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Monthly Global Tropical Cyclone Summary January 2004 [Summaries and Track Data] [Prepared by Gary Padgett] |
MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY JANUARY, 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.) ************************************************************************* JANUARY HIGHLIGHTS --> Southwest Indian tropical storm crosses Madagascar three times --> Very intense South Pacific cyclone devastates Niue --> Extremely rare South Atlantic tropical cyclone affects Brazil ************************************************************************* ***** Feature of the Month for January ***** TROPICAL CYCLONE NAMES for the NORTHWEST PACIFIC BASIN Beginning in 2000 tropical storms and typhoons forming in the North Pacific west of the Dateline are assigned names by JMA taken from a new list of Asian names contributed by fourteen nations and territories from the western Pacific and eastern Asia. Names are not allocated in alphabetical order and the majority are not personal names--instead names of animals, plants, fictional characters, descriptive adjectives, places--even foods--are utilized. The entire list consists of 140 names and all names will be used before any are repeated. The last name assigned in 2003 was Lupit in late November while one tropical cyclone, Sudal, has already been named in 2004. The next 36 names on the list are (** indicates name has already been assigned in 2004): Sudal ** Namtheun Sarika Talas Nida Malou Haima Noru Omais Meranti Meari Kulap Conson Rananim Ma-on Roke Chanthu Malakas Tokage Sonca Dianmu Megi Nock-ten Nesat Mindulle Chaba Muifa Haitang Tingting Aere Merbok Nalgae Kompasu Songda Nanmadol Banyan Since 1963 PAGASA has independently named tropical cyclones forming in the Philippines' AOR--from 115E to 135E and from 5N to 25N (except for a portion of the northwestern corner of the above region). Even though the Philippines contributed ten names to the international list of typhoon names, PAGASA still continues to assign their own names for local use within the Philippines. It is felt that familiar names are more easily remembered in the rural areas and that having a PAGASA- assigned name helps to underscore the fact that the cyclone is within PAGASA's AOR and potentially a threat to the Philippines. Another consideration may be PAGASA's desire to assign a name when a system is first classified as a tropical depression. Since tropical and/or monsoon depressions can bring very heavy rainfall to the nation which often results in disastrous flooding, the weather service feels that assigning a name helps to enhance public attention given to a system. Beginning with 2001 PAGASA began using new sets of cyclone names. These do not all end in "ng" as did the older names. Four sets of 25 names will be rotated annually; thus, the set for 2004 will be re-used in 2008. In case more than 25 systems are named in one season, an auxiliary set will be used. PAGASA names for 2004 are (** indicates name has already been assigned in 2004): Ambo ** Julian Rolly Butchoy ** Karen Siony Cosme Lawin Tonyo Dindo Marce Unding Enteng Nina Violeta Frank Ofel Winnie Gener Pablo Yoyong Helen Quinta Zosimo Igme In the unlikely event that the list is exhausted, the following names would be allocated as needed: Alakdan, Baldo, Clara, Dencio, Estong, Felipe, Gardo, Heling, Ismael, Julio. **** Index to Feature of the Month Articles for 2003 **** Jan - TROPICAL CYCLONE NAMES for the NORTHWEST PACIFIC BASIN (also Index to Feature of the Month Articles for 2002) Feb - SOUTHERN HEMISPHERE TROPICAL CYCLONE STATISTICS Mar - UPDATED TABLES OF ATLANTIC NET TROPICAL ACTIVITY also GLOSSARY of ABBREVIATIONS and ACRONYMS Apr - WESTERN HEMISPHERE TROPICAL CYCLONE NAMES for 2003 May - UPDATED NORTHEAST PACIFIC STATISTICS Jun - NORTH INDIAN OCEAN TROPICAL CYCLONE STATISTICS Jul - FORECASTING AUGUST ATLANTIC TROPICAL CYCLONE ACTIVITY Aug - INDIVIDUAL MONTHLY FORECASTS FOR SEPTEMBER AND OCTOBER Sep - SOUTHERN HEMISPHERE TROPICAL CYCLONE NAMES 2003-2004 SEASON Oct - INTENSE VERY LATE-SEASON CARIBBEAN HURRICANES Nov - TROPICAL CYCLONE CLIMATOLOGICAL DATA for the SOUTHERN HEMISPHERE and SOUTH INDIAN OCEAN Dec - TROPICAL CYCLONE CLIMATOLOGICAL DATA for the SOUTH PACIFIC OCEAN ************************************************************************* ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for January: No tropical cyclones ************************************************************************* SOUTH ATLANTIC (SAT) - Atlantic Ocean South of the Equator Activity for January: 1 tropical depression or tropical storm TROPICAL CYCLONE 18 - 21 January ------------------------------------ During a rather pronounced mid-January lull in tropical cyclone activity across the Southern Hemisphere, a surprise popped up off the coast of Brazil. A system which in satellite imagery appeared to be either a strong tropical depression or weak tropical storm formed to the southeast of Salvador, Brazil. On the morning of 20 January Mark Lander alerted the tropical cyclone community to the presence of a small system off the Brazilian coast which appeared to be a tropical cyclone. The small system was located along a trough which extended southeastward from a large monsoon-like low pressure area over tropical South America. This system is only the second known tropical cyclone to be sighted over the South Atlantic since the advent of meteorological satellites in the late 1960s. The first was a system off the coast of Angola in April, 1991, which was either a strong tropical depression or else a minimal tropical storm. According to Roger Edson, the system began to take shape on the 17th along an old trough-axis boundary. The system appeared to have reached its peak of development on 19 January when it exhibited a small, transient CDO and well-defined curved bands along its western side. According to Tony Cristaldi, around 1115 UTC the cyclone was centered near 15S, 37W, or approximately 150 nm southeast of Salvador. By late on the 19th it was undergoing strong southerly shear; however, a tightly- wound low-level vortex was visible in satellite imagery. The LOW weakened as it moved westward and inland along the coast of Brazil. Needless to say, there were very few synoptic observations from the region of the cyclone. Derrick Herndon relates that the AMSU pressure estimation algorithm indicated a minimum MSLP of 1003 mb around 0900 UTC on 19 January. QuikScat data indicated peak winds of around 30 kts late on the 19th. Ship C6I09 reported a pressure of 1007.7 mb and southerly winds of 25 kts at 19/1800 UTC while located 50 nm west of the center. The same ship reported 1009.6 mb and northwest winds of 30 kts six hours later while situated northeast of the center. These ship observations suggest that the system could have been a minimal tropical storm, but the peak intensity of the cyclone is a matter of conjecture. A few days after the system had moved inland, Kevin Boyle sent me a snippet of news he'd located on the BBC Weather Site: "Intensely heavy rain has continued to deluge much of Brazil, in particular the northeastern corridor. This has led to massive flooding, destroying not only crops but also people's homes. A state of emergency has been declared in Aracaju after hundreds of homes were washed away. "In Alagoas, the river overflowed and burst its banks, flooding further homes, destroying bridges and causing parts of the highway to collapse. But with heavy rain forecast to last until the end of January, the end is not yet in sight. According to past records, it has already rained more this month so far than at any time in the last 39 years." With a large monsoon LOW covering much of Brazil, it seems likely that the aforementioned rainfall was not completely attributable to the tropical cyclone, but it could have certainly been an enhancing factor. No official name was applied to this system. Kevin Boyle unofficially dubbed it Tropical Cyclone "Samba" in honor of a popular type of Brazilian music, so that name got used in e-mail messages discussing the system. But because the name was not officially assigned by any warning agency, I have refrained from referring to it as "Samba" in this report. A special thanks to all the persons named in the above report who contributed bits and pieces of information regarding this very interesting weather system. (Report written by Gary Padgett) ************************************************************************* NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180 Activity for January: No tropical cyclones ************************************************************************* NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180 Activity for January: No tropical cyclones ************************************************************************* NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for January: No tropical cyclones ************************************************************************* SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E Activity for January: 1 severe tropical storm 1 intense tropical cyclone Sources of Information ---------------------- The primary sources of tracking and intensity information for Southwest Indian Ocean tropical cyclones are the warnings issued by the Tropical Cyclone Warning Centre on La Reunion Island, part of Meteo France (MFR), and the Regional Specialised Meteorological Centre for the basin. However, tropical cyclones in this region are named by the sub-regional warning centres on Mauritius and Madagascar with longitude 55E being the demarcation line between their respective areas of warning responsibility. The La Reunion centre only advises these agencies regarding the intensity of tropical systems. References to sustained winds imply a 10-minute averaging period unless otherwise stated. In the companion tropical cyclone tracks file, I occasionally annotate positions from warnings issued by the Joint Typhoon Warning Center (JTWC) of the U. S. Air Force and Navy, located at Pearl Harbor, Hawaii, when they differ from MFR's coordinates by usually 40-50 nm or more. The JTWC warnings are also the source of the 1-minute average maximum sustained wind values included in the tracks file. Additionally, information describing details of satellite imagery and atmospheric circulation features included in the narratives is often gleaned from the JTWC warnings. Southwest Indian Ocean Tropical Activity for January ---------------------------------------------------- As the month of January opened Severe Tropical Storm Darius was approaching Mauritius. The storm passed very close to the east side of the island on the 2nd, then scurried away into higher latitudes and became extratropical on the 4th. The tropical Southwest Indian Ocean then lay very quiet until the last week of the month when it became very active. A very broad area of disturbed weather extended from the African coast eastward for several hundred miles. One portion of this disturbed area was identified as Tropical Disturbance 05 by MFR and bulletins were issued from 22 to 24 January. Another disturbance in the Mozambique Channel was numbered Tropical Disturbance 06 and soon developed into Severe Tropical Storm Elita, which crossed the island of Madagascar three times. The easternmost part of the broad disturbed area began to take shape on the 27th and ultimately developed into intense Tropical Cyclone Frank, which fortunately remained well away from any populated areas. At about the same time that Elita and Frank were getting organized, another disturbance began to develop far to the east, just west of longitude 90E. MFR numbered this system as Tropical Disturbance 08, but it soon moved eastward into the Australian Region where it strengthened into Tropical Cyclone Linda. Finally, on 26 January Julian Heming of the UK Meteorological Office sent around some satellite pictures of a low-pressure system well to the south of Madagascar and southeast of southern Africa. According to Julian, the system had emerged off southern Mozambique a couple of days earlier, and while it appeared to have become extratropical, Julian felt that it could have briefly been a tropical cyclone earlier. Roger Edwards felt that at best the system was subtropical, while Roger Edson stated that it looked extratropical to him. David Roth offered the opinion that it appeared to be an occluded system with a well-defined frontal band extending northwestward into southern Africa. In the imagery supplied by Julian, the LOW did exhibit a fairly small and tightly-wound circulation typical of tropical and subtropical cyclones. Reports on Elita and Frank follow. A very special thanks to Kevin Boyle for "travelling" outside his "AOR" and writing the report on Tropical Cyclone Frank. It really helped me out. TROPICAL STORM ELITA (MFR-06 / TC-09S) 26 January - 12 February -------------------------------------------- Elita: contributed by Malawi A. Storm Origins ---------------- The beginnings of the unusual Tropical Storm Elita, which was to cross the island of Madagascar three times, can be traced to an area of convection which formed on 25 January in the Mozambique Channel only about 50 nm off the west coast of Madagascar. Satellite animations indicated the presence of persistent convection over a circulation in the middle and lower levels of the atmosphere. A 200-mb analysis indicated favorable upper-level diffluence but moderate vertical shear over the region. JTWC assessed the development potential as poor. This was raised to fair at 1800 UTC as cycling deep convection continued to increase near the LLCC. MFR issued the first bulletin on Tropical Disturbance 06 at 0600 UTC on 26 January. The disturbance was upgraded to tropical depression status (30 kts) at 26/1200 UTC, and at 1300 UTC JTWC issued a TCFA for the system. JTWC's first warning on TC-09S followed at 1800 UTC. The initial MSW was 35 kts (1-min avg), and a 26/1818 UTC SSM/I pass depicted deep convection wrapping into a well-defined LLCC. At the time TC-09S was centered approximately 215 nm west-northwest of Antananarivo, Madagascar, and drifting east-southeastward at 3 kts. The developing tropical depression was upgraded to tropical storm intensity and named Elita at 0000 UTC on 27 January by the meteorological service of Madagascar. B. Storm History ---------------- Shortly after being named, Tropical Storm Elita embarked on an unusual northward trek through the Mozambique Channel as it was steered by a low to mid-level ridge located to the west. Intensification was rather slow for about 24 hours--in fact, MFR briefly downgraded Elita to depression status at 27/1800 UTC. However, by 28/0000 UTC the storm was beginning to intensify rather rapidly. MFR upped the winds to 40 kts, and JTWC's MSW (1-min avg) jumped from 35 kts at 27/1200 UTC to 55 kts at 28/0000 UTC. Elita reached the northernmost point of its track around 0600 UTC on the 28th when it was centered approximately 85 nm west-northwest of Mahajanga. A ridge to the north and east became the primary steering mechanism and Elita turned east-southeastward toward the west coast of Madagascar as it intensified sharply. At 1200 UTC the storm was centered about 50 nm west-northwest of Mahajanga and the MSW was estimated at 60 kts (per MFR and JTWC). Elita made landfall around 1500 UTC just west of Mahajanga and began to quickly weaken thereafter. JTWC issued their final warning on Elita at 29/0000 UTC, but MFR did not drop the system. It was downgraded to a depression at 29/1800 UTC, but the MFR bulletin noted that deep convective activity was rebuilding over seas in the eastern semicircle. Elita moved southeastward across north-central Madagascar following landfall, and by 0000 UTC on 30 January the center had emerged into the South Indian Ocean just off the east coast. Winds had dropped to 25 kts but MFR forecast the system to re-intensify. After moving offshore the depression drifted southward for about 24 hours, paralleling the eastern coast of Madagascar. MFR re-upgraded Elita to tropical storm status with 40-kt winds at 0000 UTC on 31 January. However, the storm made a westward turn which took it back inland near Mananjary around 0600 UTC. Elita was once more downgraded to depression status at 31/1200 UTC. (JTWC did not issue any warnings during this second phase of Elita's life. A TCFA was issued at 30/2200 UTC, but was cancelled after the system had moved back inland.) The tropical depression moved steadily westward across Madagascar and by 31/1800 UTC was located just inland from the western shoreline about 170 nm west-southwest of Antananarivo. JTWC re-initiated warnings on Elita at this time with the MSW (1-min avg) estimated at 35 kts, based on satellite CI estimates. Significant intensification was forecast since deep convection was increasing and animated water vapor imagery indicated good outflow in both poleward and equatorward directions. After re-emerging into the Mozambique Channel, Elita's motion became northwesterly with gradual slowing in forward speed. The forecast intensification verified--MFR re-upgraded the system to tropical storm status at 1200 UTC on 1 February, and to 45 kts at 1800 UTC. (JTWC's MSW estimate (1-min avg) at 1800 UTC was 55 kts.) Elita was then centered approximately 250 nm west of Antananarivo and its forward motion had slowed to only 3 kts. A mid-level ridge which was building to the north was forecast to become the dominant steering mechanism and ultimately cause Elita to move back eastward toward the coast of Madagascar. The forecast verified--by 0600 UTC on 2 February Elita was moving southeastward. The storm also continued to strengthen. At 1200 UTC MFR upped the intensity to 55 kts, and at 1800 UTC JTWC increased the MSW (1-min avg) to 65 kts, based on CI estimates of 65 and 77 kts. Based on MFR's bulletins, Elita once again reached a peak intensity of 60 kts at 0000 UTC on 3 February, shortly before striking Madagascar's west coast just south of Morondava. The storm began weakening once inland--MFR downgraded it to depression status at 1800 UTC, although JTWC's MSW estimate (1-min avg) was 45 kts. By 0000 UTC on the 4th, the center was back over the waters of the South Indian Ocean, emerging off the coast just south of where it had made its second landfall a few days earlier. Both MFR's and JTWC's forecasts called for Elita to re-intensify, but this was not to be. The system underwent a rapid acceleration early on the 4th--at 0600 UTC the center was located about 350 nm southwest of Reunion Island, moving southeastward at 22 kts. The convection and maximum surface winds had shifted poleward of the exposed LLCC due to the effects of a strengthening upper-tropospheric trough. JTWC issued their final warning on Elita at 04/1800 UTC, placing the center approximately 440 nm southwest of Reunion Island. The tropical storm had been sheared apart and only a fully-exposed LLCC remained. Elita was now tracking slowly southwestward in response to a low-level ridge passing poleward of the system. MFR classified Elita as an extratropical gale at 0000 UTC on 5 February. For the next week the LOW meandered very erratically over the South Indian Ocean to the south and southwest of Reunion Island. A plot of the operational track from MFR's website resembles a tangled strand of spaghetti dropped onto a map from on high. MFR continued issuing warnings on the extratropical LOW since gales were being reported. The system wandered eastward to a point south-southeast of Reunion on the 10th, then began to pick up speed toward the southwest. The final MFR bulletin, issued at 0600 UTC on the 12th, placed the weakening gale about 650 nm southwest of Reunion Island. Elita's crossing Madagascar three times is highly unusual, but not unprecedented. In late January/early February of 1971 Tropical Cyclone Felicie accomplished the same feat. The earlier cyclone actually made four landfalls on the island. Forming near Agalega on 17 January, Felicie struck the northeast coast of Madagascar just south of Vohemar with intense hurricane force winds. Vohemar reported peak gusts reaching 98 kts, which was the instrument's upper limit. A few hours later the anemometer blew down. The town reported 246.3 mm of rain in 24 hours. After emerging into the Mozambique Channel, Felicie moved slowly south- ward paralleling the west coast of Madagascar. The storm described a small counter-clockwise loop on the 24th and 25th which brought the center just onshore south of Besalampy with tropical storm-force winds. Felicie then moved westward, describing a clockwise loop off the coast of Mozambique on the 27th and 28th. The storm then moved eastward and struck the west coast of Madagascar south of Maintirano with hurricane- force winds and torrential rains. After emerging into the South Indian Ocean on 31 January, Felicie then made an abrupt turn to the southwest and struck the coast again, this time near Mananjary. Mananjary reported a peak gust of 80 kts and a 24-hour rainfall total of 218.8 mm. Felicie then re-emerged into the southern Mozambique Channel but soon turned southward and moved into higher latitudes where it lost its tropical characteristics. (This information on Tropical Cyclone Felicie was taken in part from the summary of the 1970-71 tropical cyclone season published by the Mauritius Meteorological Department, and in part from information supplied by Patrick Hoareau--a special thanks to Patrick for sending the data.) C. Meteorological Observations ------------------------------ The only surface observations I have available from Madagascar are from Mahajanga--the point of Elita's first landfall. These were sent by Patrick Hoareau. At 28/1200 UTC the station reported a peak 10-min avg wind of 47 kts, gusting to 78 kts. One hour later the sustained wind had reached 55 kts with a peak gust of 85 kts. At 1400 UTC the MSW reported was 68 kts with a peak gust of 98 kts. Neither MFR nor JTWC were classifying Elita as a hurricane (tropical cyclone), but the synoptic reports from Mahajanga, if verified, certainly suggest that the storm was of hurricane intensity. Mahajanga also reported 248 mm of rain in association with Elita, but I do not know if this represents a storm-period total or a maximum 24-hour rainfall. During the extratropical stage of Elita's long life, strong winds and heavy seas buffeted Mauritius and Reunion Island, although the storm's center was several hundred miles away. Sea-level pressures ranged from 999 to 1002 mb, and the high waves sank one boat. (This information from Thomas Birger--thanks to Thomas for sending it along.) D. Damage and Casualties ------------------------ Elita's three passages across Madagascar proved to be quite damaging to the island. Press reports indicate that 29 persons lost their lives while another 100 were injured. Also, three persons were reported missing. Over 12,400 houses were destroyed, leaving more than 44,000 persons homeless. Roads, water supplies, electricity and communications were disrupted by the storm and its attendant heavy rainfalls. A large percentage of the rice, corn and manioc crops--the food base for much of the population--was destroyed. Also several works of art and national heritage sites were damaged or destroyed. Additional articles on Elita's aftermath in Madagascar can be accessed at the following link: http://www.reliefweb.int/w/rwb.nsf/vLND> (Report written by Gary Padgett) TROPICAL CYCLONE FRANK (MFR-07 / TC-10S) 27 January - 7 February ------------------------------------------- Frank: contributed by the Seychelles A. Storm Origins ---------------------- On 25 January three areas of convection were being monitored by JTWC through the issuance of STWOs. Two were located close to and either side of Madagascar while the third disturbance, which was to become Frank, was located farther to the east, about 700 nm off the northeast coast of Madagascar. Animated multi-spectral satellite imagery showed a weak LLCC associated with the area of convection while an upper air analysis showed a favourable environment with moderate wind shear. The potential for further development was assessed as poor through the 25th and upgraded to fair at 26/1000 UTC following an increase in convection and a better-defined LLCC. Following the appearance of spiral banding JTWC issued a TCFA at 27/0130 UTC and issued the first warning at 1200 UTC on the 27th, estimating the MSW (1-min avg) at 30 kts. At the same time MFR released their first bulletin on Tropical Disturbance 07 with the 10-min avg MSW estimated at 25 kts. B. Storm History ---------------- At the time of the initial warning TC-10S was located approximately 520 nm west-southwest of Diego Garcia and moving very slowly south- southeastward at 2 kts. At 0600 UTC on 28 January both JTWC and MFR upgraded the system to tropical storm intensity, raising their respective intensity estimates to 50 kts (1-min avg) and 40 kts (10-min avg). Steered by a low to mid-level ridge to the south and east, Tropical Storm Frank began to trot towards the south a little more quickly at 8 kts. Prospects for further intensification were good and outflow was being enhanced by two upper-level LOWS centred to the west and southwest. The MSW was raised to 65 kts (MFR followed suit at 1800 UTC) as Frank began the first leg of a cyclonic loop that it was set to undertake over the course of the following two to three days. At 0600 UTC on 29 January Tropical Cyclone Frank was centred 430 nm northeast of Mauritius and moving south-southwest at 5 kts. Further strengthening occurred with Frank becoming a 90-kt storm, but there was no further intensification during the 29th as the system slowly moved southwestward, curving onto a west-northwesterly track by the end of the day. The next day, strengthening had resumed and, based on satellite CI estimates of 102 and 115 kts, JTWC upped the MSW to 105 kts. A further increase saw winds reaching 115 kts, which was maintained through 31 January and the 1st day of February. Enhanced infrared satellite imagery at 31/1800 UTC showed a distinct 15-nm irregular eye. Frank was expected to pick up a little more strength as long as outflow remained favourable. At 0600 UTC on 1 February Tropical Cyclone Frank was tracking eastward at 5 kts some 760 nm southwest of Diego Garcia with a MSW (1-min avg) of 115 kts. A 01/1646 UTC microwave SSM/I pass revealed a small, symmetrical 10-nm eye and this was maintained as Frank reached a peak intensity of 125 kts at 02/0600 UTC. (After peaking at 105 kts (10-min avg) at 30/1800 UTC and 31/0000 UTC, MFR's intensity estimates were falling as JTWC was raising theirs. However, MFR upped the MSW back up to 105 kts at 02/0000 UTC. The lowest CP estimated by Reunion was 925 mb.) The 125-kt peak lasted for approximately 24 hours before the MSW dropped down to 100 kts at 03/0600 UTC, but this intensity was maintained through the 3rd as Frank slowed and turned toward the south- southeast. A second intensification period began, culminating in a second peak of 115 kts (1-min avg) at 04/0600 UTC. Frank had completed a hairpin turn and was now moving rather sluggishly toward the southwest. A gradual weakening set in and this was forecast to continue as the system tracked towards cooler SSTs and heavy shearing conditions. At 0600 UTC on 5 February Frank was moving southward at 3 kts far to the east of Mauritius (700 nm). At this time the MSW fell below 100 kts and further weakening continued with Frank barely at hurricane (cyclone) strength at 0600 UTC the next day. Frank began to accelerate toward the east-southeast as winds fell to tropical storm intensity. The last advisory issued by JTWC located Frank a little over 1000 nm east-southeast of Mauritius, moving east-southeastward in the face of strong easterly shear. Deep convection surrounding the LLCC had all but dissipated and the remnant extratropical system joined up with a weak baroclinic boundary. MFR continue to release bulletins until 1200 UTC on 7 February. C. Damage and Casualties ------------------------ As Tropical Cyclone Frank remained over open waters of the southern Indian Ocean, there were no damage or casualties reported. (Report written by Kevin Boyle) ************************************************************************* NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E Activity for January: 2 tropical cyclones Sources of Information ---------------------- The primary sources of tracking and intensity information for Northwest Australia/Southeast Indian Ocean tropical cyclones are the warnings and advices issued by the Tropical Cyclone Warning Centres at Perth, Western Australia, and Darwin, Northern Territory. References to sustained winds imply a 10-minute averaging period unless otherwise stated. In the companion tropical cyclone tracks file, I occasionally annotate positions from warnings issued by the Joint Typhoon Warning Center (JTWC) of the U. S. Air Force and Navy, located at Pearl Harbor, Hawaii, when they differ from the Australian centres' coor- dinates by usually 40-50 nm or more. The JTWC warnings are also the source of the 1-minute average maximum sustained wind values included in the tracks file. Additionally, information describing details of satellite imagery and atmospheric circulation features included in the narratives is often gleaned from the JTWC warnings. Northwest Australia/Southeast Indian Ocean Tropical Activity for January ------------------------------------------ Two minor tropical cyclones roamed the waters off northwestern Australia and the Southeast Indian Ocean during January. The first, Tropical Cyclone Ken, began as a monsoon depression over land which moved westward into the waters of the Timor Sea. Ken tracked westward for several days as a tropical LOW. It was finally upgraded to a tropical cyclone on the 4th, but only for about 24 hours. The origins of Tropical Cyclone Linda lay west of 90E, where MFR had begun bulletins on the system as Tropical Disturbance 08. However, the LOW moved east- ward into Perth's AOR and was named Linda on 30 January. Linda peaked at 55 kts on the 31st but quickly weakened thereafter as it moved south- ward into a region of strong vertical shear. Reports follow on Ken and Linda. TROPICAL CYCLONE KEN (TC-08S) 1 - 6 January ---------------------------------------- On 30 December the Tropical Weather Outlook from Darwin indicated that a weak 1006-mb LOW was situated in the southern Gulf of Carpentaria. The system was forecast to track westward across the Northern Territory during the following days, but since the system would be over land, no tropical cyclone formation was expected. The next day the LOW was well inland but a monsoon trough lay across northern Australia, and another LOW was expected to form in the trough and moved offshore in a couple of days. The probability for tropical cyclogenesis would then be high. The new LOW appeared well-organized and JTWC issued a TCFA at 1500 UTC on 1 January in anticipation of the LOW's strengthening after it had moved offshore. At 01/0700 UTC Perth began issuing High Seas Weather Warnings and Tropical Cyclone Advices as the system began to slowly move out over the Timor Sea. The initial JTWC warning on TC-08S was issued at 1800 UTC and placed the center of the LOW about 320 nm northeast of Port Hedland and moving westward at 10 kts. The warning intensity of 25 kts was based on CI estimates of 25 and 30 kts. The tropical LOW was fore- cast to track westward over the next couple of days along the equatorial periphery of a mid-level ridge to the southeast. The system continued tracking westward on 2 January. JTWC increased the MSW to 35 kts (1-min avg) at 1200 UTC while a concurrent bulletin from Perth noted that monsoonal gales could be expected in the northern quadrants. Microwave imagery at the time revealed a fully-exposed LLCC approximately 70 nm to the southeast of the deep convection. Little change in intensity was noted on the 3rd, and the system continued marching westward, but turning to the southwest by around 1800 UTC. Dvorak ratings remained around T2.0 and T2.5--35 kts was the peak MSW (1-min avg) assigned by JTWC during the cyclone's life. The south- westerly motion continued on 4 January as an approaching shortwave trough weakened the steering ridge. At 1800 UTC the center was located approximately 250 nm north-northeast of Learmonth, tracking southwest- ward at 4 kts. Some of the CI estimates reached 45 kts on the 4th, and at 1900 UTC Perth upgraded the LOW to Tropical Cyclone Ken with the MSW estimated at 40 kts (10-min avg), which was to be that agency's peak intensity for Ken. Ken tracked steadily south-southwestward on 5 January, reaching a position about 75 nm north-northeast of Learmonth by 1800 UTC. The remarks in the 0600 UTC JTWC warning are very illustrative about the subjectivity of Dvorak analysis: satellite CI estimates at 0600 UTC were 25, 30, 35 and 45 kts. By 1800 UTC CI estimates were 25 and 30 kts, so JTWC decreased the MSW to 25 kts. Perth issued an interim bulletin at 1900 UTC, downgrading Ken to a tropical LOW only 24 hours after it had been named. JTWC issued their final warning on Ken at 1200 UTC on 6 January, placing the weakening 20-kt center approximately 50 nm northwest of Learmonth. The system no longer exhibited any deep convection due to the advection of cooler, drier air as indicated by the presence of cold-air stratocumulus clouds near the center. Also, synoptic and satellite analysis revealed that the former cyclone had taken on the characteristics of a trough. No damage or casualties are known to have resulted from short-lived Tropical Cyclone Ken. (Report written by Gary Padgett) TROPICAL CYCLONE LINDA (TC-11S / MFR-08) 28 January - 1 February ------------------------------------------- An area of disturbed weather developed in the eastern portion of the Southwest Indian Ocean on 27 January. Conditions favored further intensification and JTWC issued a TCFA at 0500 UTC on the 28th with the system located roughly 1000 nm east-northeast of Diego Garcia, or several hundred miles northwest of the Cocos Islands. A microwave pass at 28/0015 UTC indicated that the LLCC was consolidating with deep convection increasing and organizing around the center, although the convection was still somewhat cyclic. A 200-mb analysis indicated moderate upper-level diffluence and weak to moderate vertical shear. At 28/0600 UTC MFR initiated bulletins on the system, identifying it as Tropical Disturbance 08. A microwave pass at 28/1327 UTC revealed a LLCC on the northeastern edge of the cycling deep convection. JTWC issued their first warning on TC-11S at 0000 UTC on 29 January with an initial warning intensity of 35 kts. The LOW's center was located about 400 nm northwest of the Cocos Islands, moving east-southeastward at 10 kts. The system was being steered by westerly flow along the southern periphery of a low to mid-level ridge located north and east of the LOW. Vertical shear over the region was still moderate. TC-11S continued to track south-southeastward on 29 and 30 January. By 30/1200 UTC at least one CI estimate had risen to 45 kts. At 0400 UTC Perth named the system Tropical Cyclone Linda with the MSW estimated at 45 kts (10-min avg). At 1200 UTC Linda's center was only about 70 nm west-northwest of the Cocos Islands, moving southeastward at 8 kts. The center, which previously had been fully-exposed and well- removed from the deepest convection, had become partially-exposed to the northeast of the deep convection. By 31/0000 UTC Linda was located about 160 nm south-southwest of the Cocos Islands and moving southward at 14 kts. The storm had become slightly better organized with deep convection increasing over the LLCC. Perth upped the intensity to 55 kts while JTWC's peak MSW (1-min avg) was 45 kts. By 0000 UTC on 1 February Tropical Cyclone Linda had turned to a south-southwesterly heading about 330 nm south-southwest of the Cocos Islands. The LLCC had become partially-exposed, and further weakening was forecast due to an upper-level trough of cold, dry air to the west. Perth lowered the MSW to 40 kts at 02/0400 UTC, and JTWC dropped their MSW estimate to 35 kts (1-min avg) at 1200 UTC. Linda continued to weaken as it moved south-southwestward across the South Indian Ocean. JTWC dropped the intensity to 35 kts (1-min avg) at 01/1200 UTC as animated multi-spectral imagery revealed an exposed LLCC with no deep convection. Perth downgraded the cyclone and issued their final gale warning at 1600 UTC, and JTWC issued their final warning at 1800 UTC. The weakening system was then located approximately 430 nm south-southwest of the Cocos Islands and still moving slowly toward the south-southwest into an unfavorable environment of confluence and moderate vertical shear. No damage or casualties are known to have resulted from Tropical Cyclone Linda. (Report written by Gary Padgett) ************************************************************************* NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E Activity for January: 1 overland monsoon depression Sources of Information ---------------------- The primary sources of tracking and intensity information for Northeast Australia/Coral Sea tropical cyclones are the warnings and advices issued by the Tropical Cyclone Warning Centres at Brisbane, Queensland, and Darwin, Northern Territory, and on very infrequent occasions, by the centre at Port Moresby, Papua New Guinea. References to sustained winds imply a 10-minute averaging period unless otherwise stated. In the companion tropical cyclone tracks file, I occasionally annotate positions from warnings issued by the Joint Typhoon Warning Center (JTWC) of the U. S. Air Force and Navy, located at Pearl Harbor, Hawaii, when they differ from the Australian centres' coor- dinates by usually 40-50 nm or more. The JTWC warnings are also the source of the 1-minute average maximum sustained wind values included in the tracks file. Additionally, information describing details of satellite imagery and atmospheric circulation features included in the narratives is often gleaned from the JTWC warnings. Northeast Australia/Coral Sea Tropical Activity for January ----------------------------- No tropical cyclones occurred over waters of the Gulf of Carpentaria and Coral Sea during January. A large low-pressure system which began in late December was causing gales over a wide area just west of 160E as the month opened, but the system had weakened to below gale force by 2 January. More information on this system can be found in the December tropical cyclone summary. The only other significant system during January was a monsoon depression which formed near the south- western corner of the Gulf of Carpentaria, subsequently moving south- eastward across Queensland and part of New South Wales. The LOW brought heavy rainfall to an extensive area, which although helping to relieve drought conditions in many areas, nonetheless was responsible for widespread flooding. Following is a report on this system written by Simon Clarke--a special thanks to Simon for his assistance. MONSOON DEPRESSION 10 - 17 January -------------------------------------- A significant monsoon LOW formed over land in the Arnhem Land district of the Northern Territory on 10/11 January 2004. This LOW was responsible for dragging a deep layer of unstable tropical moisture from the Coral Sea and producing a significant rain event across much of drought-ravaged Queensland and into some parts of New South Wales over the following week. By 12 January 2004, the LOW had blanketed parts of the Northern Territory Top End with heavy rain. In the Northern Territory, Limmen River, near the southwest corner of the Gulf of Carpentaria, recorded 187.2 mm in the 24 hours ending at 9 AM. Nearby on the north coast, Jabiru recorded 101.2 mm and Oenpelli 94.8 mm. The LOW gave general falls of between 100 mm to 300 mm to the northern parts of the Territory, with moderate flooding in the middle reaches of the Daly River in the Territory's northwest. The monsoon LOW deepened to 998 hPa and by 13/0600 UTC was tracking inland close to the southeastern Gulf of Carpentaria on a south- southeasterly path. By 15/0600 UTC the LOW had moved slowly through the northwestern and inland central regions of Queensland maintaining intensity at 996 hPa. On 15 January Mount Isa, Queensland, reported its highest daily rainfall record of 198 mm in the 24 hours to 9 AM since observations commenced in 1926 (previous record was 157.5 mm on 14 January 1957). The highest 24-hour report was 246 mm at Moondarra. The LOW produced widespread flooding in all the western rivers of Queensland with major road links being cut and forcing air drops of food supplies. During this period, the Bureau of Meteorology issued severe weather warnings for strong winds and torrential rain mainly for the area to the south and east of the LOW. By 0600 UTC on 16 January the LOW had commenced a southeastward acceleration while still delivering heavy falls of up to 200 mm through central Queensland. The Queensland Government activated natural disaster relief arrangements for up to ten shire council areas, while food and medical supplies were delivered to isolated properties. About 4000 sandbags were transported to Longreach to protect homes from flooding. During the following 24-hour period, the LOW crossed the border into New South Wales north of Lightning Ridge. The LOW's well-defined circulation broke down as it crossed the Great Dividing Range. The LOW moved seaward near Sydney, reformed and swept rapidly away to the south-southeast across the Tasman Sea. The system brought moderate to heavy falls to parts of inland New South Wales. However, the monsoon LOW will be remembered for bringing the wettest January to many Queens- land centres since the extensive floods of 1974, amongst them Brisbane City (279 mm), Emerald (211 mm), Longreach (199 mm) and Mt Isa (392 mm). Many thanks to Laurier William whose excellent summary of this major event can be found at the following link. Here you will find extensive charts, graphs and further in-depth details of the event by clicking on the daily reports for 12-17 January 2004: http://www.australianweathernews.com/index.shtml> (Report written by Simon Clarke) ************************************************************************* SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E Activity for January: 1 intense tropical cyclone Sources of Information ---------------------- The primary sources of tracking and intensity information for South Pacific tropical cyclones are the warnings and advisories issued by the Tropical Cyclone Warning Centres at Nadi, Fiji (for waters north of latitude 25S), and Wellington, New Zealand (for waters south of latitude 25S). References to sustained winds imply a 10-minute averaging period unless otherwise stated. In the companion tropical cyclone tracks file, I occasionally annotate positions from warnings issued by the Joint Typhoon Warning Center (JTWC) of the U. S. Air Force and Navy, located at Pearl Harbor, Hawaii, when they differ from the Southern Hemisphere centres' coordinates by usually 40-50 nm or more. The JTWC warnings are also the source of the 1-minute average maximum sustained wind values included in the tracks file. Additionally, information describing details of satellite imagery and atmospheric circulation features included in the narratives is often gleaned from the JTWC warnings. South Pacific Tropical Activity for January ------------------------------------------- Warnings were issued from the Nadi, Fiji, office for only one tropical system during January, but it was a monster. The disturbance began to the north of Fiji in late December, but drifted slowly eastward for several days before developing significantly. It was upgraded to Tropical Cyclone Heta on 2 January, and was destined to become a very intense tropical cyclone. Heta caused some damage to Samoa as it moved very slowly southward a short distance to the west of Savai'i, but the greatest damage was done to the tiny island nation of Niue--the world's smallest nation. The island was devastated, and there were concerns that there might be such a drop in population that Niue might have to return to being a New Zealand territory after having been independent for 30 years. A special thanks to Simon Clarke for authoring the following report on Tropical Cyclone Heta. TROPICAL CYCLONE HETA (TD-03F / TC-07P) 28 December - 11 January -------------------------------------------- A. Storm Origins ---------------- Heta was the first tropical cyclone to form in RSMC Nadi's area of responsibility during the 2003/2004 South Pacific tropical cyclone season. Continuing the trend of powerful Southeast Pacific storms established during the 2002/2003 season, Heta achieved very intense Category 5 tropical cyclone status with maximum (10-minute average) winds estimated at about 115 knots and momentary gusts of up to 160 knots at its peak intensity. The system which eventually developed into Heta originated in the area midway between Rotuma and Fiji on 25 December 2003 and was identified as Tropical Disturbance 03F. It moved slowly eastward in the area just north of Fiji, gradually developing into a tropical depression on 28 December. The depression continued to move north- eastward to just west of Atufu, the northernmost of the Tokelau Islands, by 2 January 2004. It was named Tropical Cyclone Heta at 0300 UTC on 2 January when located approximately 400 nautical miles east of Funafuti Atoll. B. Storm History ---------------- Once named, Heta intensified rapidly while moving into an area with weak shear (5-10 kts), excellent divergence aloft and SSTs of 29 C. Under a weak steering regime, Heta turned slowly southward. The cyclone reached storm intensity around 02/1200 UTC and hurricane intensity around 0600 UTC on 3 January. Peak intensity was attained at approximately 05/0000 UTC when the centre was passing about 70 nautical miles to the west of Savai'i, Samoa, or about 135 nautical miles west of Apia, Samoa. At the time, maximum (10-minute) average winds were approximately 115 knots close to the centre with peak gusts estimated at 160 knots. This intensity was maintained over the next 24 hours as Heta turned to a southeastward track, accelerating to approximately 20 knots. This track took the cyclone centre to within about 50 nautical miles northeast of Niuatoputu in the northern Tonga Group around 05/1200 UTC, and very close to the west of Niue around 0300 UTC on 6 January. At 0300 UTC Heta was centred approximately 35 nm west-northwest of Alofi, Niue. Heta moved out of RSMC Nadi's area of responsibility soon after 07/0000 UTC, maintaining its southeastward movement at about 20 knots while gradually weakening. RSMC Wellington took over the responsibility for warnings as Heta weakened under increasing vertical wind shear. Heta had become extratropical by 2300 UTC on 7 January when located about 525 nautical miles south of Rarotonga. The strong extratropical storm became quasi-stationary in that area and ultimately began to drift slowly westward. The final reference to the system in Wellington's marine warnings was at 2300 UTC on the 11th. At that time the former intense cyclone was a weakening 35-kt gale located approximately 1250 nautical miles east of Norfolk Island. (Editor's Note: The peak MSW (1-min avg) reported by JTWC for Tropical Cyclone Heta was 140 kts, based on a Dvorak rating of T7.0. The minimum estimated CP as reported by Nadi was 915 hPa.) C. Meteorological Observations ------------------------------ Before meteorological instruments at the Niue Meteorological Station failed, the minimum atmospheric pressure recorded was 945 hPa at 06/0411 UTC. (Editor's Note: There was also an e-mail from Jeff Callaghan which mentioned a pressure of 933.5 hPa at 1705 local time on 5 January.) Further data from Niue may be found at: http://www.niue.nu/wx/weekrep.htm)> This site shows that several records were broken during the passage of Heta. Included are: Record high wind gust: 286.8 km/hr (155 knots) from 061 deg at 14:37 (local time) on 05 January 2004 Record high average speed: 181.3 km/hr (98 knots) from 078 deg at 14:45 (local time) on 05 January 2004 Record daily rain: 999.2 mm on 05 January 2004 (Please note: It is neither clear how long meteorological data has been recorded at this site nor how well the instruments have been calibrated for extreme conditions) D. Damage and Casualties ------------------------ Heta caused destructive storm force winds and associated sea flooding over northern and western parts of Samoa with one death reported. Also destructive storm force winds occurred over Niuatoputapu in Tonga. However, it was Niue which was to bear the brunt of the very destructive hurricane force winds and associated extremely very high sea waves. These caused extensive and severe damage that was reported to be the worst seen in Niue in living memory. Amazingly, only one death on the island was directly attributed to the cyclone. Images of Heta from Niue are available at Geoff Mackley's web site at: http://www.rambocam.com/heta.html> At the time of this report, no information on damage was available from Tokelau, Wallis or Futuna. In Samoa, there was extensive damage to houses, power lines and crops due to heavy swells and sea flooding. One person was swept out to sea and was presumed dead. Airline schedules were also disrupted. In Niue, it appeared that at least as much damage was caused by the extremely high sea waves as by the wind. Crops and island vegetation were wiped out in the salt-laden winds. Media reports describe how the capital, Alofi, bore the brunt of the cyclone with half of the commercial area wiped out. Houses built atop 30-metre cliffs and others thought to be safe up to 100 metres inland were destroyed. According to these reports, worst hit was the southern area of Aliluki where monstrous waves, rather than the wind, appear to have been the main cause of the devastation. A woman was killed when a large wave smashed into the house where she and her 19-month-old son were sheltering. The boy received serious injuries, and despite evacuation to an Auckland Hospital (New Zealand), died some days later from skull injuries and lacerations. Communication to and from Niue was completely severed and the only contact available was by satellite phone several days after the passage of the cyclone. Much of the infrastructure on the island was destroyed. Buildings and houses were either demolished or severely damaged, subsequently releasing poisonous asbestos. An estimate of the total damage to Niue is 50 million New Zealand dollars (NZ $50 million). In the aftermath of the storm, some island leaders are calling for a return to New Zealand governance, and expect the population to fall from about 1200 native Niueans to an unsustainable 500 people. Such a drop would likely render the nation unviable. Niueans had been adamant they wanted to retain the status quo, i.e., financial and administrative support from New Zealand while retaining their own sovereignty. But, as the smallest independent state in the world, its constitutional status remained "under review". Niue has been self-governing in free association with New Zealand since 1974, and New Zealand has an ongoing responsibility to provide necessary economic and administrative assistance. Further information relating to the destruction wrought by Heta can be found at the following URLs: http://www.reliefweb.int/w/rwb.nsf/vID/9E57898DCFE96A8AC1256E20003D3C DD?OpenDocument> and, http://www.reliefweb.int/w/rwb.nsf/vID/8445C982218B9A8C49256E16001F8E AE?OpenDocument> A further interesting (though not rigorously vetted) account of Heta can be found at http://www.seafriends.org.nz/indepth/nd010.htm> (Report written by Simon Clarke, with additional information supplied by Alipate Waqaicelua and Jeff Callaghan) ************************************************************************* 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: summ0401.htm
Updated: 26th October 2006 |
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