 mm C0F95 " 540.5 mm C1V46 Kaohsiung 538.0 mm C1F87 Taichung 516.0 mm C1V20 Kaohsiung 508.5 mm C0H9A Nantou 501.5 mm C1V24 Kaohsiung 460.0 mm C0R10 Pingtung 454.0 mm C1F9D Taichung 440.0 mm C1V29 Kaohsiung 440.0 mm C0M53 Chia-I 437.5 mm C1F9H Taichung 432.0 mm C1R14 Pingtung 429.5 mm C1M63 Chia-I 424.0 mm C1M62 " 423.0 mm C1H86 Nantou 417.0 mm C1F9E Taichung 415.0 mm C1F91 " 413.5 mm (4) Rainfall Observations from the Chinese Mainland --------------------------------------------------- (only amounts greater than 50 mm are listed) All the following are for the period: 02/0000 - 03/0000 UTC. Station Province WMO ID Lat Lon Alt (m) Rain (mm) ------------------------------------------------------------------- Ruian Zhejiang ----- 27.8N 120.7E 38 68.9 Pingtan * Fujian 58944 25.5N 119.8E 31 56.0 Dachen Dao Zhejiang 58666 28.5N 121.9E 84 51.1 Fuding Fujian 58754 27.3N 120.2E 38 50.0 Yuhuan Zhejiang ----- ----- ------ -- 78.0 Dongtou Zhejiang ----- ----- ------ -- 57.0 * - Pingtan is one of the counties of Fuzhou. (5) Wind Observations --------------------- Station Yonagunijima, Okinawa Prefecture, WMO 47912, 24.5N/123.0E, Alt 30 m, recorded a peak gust of S 63 kts (time unknown). A gust of SE 62 kts was recorded at 01/1430 UTC. Station Ishigakijima, Okinawa Prefecture, WMO 47918, 24.3N/124.2E, Alt 6 m, recorded a peak gust of S 54 kts (time unknown). Gusts of S 52 kts and SE 46 kts were recorded at 02/0540 and 01/1704 UTC, respectively. E. Phil Smith's Encounter with Mindulle --------------------------------------- The following account was sent by Phil Smith, a transplanted Aussie living in Hong Kong. A special thanks to Phil for sharing his personal "reconnaissance" of Typhoon Mindulle. "This afternoon I took off from Taipei right in the midst of Mindulle's closest approach. Even while pushing back from the gate, the plane was rocking everywhere and violent squalls of rain were belting the portside windows of the plane so hard you expected the windows to come in. Taxiing out to the runway, the plane also was being shaken violently by the powerful gusts of winds. The take-off run seemed relatively smooth, but as soon as we began to climb we all enjoyed a Disneyland roller coaster ride with the plane sometimes plummeting earthwards, sometimes suddenly rocketing heavenwards, and generally copping quite a buffeting. Suddenly, a short distance into the climb, the sun shone brightly, the sky was bright, clear, blue, and the ride became very smooth, except for what felt like one colossal downdraft. "The captain came on the public address system and ordered all cabin crew and passengers to remain seated and with belts fastened and ordered that there was no time to even go to the toilet. He said, 'We are now passing through the eye of the typhoon and there will be a great deal more strong turbulence in just a few more seconds.' Seconds later we plunged again into deep dark grey cloud and enjoyed another roller coaster ride as before. We soon rose above the lower mass of clouds, although there were still higher clouds far above us with a few breaks of blue sky. We were right up to cruising altitude before the 'Fasten Seat Belts' sign was cancelled and the crew were allowed to begin their in-flight service. "Technically, at the time we flew through the eye, the storm had been downgraded to a tropical storm, and a short distance below the plane the eye was filled with clouds. However, I still unexpectedly enjoyed the dream of a lifetime: seeing the eye of a storm from the air, from the inside, with my own eyes. What a thrill it was! I have experienced two previous eye-passages with my feet planted firmly on the ground, but to be flying through the middle and seeing the majesty of the encircling clouds towering above the plane and glistening in the unbelievably bright sunlight was a truly unforgettable experience." F. Damage and Casualties ------------------------ News reports indicate that Mindulle/Igme was responsible for 31 deaths in the Philippines and for $9.8 million worth of damage to crops and infrastructure in the Cagayan Valley region. Eleven persons were still missing at the time of this writing. The NDCC indicated that a total of 113,004 families, or 577,471 persons, had been displaced by the typhoon. Total damage to crops and infrastructure was estimated at P1.1 billion. Agricultural crops worth P654.2 million were destroyed while damage to infrastructure was placed at P444.8 million. In Taiwan, torrential rains associated with Typhoon Mindulle caused floods and mudslides which claimed the lives of at least 25 people. Twelve persons were reported missing and damages were equivalent to about 400 million US dollars. Flooding knocked out electricity to as many as 213,000 homes. An official at the Taiwan Power Company estimated damage and lost revenue at about T$10 billion (US$297 million). The island's main hydroelectric power project was hardest hit, with two plants along the Tachiah River buried by mudslides and two others forced to shut down after rivers rose. To add insult to injury, Taiwan was rocked by an earthquake measuring 5.8 on the Richter scale just a few days after the passage of Mindulle while the island was coping with the aftermath of the flooding. Additional articles of interest can be found at the following URL: http://www.reliefweb.int/w/rwb.nsf/vLND> (Report written by Kevin Boyle with significant contributions by Huang Chunliang.) TYPHOON TINGTING (TC-11W / TY 0408) 25 June - 6 July -------------------------------------- Tingting: contributed by Hong Kong, is a fairly common pet name for young girls A. Storm Origins ---------------- Typhoon Tingting was the culmination of a very active June in the Northwest Pacific basin with five typhoons forming during the month. An area of convection formed and persisted about 600 nm east-southeast of Guam on 24 June. Animated multi-spectral imagery revealed a weak LLCC beneath an area of persistent convection, and an upper-level analysis revealed moderate vertical shear and weak diffluence. By 0000 UTC on 25 June the disturbance had moved westward to a position about 515 nm east-southeast of Guam. Satellite imagery indicated that deep convection was consolidating around the LLCC, and an upper-level analysis showed decreased vertical shear and favorable diffluence. A TCFA was issued for the system at this time by JTWC. At 0600 UTC JMA began classifying the system as a 30-kt tropical depression in their High Seas bulletins. B. Synoptic History ------------------- The first JTWC warning on Tropical Depression 11W was issued at 1200 UTC on 25 June. The center was located about 450 nm east-southeast of Guam, moving westward at 5 kts, and the MSW was estimated at 30 kts. TD-11W was forecast to track northwestward along the western periphery of a mid-level ridge to the northeast. At 26/0000 UTC the system was located almost 400 nm east-southeast of Guam--at this juncture JMA upgraded the depression to tropical storm status and assigned the name Tingting. Six hours later JTWC upgraded Tingting to a tropical storm. By 1200 UTC Tingting was tracking slowly northwestward as forecast, and by 1800 UTC had reached a position about 300 nm east of Guam. Tingting slowly intensified on the 27th as it neared the Mariana Islands. At 1200 UTC the center was located approximately 115 nm east-southeast of Saipan with the MSW estimated at 55 kts. A 27/1123 UTC SSM/I pass in the 37-GHz band suggested that a ragged eye was beginning to form. Tingting's northwesterly motion was forecast to continue as the system tracked along the southwest quadrant of the steering ridge to the north. This ridge was moving to the east and was expected to build in the equatorward direction to the east of the tropical cyclone, thereby causing Tingting to begin moving more poleward. At 0000 UTC on 28 June satellite CI estimates ranged from 55-77 kts. Since an eye appeared to be forming, JTWC upgraded Tingting to a 65-kt minimal typhoon. Six hours later the MSW had increased to 75 kts as Tingting's center was passing through the central Marianas about 95 nm north of Saipan, or near the tiny island of Sarigan. The storm's organization improved through the day, and at 1800 UTC the MSW had reached 80 kts. (JMA upgraded Tingting to a typhoon at this time.) The 80-kt intensity represents Tingting's peak per JTWC analysis, and was maintained for 18 hours. Early on the 29th the typhoon made a little bit of a west-northwestward jog, but by 1800 UTC the anticipated northward turn had occurred with Tingting moving north at 13 kts from a position approximately 160 nm south-southeast of Iwo Jima. At its peak intensity gales covered an area over 300 nm in diameter with the radius of typhoon-force winds estimated at 40-45 nm. The last day of June saw Typhoon Tingting continue its journey northward, passing only about 50 nm east of Iwo Jima during the day. By 30/1800 UTC the center of the cyclone was located about 175 nm north-northeast of the island. JTWC brought the intensity down during the 30th to 65 kts by 1800 UTC, but surprisingly JMA's peak 10-min avg MSW of 85 kts occurred at 1200 UTC. (More discussion on this below.) Tingting continued to weaken on 1 July as cooler, drier air was entrained into the system from the northwest. JTWC downgraded the system to a 55-kt tropical storm at 1200 UTC, but JMA maintained Tingting as a typhoon for another 24 hours. (Intensity estimates from at least one satellite fix agency remained at 65 kts through 02/0600 UTC.) At 01/1800 UTC the storm was located approximately 410 nm southeast of Tokyo and moving east-northeastward at 12 kts. On 2 July Tropical Storm Tingting continued to move slowly northeastward, reaching a point about 430 nm east-southeast of Tokyo by 1800 UTC. By this time JMA had downgraded the system to tropical storm status. The storm's forward motion accelerated significantly on the 3rd as it got caught up in mid-latitude westerlies. By 03/1800 UTC Tingting was located about 770 nm east of Tokyo and speeding east-northeastward at 19 kts. More cold, dry air had become entrained into the system and convection had significantly decreased. The 1800 UTC warning was the final one from JTWC and declared Tingting to be an extratropical LOW with 45-kt winds. JMA issued tropical cyclone warnings for one more cycle, then declared Tingting extratropical at 04/0600 UTC. The remnants of Tingting continued northeastward, gradually slowing and turning north. The final reference to the system in JMA's High Seas bulletins was at 1800 UTC on 6 July and placed the weakening 35-kt gale just southeast of the Kamchatka Peninsula. C. Meteorological Observations ------------------------------ Typhoon Tingting brought prodigious amounts of rainfall to Guam as the center passed through the Mariana Islands to the north. Following is part of an e-mail from Mark Lander which describes in vivid detail the conditions on Guam (e-mail dated 27 June 2004): "We sure are in the thick of this one. My rain gauges just topped 11 inches (280 mm), with most of it falling in the past 8 hours. Winds are WNW 30 kts with gusts 40-45 kts. The sea is boiling with white caps, and is thick with red mud plumes extending far offshore in many places. There is a possibility for another 10 inches of rain in the next 24-36 hours, giving us a storm total of over 20 inches (over 500 mm)! Even before this tropical storm, we were at about 16 inches of rain for the month which was the wettest June in 47 years of record keeping. "All of this rain has come from outer rainbands, and not from the TC core which is just now coming into NEXRAD range at 240 nm. Tingting is expected to pass near Saipan tomorrow morning (about 12 hours from now), and therefore the CPA will be about 170 nm to the NE of Guam. More rain is now beginning to pound against my door. Driving today has been amazing! The roads are covered in "lakes", and assorted rivers and "waterfalls" exist everywhere. Fortunately, much of Guam is limestone (island Karst), and most of the water rapidly infiltrates. Only in the south are there exposed volcanics with surface streams (some really great waterfalls under normal circumstances--I'd love to see those streams today!)." In a more recent e-mail Mark stated that some stations in Guam received more than 600 mm in a 24-hour period, and that peak wind gusts on the island were around 50 kts. Huang Chunliang sent one rainfall observation from Guam. The NWSO at Agana (WMO 91212, 13.5N/144.8E, Alt 75 m) recorded a 24-hour total of 145.3 mm from 27/1200 to 28/1200 UTC. Chunliang also sent a wind gust observation from Chichijima (WMO 47971, 27.1N/142.2E, Alt 3 m). The station recorded a peak gust of 79 kts at 30/1030 UTC. (Thanks to Chunliang for the tidbits of data and to Mark for sharing his account of conditions on Guam.) NOTE: More observations are included in Section E below. D. Damage and Casualties ------------------------ The author has received no reports of damage or casualties resulting from Typhoon Tingting. E. Further Discussion --------------------- JTWC's peak estimated 1-min avg MSW for Tingting was 80 kts, from 1800 UTC on 28 June through 1200 UTC on the 29th. During the time of JTWC's peak intensity, JMA's estimated 10-min avg MSW was in the 65-70 kt range. By 1200 UTC on 30 June, JTWC's intensity had decreased to 70 kts while JMA's MSW had increased to 85 kts, or roughly equivalent to a 1-min avg MSW of 95 kts. As students of Northwest Pacific tropical cyclones know, for systems of typhoon intensity or greater it is very unusual for JMA's MSW to exceed JTWC's estimated intensity, especially by as much as 25 kts (when converted to equivalent 1-min avg values). I asked Dr. Karl Hoarau of Cergy-Pontoise University near Paris to perform an analysis of Tingting's intensity during this period. His reply follows (slightly edited): "First, I'll give you some data recorded by the stations. On 28 June at 1600 UTC, Pagan recorded a gust of 113 kts. This normally matches with a MSW over 1 minute of 92 kts. At that time, the hourly AODT developed by CIMSS gave 102 kts (5.5) while JTWC had the MSW at 80 kts at 1800 UTC. On 30 June at 0300 UTC, Iwo Jima recorded a SLP of 969 hPa with a MSW of 48 kts over 10 minutes (54 kts over 1 minute) and a gust of 68 kts when TY Tingting was 54 nm east of the island. This was the basis for JMA to give an intensity of 950 hPa/80 kts (90 kts over 1 minute or T5.0). At 30/0000 UTC, the MSLP was at 979 hPa on the island. At that time, JMA still gave an intensity of 965 hPa/70 kts (80 kts over 1 minute or T4.5+). "The question is--was TY Tingting intensifying during that time? The response is definitely not. The AODT was 4.5 and manual Dvorak T-numbers that I computed were at 4.5 too from 29 June at 1800 UTC until 30 June at 1013 UTC when they decreased to 4.0! But obviously, the Current Intensity (CI) was above the T-numbers since the intensity was decreasing. "At 30/1030 UTC Chichijima recorded a SLP of 971 hPa and a maximum gust of 79 kts, which matches with a MSW of 65 kts. These winds were recorded in the north-northwest part of the eyewall, which had breaks in the convection. In the eastern eyewall where the convection was more active, the winds were probably stronger. At 1500 UTC, Chichijima recorded a SLP of 959.4 hPa with light winds (12 kts) and 0.5 mm of rain in one hour when the center of the big eye of Tingting was located 20 nm east of the island. At 0600 UTC JMA still upped the intensity to 950 hPa/80 kts (90 kts over 1 minute), and at 1200 UTC further increased the intensity to 945 hPa/85 kts (95 kts over 1 minute), which means T5.5 in their Dvorak classification. From 1200 to 1500 UTC the intensity of Tingting was decreasing from 4.0 to 3.5, and at 1500 UTC the eye temp- erature was around +4 C, and the closed ring of convection was "Off White" (+9 C to -30 C). From 1200 to 1500 UTC, CIMSS gave a current intensity of 75 kts. "In summary, it is possible that TY Tingting reached a peak intensity of 90-100 kts on 28 June around 1800 UTC. And then it gradually weakened. But the CI-numbers are stronger than the T-numbers in the Dvorak technique. On the 30th at 1200 UTC I do agree with CIMSS for a CI of 75-80 kts. As TY Tingting had a rather big low-level circulation, it is possible that the SLP was lower than the normal pressure (Atkinson and Holliday) for a given MSW. "The intensification given by JMA on 30 June was based on the SLP recorded in the two stations I mentioned, but not on the satellite pictures. Moreover, at 1500 UTC, I think that the minimum SLP in the eye of the typhoon was not much lower than the 959.4 hPa recorded at Chichijima." (A special thanks to Karl sending his analysis of Typhoon Tingting.) (Report written by Gary Padgett with significant contributions by Mark Lander and Karl Hoarau.) ************************************************************************* NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for June: 2 tropical depressions ** ** - Not classified as depressions by JTWC North Indian Ocean Tropical Activity for June --------------------------------------------- No systems were classified as tropical depressions or storms in the Bay of Bengal or Arabian Sea by JTWC during June, but two systems were treated as deep depressions (MSW >= 30 kts) by the Indian Meteorological Department. The temporary NRL invest numbers for these systems were 91A and 92B. Depression 91A occurred in the eastern Arabian Sea during the second week of June, and JTWC did issue two TCFAs for this system on the 11th and 12th, but the formation alert was cancelled on the 13th as the system weakened. One very knowledgeable and experienced meteor- ologist (who normally wishes to remain anonymous) opined that the Arabian Sea system likely had winds to 50 kts at one point. The Bay of Bengal system, Depression 92B, made landfall on 13 June approximately 240 nm southwest of Calcutta. This system remained fairly well-organized as an overland depression for nearly 48 hours following landfall. In one of their general tropical weather summaries for the Southeast Asia region, NMCC referred to this system as a tropical storm. Huang Chunliang has sent me a listing of some rainfall observations made in association with this depression. These are listed below: Station State Rain (cm) Date/Time (UTC) ------------------------------------------------------------------ Bhagamandala KARNATAKA 12 cm [11/03-12/03Z] Port Blair ANDAMAN & NICOBAR ISLANDS 11 cm [11/03-12/03Z] Kottigehara KARNATAKA 11 cm [11/03-12/03Z] Valparai TAMIL NADU & PONDICHERRY 10 cm [11/03-12/03Z] Valparai TAMIL NADU & PONDICHERRY 19 cm [12/03-13/03Z] Digha WEST BENGAL 16 cm [12/03-13/03Z] Paderu ANDHRA PRADESH 16 cm [12/03-13/03Z] Tekkali ANDHRA PRADESH 13 cm [12/03-13/03Z] Kalingapatnam ANDHRA PRADESH 11 cm [12/03-13/03Z] Titlagarh ORISSA 31 cm [13/03-14/03Z] Balimundali ORISSA 18 cm [13/03-14/03Z] Valparai TAMIL NADU & PONDICHERRY 17 cm [13/03-14/03Z] Kalaikunda WEST BENGAL 13 cm [13/03-14/03Z] Jagdalpur CHHATTISGARH 12 cm [13/03-14/03Z] Bhagamandla KARNATAKA 11 cm [13/03-14/03Z] Medikeri KARNATAKA 10 cm [13/03-14/03Z] Durg CHHATTISGARH 34 cm [14/03-15/03Z] Dongargarh CHHATTISGARH 18 cm [14/03-15/03Z] Raipur CHHATTISGARH 16 cm [14/03-15/03Z] Mana CHHATTISGARH 16 cm [14/03-15/03Z] Bemetara CHHATTISGARH 15 cm [14/03-15/03Z] Dongargaon CHHATTISGARH 14 cm [14/03-15/03Z] Gandai CHHATTISGARH 14 cm [14/03-15/03Z] Saraipalli CHHATTISGARH 12 cm [14/03-15/03Z] Rajnandgaon CHHATTISGARH 11 cm [14/03-15/03Z] Messanjore JHARKHAND 10 cm [14/03-15/03Z] Maither MADHYA PRADESH 22 cm [15/03-16/03Z] Satna MADHYA PRADESH 12 cm [15/03-16/03Z] Nagodre MADHYA PRADESH 10 cm [15/03-16/03Z] Langi MADHYA PRADESH 10 cm [15/03-16/03Z] Pendra CHHATTISGARH 13 cm [15/03-16/03Z] Gorakhpur UTTAR PRADESH 13 cm [16/03-17/03Z] Bansi UTTAR PRADESH 12 cm [16/03-17/03Z] Birdghat UTTAR PRADESH 11 cm [16/03-17/03Z] Kakrahi UTTAR PRADESH 11 cm [16/03-17/03Z] Turtipar UTTAR PRADESH 10 cm [16/03-17/03Z] Khajuraho MADHYA PRADESH 13 cm [16/03-17/03Z] Dehradun UTTARANCHAL 12 cm [17/03-18/03Z] ************************************************************************* SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E Activity for June: No tropical cyclones ************************************************************************* NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E Activity for June: No tropical cyclones ************************************************************************* NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E Activity for June: No tropical cyclones ************************************************************************* SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E Activity for June: 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, 1998 summary. I don't normally include the Glossary in most months in order to help keep them from being too long. If anyone would like to receive a copy of the Glossary, please e-mail me and I'll be happy to send them a copy. ************************************************************************* 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 from the archive sites listed below. (Note: I do have a limited e-mail distribution list for the track files. If anyone wishes to receive these via e-mail, please send me a message.) 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. Back issues can be obtained from the following websites (courtesy of Michael Bath, Michael V. Padua, Michael Pitt, and Chris Landsea): http://australiasevereweather.com/cyclones/> http://www.typhoon2000.ph> http://mpittweather.com> ftp:// ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/> 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: http://www.met-office.gov.uk/sec2/sec2cyclone/sec2cyclone.html> TROPICAL CYCLONE REPORTS AVAILABLE JTWC now has available on its website the complete Annual Tropical Cyclone Report (ATCR) for 2002 (2001-2002 season for the Southern Hemisphere). ATCRs for earlier years are available also. The report for the 2002-2003 Southern Hemisphere season has also recently been added. The URL is: http://199.10.200.33/jtwc.html> Also, TPC/NHC has available on its webpage nice "technicolor" tracking charts for the 2003 Atlantic and Eastern North Pacific tropical cyclones; also, storm reports for all the 2003 Atlantic and Eastern North Pacific cyclones are now available, as well as track charts and reports on storms from earlier years. The URL is: http://www.nhc.noaa.gov> A special thanks to Michael Bath of McLeans Ridges, New South Wales, Australia, for assisting me with proofreading the summaries. PREPARED BY Gary Padgett E-mail: [email protected] Phone: 334-222-5327 Kevin Boyle (Eastern Atlantic, Western Northwest Pacific, South China Sea) E-mail: [email protected] Huang Chunliang (Assistance with Western Northwest Pacific, South China Sea) E-mail: [email protected] Simon Clarke (Northeast Australia/Coral Sea, South Pacific) E-mail: [email protected] ************************************************************************* *************************************************************************
Document: summ0406.htm
Updated: 26th October 2006 |
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