====================== TYPHOON '99 ARCHIVES ====================== MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY JANUARY, 1999 (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.) NOTE: I have been informed of another website where past editions of the summaries and track files are archived. The owner of the site is Michael Pitt, and the URL is: Thanks to Michael for archiving the summaries and for making me aware of it. *********************************************************************** 1999 TROPICAL CYCLONE NAMES FOR THE NORTHWEST PACIFIC BASIN Two lists of tropical cyclone names are used for the Northwest Pacific basin, which is normally the most active of all the tropical cyclone basins. The names most familiar to the international community are the names assigned by JTWC (formerly located on the island of Guam but now re-located to Pearl Harbor on the island of Oahu in Hawaii). The Joint Typhoon Warning Center (joint between the U. S. Air Force and Navy) was founded in 1959, but U. S. Navy typhoon forecasters had been naming tropical cyclones in the Western Pacific since at least 1945. For the most part, English feminine names were used until 1979, when men's names were introduced and alternated with women's names. The other set of names are Filipino women's names, all ending with the letters "ng", which are assigned by PAGASA for depressions and storms which either form in or move into PAGASA's area of warning responsibility. This practice dates back to 1963, and the names are intended only for internal use within the Republic of the Philippines. They are not attached to any international high seas warnings. However, the winds of change are blowing. The year 1999 will be the last year either of these lists of names are used. Beginning in 2000 a new truly international list of names will be introduced for naming of tropical cyclones in this basin. Fourteen nations or territories contributed 10 names each, and these will be allotted to tropical cyclones as they reach tropical storm intensity by the Japanese Meteorological Agency's Typhoon Warning Centre, which is the WMO Regional Specialty Meteorological Centre (RSMC) for the region. Names for 1999 are (an asterisk indicates name has already been assigned since 1 Jan): JTWC Names - Hilda *, Iris *, Jacob, Kate, Leo, Maggie, Neil, Olga, Paul, Rachel, Sam, Tanya, Virgil, Wendy, York, Zia, Ann, Bart, Cam, Dan, Eve, Frankie, Gloria, Herb, Ian, Joy, Kirk, Lisa, Marty, Niki, Orson, Piper, Rick, Sally, Tom, Violet, Willie, Yates, Zane PAGASA Names - Auring *, Bebeng *, Karing, Diding, Etang, Gening, Helming, Ising, Luding, Mameng, Neneng, Oniang, Pepang, Rening, Sendang, Trining, Ulding, Warling, Yayang, Ading, Barang, Krising, Dadang, Erling, Goying *********************************************************************** JANUARY HIGHLIGHTS --> Vanuatu struck by damaging South Pacific cyclone --> Southwest Indian Ocean season gets underway *********************************************************************** ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for January: No tropical cyclones *********************************************************************** 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: 1 tropical storm ** ** - This based upon JTWC's classification--JMA and PAGASA did not classify Hilda/Auring as a tropical storm. NOTE: Most of the information on each cyclone's history presented in the narrative will be based upon JTWC's advisories, and references to winds should be understood as a 1-min avg MSW unless otherwise noted. However, in the accompanying tracking document I have made comparisons of coordinates with JMA (Japan) and the Philippines (PAGASA) when their positions differed from JTWC's by usually 40-50 nm or more. Also, as announced earlier in a separate posting, a column of 10-min avg MSW is included--the values being obtained from either PAGASA's or JMA's advisories. A special thanks to Michael V. Padua, owner of the Typhoon '99 webpage, for sending me the PAGASA tracks. In the title line for each storm I plan to reference all the cyclone names/numbers I have available: JTWC's depression number and name (if any), JMA's tropical storm numeric designator, and PAGASA's name for systems forming in or passing through their area of responsibility. Tropical Storm Hilda/Auring (TD-01W) 3 - 8 January ------------------------------------- The first Northwest Pacific basin tropical cyclone of 1999 wasted no time in making its appearance. As early as 1 Jan the Significant Tropical Weather Outlooks issued by JTWC were mentioning a disturbance in the extreme southern portion of the South China Sea west of Borneo. JMA classified the LOW as a tropical depression at 1800 UTC on 3 Jan, locating the ill-defined center about 350 nm southeast of Ho Chi Minh City, Vietnam. The next bulletin, however, re-located the center about 125 nm to the east. JTWC issued a Formation Alert for the area at 0200 UTC on the 4th. The system was quite near the northwest coast of Borneo and some mid-level dry air entrainment helped to retard development of the depression. The first JTWC warning, issued at 04/0600 UTC, estimated the center to be about 500 nm east-southeast of Ho Chi Minh City. The initial intensity was set at 25 kts based upon visible and infrared satellite imagery estimates and rawinsonde data indicating 30 to 35-kt winds in the area from 600 to 1800 m. The depression moved very slowly and erratically, generally drifting very slowly northward and away from Borneo. The center was ill-defined and difficult to track--a plot of the center positions from JTWC and JMA look like randomly scattered dots. The tracking was made more difficult by the presence of numerous weak low-level vortices embedded within a broader circulation over the South China Sea. JTWC increased the MSW to 30 kts at 0600 UTC on 5 Jan based upon a 0000 UTC ship report of 30 kts northwest of the center. A 06/0000 UTC report of 30-kt winds southwest of the center from ship VSBZ as well as satellite intensity estimates of 30-35 kts were the basis for upgrading the depression to Tropical Storm Hilda at 0600 UTC on the 6th. Hilda was at that time centered about 600 nm southwest of Manila. The weak storm drifted slowly northward but did not strengthen further. By 0000 UTC on 7 Jan the low-level circulation had broadened considerably and resembled an elongated trough. The deep convection was well northeast of the low-level center and synoptic data from ships indicated winds of only 25 kts, so Hilda was downgraded to a tropical depression and JTWC wrote the final warning. JMA continued to track the residual depression on through 08/0600 UTC as the weak system turned to a general easterly direction toward the Philippine island of Palawan. As would be expected with such an ill-defined system, there were often significant discrepancies between JTWC's and JMA's positions. PAGASA issued only three advisories on this system, naming it Auring. Neither PAGASA nor JMA classified the depression as a tropical storm. *********************************************************************** NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for January: No tropical cyclones *********************************************************************** SOUTH INDIAN OCEAN (SIO) - South Indian Ocean West of Longitude 90E Activity for January: 1 tropical disturbance 2 moderate tropical storms 1 severe tropical storm The primary sources of information upon which the narrative is based are the warnings issued by the TCWC on La Reunion Island, associated with Meteo France, and which is the RSMC for the South Indian Ocean basin. However, cyclones in this region are named by the sub-regional centres on Mauritius and Madagascar with longitude 55E as the dividing line between their respective areas. La Reunion only advises these centres regarding the intensity of tropical systems. References to sustained winds should be understood as meaning a 10-min averaging period unless otherwise stated. In the accompanying track file some position comparisons have been made with JTWC's positions, and warnings from JTWC were used as a source of 1-min avg MSW estimates. (A special thanks to Philippe Caroff of the La Reunion TCWC for sending me an analyzed Best Track File for Alda, Birenda, and Chikita. This information forms the basis for the tracking information given for Alda and Birenda in the accompanying track file.) Tropical Disturbance "A4" 4 - 6 January ------------------------- A Tropical Weather Outlook issued by JTWC on 1 Jan mentioned an area of convection near the coast of Mozambique. A large cyclonic circulation was located near Zimbabwe and Mozambique with an upper- level anticyclone over the area. The low-level circulation was over land but drifting eastward toward the Mozambique Channel. During subsequent days the area moved out over the warm waters of the Channel, and the La Reunion TCWC initiated tropical disturbance bulletins at 04/1200 UTC, placing the center about 225 nm northwest of Tulear on the southeast coast of Madagascar. The bulletin indicated that squally weather existed up to 250 nm from the center in the northern and eastern sectors. Outflow was good over the eastern half of the system but restricted on the western side where vertical shear was inhibiting development. The LOW moved generally in a south-southeasterly direction, passing about 100 nm west of Tulear at 0000 UTC on 5 Jan. Maximum winds in this disturbance as reported by La Reunion were 30 kts, but these were mainly well away from the center in the eastern semi-circle and associated with a strengthening gradient between the LOW and a ridge to the southeast. The system passed a short distance southwest of the southern portion of Madagascar early on the 5th. La Reunion classified the disturbance as a subtropical cyclone at 1200 UTC and as an extratropical depression six hours later as it began to accelerate south-southeastwards into the South Indian Ocean. Severe Tropical Storm Alda (TC-12S) 14 - 19 January ------------------------------------ The second disturbance to form in the Mozambique Channel in less than two weeks was first mentioned by JTWC on 12 Jan. Deep convection near the coast of Mozambique was forming near a shear line associated with an extratropical LOW to the south. Synoptic data suggested that a low-level circulation center was located farther inland with convergence contributing to the deep convection. MSW at this time were estimated to be only 15-20 kts. By 14 Jan the area of deepest convection was out over the Channel and La Reunion initiated warnings on the system, classifying it as a subtropical cyclone due to the lack of persistent central convection. Squally weather extended out from 200-300 nm to the south and east of the center which was located about 450 nm west-northwest of Tulear. The disturbance remained quasi-stationary for a day or so before commencing a very slow eastward drift. Moderate vertical windshear across the region initially kept the convection from organizing near the center. By 16/0600 UTC the disturbance had reached the central portion of the Mozambique Channel and had become slightly better organized to the extent that La Reunion classified it as a tropical disturbance. The system turned slowly to the south and began to intensify, becoming Tropical Storm Alda at 1800 UTC on the 16th. Neither JTWC nor La Reunion expected the storm to intensify further, and JTWC dropped warnings after 17/1500 UTC. Alda continued moving slowly to the south, passing about 200 nm west of Tulear at 0000 UTC on 17 Jan. The JTWC warning for 17/1500 UTC noted that the satellite current intensity was 25 kts but that there were reports from ships of winds to 40 kts. Convection became much better organized on the 17th, and satellite imagery at 18/0600 UTC showed an eye-pattern in spite of the northwesterly shearing. Alda reached its peak intensity of 50 kts at 1200 UTC on 18 Jan when it was centered about 375 nm southwest of Tulear. After this, however, the storm began to accelerate to the southeast and started to lose its tropical characteristics. La Reunion declared Alda to be extratropical and wrote the last warning at 0600 UTC on 19 Jan with the center estimated to be about 700 nm east of Durban, South Africa. (After dropping warnings on the storm at 17/1500 UTC, JTWC issued one more warning at the time Alda reached its peak intensity. JTWC's 1-min MSW estimate was 55 kts--in excellent agreement with La Reunion's reported 10-min MSW of 50 kts.) Severe Tropical Cyclone Damien/Birenda (TC-15S) 20 January - 7 February ------------------------------------------------ Weakening Tropical Cyclone Damien entered the South Indian Ocean basin around 0600 UTC on 28 Jan at a point about 475 nm southwest of Cocos Island and was renamed Birenda by the Mauritius Meteorological Service. The early portion of this cyclone's history is discussed in the section of this summary covering the Australian Region. When it entered the basin Damien/Birenda was moving on a west- southwesterly track which eventually turned into a more-or-less westerly heading. By the 29th animated infrared and water vapor imagery revealed that the upper-level cirrus from the convection was being advected to the southeast in front of an approaching upper-level trough. Birenda was downgraded to a tropical depression by 1200 UTC, though JTWC still carried the system as a tropical storm through 1800 UTC on 30 Jan. By then the low-level circulation was completely exposed and the nearest convection was in a convergent band 180 nm to the west. The strongest winds were on the south side due to the translational movement and the pressure gradient between the storm and an anticyclone to the south. The best track from La Reunion shows the weak remnants drifting west-northwestward for a few days, finally being dropped at 03/0000 UTC when located about 750 nm east-northeast of Mauritius. JTWC continued to mention the renmants for a few days in their daily Tropical Weather Outlooks through 7 Feb when the system had merged with a monsoon trough near 13S, 49E. Tropical Storm Chikita (TC-17S) 29 January - 5 February -------------------------------- A tropical disturbance following in the tracks of Damien/Birenda moved from the western portion of the Australian Region across 90E in late January. It began to intensify quite rapidly on 31 Jan and was named Tropical Storm Chikita by Mauritius at 1200 UTC. Since most of Chikita's lifespan occurred in February, it will be covered in the February summary. *********************************************************************** AUSTRALIAN REGION (AUG) - From Longitude 90E Eastward to Longitude 160E Activity for January: 1 tropical LOW (depression) 2 tropical cyclones of storm intensity 1 severe tropical cyclone The primary sources of information for Australian Region tropical cyclones are the warnings and bulletins issued by the three TCWC's at Perth, Darwin, and Brisbane. Information gleaned from JTWC's warnings is used as a supplement for times when it was impossible to obtain Australian bulletins and for comparison purposes. Additionally, some information came from the Monthly Report of the RSMC at Darwin, Northern Territory. References to sustained winds should be understood as being based on a 10-min averaging period unless otherwise noted. Mr. Matthew Saxby, a tropical cyclone enthusiast from Queanbeyan, New South Wales, Australia, is going to assist me with collecting information and preparing tracks for tropical cyclones in the Australian Region. Some of the information contained in the narratives is based upon information forwarded to me by Matthew. A special thanks to Matthew for his assistance. Tropical Cyclone Olinda (TC-13P) 19 - 24 January --------------------------------- A Significant Tropical Weather Outlook from JTWC at 0600 UTC on 19 Jan mentioned an area of disturbed weather south of the Solomon Islands. Maximum winds at the time were estimated to be only around 25 kts (1-min avg). The system moved to the southeast and by 20 Jan had gotten better organized. Brisbane located the center of the LOW to be about 700 nm east of Cairns, or about 550 nm west-northwest of Noumea, New Caledonia, at 1200 UTC. At the same time JTWC issued the first warning on the system based on surrounding synoptic reports of 25-kt winds (10-min avg). The depression had developed impressive outflow with some spiral banding features. It still at this stage had some monsoon depression characteristics in that maximum winds were located along the outer periphery of the circulation. The LOW drifted south-southeastward and slowly became better organized. Later on 21 Jan the system began to organize rapidly into a more consolidated system. Brisbane named the LOW Tropical Cyclone Olinda at 1800 UTC when it was centered approximately 425 nm west- northwest of Noumea. This position was just west of 160E and Olinda had soon moved into Fiji's AOR and into the Southwest Pacific basin. For a discussion of the remainder of Olinda's history, see the section of this summary covering the Southwest Pacific basin. Tropical Cyclone Pete (TC-14P) 20 - 27 January ------------------------------- While the pre-Olinda system was getting organized on 20 Jan several hundred miles east of the Australian coast, another area of disturbed weather moved from northeastern Queensland out into the Coral Sea. This LOW began to develop in tandem with the other disturbance farther east and was named Tropical Cyclone Pete only 18 hours after Olinda was christened. The LOW was centered about 200 nm east-northeast of Cooktown at 0000 UTC on 21 Jan. According to the Monthly Summary from Fiji, the depression executed an anti-clockwise loop late on the 21st. A plot of the six-hourly coordinates does not definitively describe a loop, so it must have been a very tight one. Following this wobble the LOW began to move on a general southeasterly track very similar to that taken by Olinda, lying southwest of and roughly parallel to the earlier cyclone's path. JTWC initiated warnings at 22/0600 UTC upon receipt of a ship report of 40-kt winds. Brisbane named the system Tropical Cyclone Pete six hours later when it was centered about 400 nm east of Cairns. Pete continued to intensify some and reached its peak intensity of 50 kts at 0600 UTC on the 23rd when it was located about 600 nm east of Townsville. The cyclone continued on its southeastward course and had moved out of the Australian Region by 24/0000 UTC. For a discussion of the remainder of Pete's history, see the section of this summary covering the Southwest Pacific basin. Severe Tropical Cyclone Damien/Birenda (TC-15S) 20 January - 7 February ------------------------------------------------ A disturbance southwest of Sumatra associated with a monsoon trough lying across the central Indian Ocean was noted in a Tropical Weather Outlook from JTWC on 17 Jan. During the following days the area of convection migrated slowly east-southeastward. Synoptic data from ships indicated a weak, low-level circulation existed, and satellite imagery indicated that the disturbance had good outflow to the west. JTWC continued to mention the system in their daily Outlooks, and Perth began issuing bulletins on the disturbance at 2200 UTC on 21 Jan. The LOW had drifted eastward south of Java and by this time had become quasi-stationary about 600 nm northwest of Onslow in Western Australia, or about 350 nm east-southeast of Christmas Island. On 22 Jan the LOW began moving west-southwestward under the influence of a subtropical ridge to its south and slowly intensified in a moderate shear environment. By 2200 UTC Tropical Cyclone Damien had been christened about 200 nm southeast of Christmas Island. MSW at this time were estimated at 45 kts. Damien continued on a west- southwesterly course for the next few days and reached a peak intensity of almost 80 kts around 24/2200 UTC when it was centered about 225 nm south-southeast of Cocos Island. In satellite imagery the cyclone alternated between displaying a clearly visible eye and an embedded center pattern. However, the cyclone's peak intensity did not last long. On the 25th Damien weakened considerably as convection waned and vertical shear increased. Satellite images indicated that a large field of cold-air stratocumulus had wrapped into the system, thereby acting to decrease the central convection. The cyclone turned to a temporary slow northwesterly course on 25 Jan which continued until the 27th. By 1600 UTC on that date Damien was beginning to move southwestward once more. The weakening cyclone crossed 90E into the Mauritius/La Reunion area of responsibility around 28/0600 UTC. MSW by this time were down to 40 kts and the low-level center was fully exposed with the nearest convection about 70 nm to the southwest. Synoptic data and a scatterometer pass indicated a fairly large and symmetric 35-kt wind radius. Perth issued the last warning at 0400 UTC on 28 Jan with Damien's center estimated to be about 475 nm southwest of Cocos Island. Upon entering the South Indian Ocean basin, the cyclone was renamed Birenda by Mauritius. The latter part of this system's history is discussed in the portion of this summary covering the South Indian Ocean cyclone basin. Tropical LOW (TC-16P) 22 - 27 January ---------------------- While Tropical Cyclones Olinda and Pete were racing southeastward across the South Pacific, another disturbance was slowly getting organized in the Gulf of Carpentaria. JTWC began mentioning the area in their daily Tropical Weather Outlooks on 22 Jan. The disturbance apparently drifted from north of Arnhem Land eastward into the northern Gulf. The Darwin TCWC began issuing warnings on the LOW at 0600 UTC on 24 Jan when the system was centered about 115 nm east- northeast of Nhulunbuy. A cyclone watch was posted at 0730 UTC for portions of the southern Gulf Coast since it was anticipated that the LOW would develop into a tropical cyclone within the next 24 hours. JTWC issued a Formation Alert at 24/0930 UTC and began issuing warnings at 0600 UTC on 25 Jan when the center was about 110 nm east of Nhulunbuy or 175 nm northeast of Alyangula. The depression was located within an elongated monsoon trough lying across northern Australia. Over the next couple of days the system drifted very slowly in a general southerly or south-southwesterly direction. It appeared to get a little better organized on 25 Jan, but by the 26th had run into some vertical shear and was weakening. The 26/2100 UTC warning from JTWC noted that a second circulation appeared to be east of the warning position and that dry air entrainment had led to decreased organization of the depression. The LOW was located 125 nm east of Alyangula at 0000 UTC on 26 Jan and Darwin issued the last gale warning at 1800 UTC, although they continued to issue Tropical Cyclone Advices for another 24 hours. The final Advice from Darwin, at 27/1930 UTC, placed the weakening center about 105 nm east-southeast of Alyangula or an equal distance northeast of Port McArthur, moving slowly southeastward. *********************************************************************** SOUTHWEST PACIFIC (SWP) - South Pacific Ocean East of Longitude 160E Activity for January: 2 tropical cyclones of storm intensity 1 tropical cyclone of hurricane intensity NOTE: Most of the information presented below was taken from the operational warnings and advisories issued by the Fiji TCWC at Nadi and from the Monthly Summary for January prepared by Alipate Waqaicelua, Principal Scientific Officer and Chief of the forecasting group. A special thanks to Alipate for sending the summary to me. References to sustained winds imply a 10-minute averaging period unless otherwise noted. Also, the basic definition of a cyclone in WMO Region 5 (Australia and the South Pacific) has the unique requirement that a depression must have gale-force winds more-or-less completely surrounding the center before the system is named as a tropical cyclone. Hence, often gales of 35-40 kts may be present in one or two quadrants but the system is not considered a tropical cyclone. Fiji this season has initiated their own numbering scheme for tropical disturbances (01F, 02F, etc) that form in the Nadi AOR. Some of the numbered disturbances never warrant depression status. A description of some of these weaker disturbances can be found following the discussion of Tropical Cyclone Pete. Tropical Cyclone Dani (TC-07F / TC-11P) 13 - 24 January ---------------------------------------- The first named South Pacific system of 1999 was a major cyclone. The TCWC at Nadi, Fiji, identified a weak disturbance embedded in a monsoon trough just south of the Solomon Islands on 13 Jan. The disturbed area was drifting southeast. By 0600 UTC on 14 Jan the system had become sufficiently organized that JTWC initiated warnings, locating the center about 300 nm northwest of Port Vila, Vanuatu, with 35-kt MSW (1-min avg). The system continued to move generally southwards off to the west of Espiritu Santo Island, the largest island in the Republic of Vanuatu. By 15/0600 UTC convective organization had increased significantly with the low-level center being covered by deep convection which was cooling and expanding spatially. Most TCWC's were by now giving the depression a Dvorak number of T=3.0, so Nadi named the system Tropical Cyclone Dani, locating it about 200 nm west of Port Vila. About the time that Dani reached tropical cyclone intensity, a 500-mb ridge to the south strengthened, thereby preventing any further poleward movement. Dani drifted slowly to the west on the 16th as it rapidly strengthened. Storm intensity (47 kts) was reached by 15/1800 UTC, and hurricane intensity six hours later. The cyclone had by this time drifted westward to a point about 250 nm west of Port Vila. Dani then began a slow northward motion as it came under the influence of a mid-level anticyclone to its northwest. The cyclone reached its peak intensity of 95 kts MSW (110 kts 1-min avg from JTWC) by 0000 UTC on 17 Jan when it was centered about 325 nm west-northwest of Port Vila or about 150 nm west of Espiritu Santo Island. Dani was by now moving northward at a slightly faster pace and began to curve more to the northeast as the anticyclone to its northwest extended a ridge to the northeast. The storm also weakened slightly (to 80 kts), likely due to interaction with a disturbance within the SPCZ. As the ridge to the north strengthened Dani turned more to the east, reaching the northernmost point of its track at 18/0000 UTC when it was located 150 nm northwest of the northern tip of Espiritu Santo Island. After this point the cyclone began turning slowly to the south as the main steering influence shifted from the ridge to its north to the mid-level ridge to its east and southeast. Dani moved on a southeasterly course through 0000 UTC on the 19th, then turned due south and struck the island of Espiritu Santo around 0300 UTC near Hog Harbour with winds of hurricane intensity. Interaction with the rugged terrain weakened the storm slightly, but it re-intensified back to a MSW of 80 kts as it accelerated towards the south. The cyclone brushed by the Vanuatuan islands of Malekula and Efate, passing about 50 nm west of Port Vila at 20/0000 UTC. As Dani continued on to the south it approached the Loyalty Islands which lie east of New Caledonia, passing very near Mare Island around 21/0000 UTC. After passing New Caledonia the cyclone began to accelerate to the southeast and weaken as it came under increasing vertical shear. Warning responsibility was passed to Wellington after 1800 UTC, but Dani was declared extratropical by 22/0500 UTC. JTWC issued its final warning about this time, noting that the center was completely exposed (although well-defined) with the deep convection located 70 nm to the northeast. The extratropical remnants of Dani continued on to the southeast, passing about 425 nm east of Norfolk Island around 2300 UTC on 22 Jan; then turning more to the south, being last mentioned at 24/1100 UTC when located roughly 300 nm east of New Zealand's North Cape. Steve Ready of the New Zealand Meteorological Service has passed along some preliminary damage and casualty information he'd received from Henry Taiki, the Director of the Vanuatu Meteorological Service. A special thanks to Steve for sending me the information. There were two deaths reported due to Tropical Cyclone Dani: one on Ambae Island and one on Malekula. Bauefield Airport at Port Vila (on Efate Island) recorded 545 mm in 24 hrs, including 312.4 mm between 0000 UTC and 0600 UTC on 20 Jan--the average January rainfall for Bauefield is 457 mm. Hurricane force winds were experienced on Espiritu Santo and Malekula and some nearby islands. Roads were badly damaged, and one bridge was washed 200 to 300 metres from its location. Many houses of lighter construction, plus some traditional homes, were destroyed. River flooding was the major problem on Efate with 12 homes destroyed in Vila by the La Colle river. Agricultural crops affected included sweet potatoes, yams, tapioca, kava, and coconut. Tropical Cyclone Olinda (TC-09F / TC-13P) 19 - 24 January ------------------------------------------ Tropical Cyclone Olinda formed in the eastern portion of the Australian Region and was named by the Brisbane TCWC at 1800 UTC on 21 Jan when just west of the Fiji AOR. For the early history of this cyclone see the section of this summary covering the Australian Region. Olinda entered the Southwest Pacific basin shortly after being named by Brisbane at a point about 400 nm west-northwest of Noumea. The cyclone had MSW estimated at 45 kts and was already moving at a fairly good pace toward the east-southeast. Olinda was approaching an area of westerly shear and slightly cooler SSTs, but the steering flow was an increasing deep-layer mean flow; and with environmental factors being basically favorable for further intensification, the cyclone continued to strengthen. Peak intensity of 55 kts was reached after Olinda had passed into the Wellington AOR on 23 Jan. While in Nadi's AOR Olinda did not directly threaten any populated areas. The cyclone remained on a relatively steady east-southeasterly trajectory which carried it about 150 nm southwest of New Caledonia. Olinda passed about 150 nm south of Noumea at 23/0000 UTC just as it was about to cross 25S into Wellington's AOR. The storm subsequently turned to more of an easterly course and, as vertical shear increased, began to lose tropical characteristics. The Wellington office deemed Olinda extratropical at 1800 UTC on 23 Jan as it sped eastward, and was last mentioned 24 hours later when the remnants were located about 525 nm south of Fiji. Tropical Cyclone Pete (TC-10F / TC-14P) 20 - 27 January ---------------------------------------- Tropical Cyclone Pete formed in the Australian Region and was named by the Brisbane TCWC at 1200 UTC on 22 Jan when it was centered about 400 nm east of Cairns, Queensland. For a discussion of the earlier history of this cyclone, see the section of this summary covering the Australian Region. Pete entered Fiji's AOR at around 1800 UTC on 23 Jan at a point only about 90 nm to the south of where Tropical Cyclone Olinda had crossed 160E forty-eight hours earlier. Pete entered the Southwest Pacific basin at its peak intensity of 50 kts MSW and, like Olinda, moved at a fairly quick pace towards the southeast under a northwesterly steering current. The cyclone was being subjected to strengthening westerly shear at this stage and was also racing into waters already cooled somewhat by the passage of Olinda and Dani. At 24/0600 UTC it started to turn east-southeast and six hours later was located near the boundary with Wellington's AOR (25S). Warning responsibility was handed over to Wellington in anticipation of Pete's continued east-southeastward motion, but by 25/0000 UTC it was clearly evident on visible satellite pictures that the center was back north of 25S. Therefore, Nadi resumed issuing warnings as Pete headed east. However, the environmental conditions had become quite unfavorable and Pete steadily weakened. By late on the 25th the low-level center was exposed and there was no deep convection. The cyclone had just crossed the path where Tropical Cyclone Olinda had passed about two and a half days earlier, and was forecast to reach Tropical Cyclone Dani's five day-old path by 26/1200 UTC. Pete passed about 100 nm south of Noumea around 1200 UTC on 25 Jan and continued drifting slowly eastward as it weakened. The system was downgraded to a depression at 26/0600 UTC but some gales continued in the southern and eastern quadrants for another day or so. The last warning at 27/1800 UTC placed the center about 200 nm southeast of Noumea. Tropical Cyclone Pete did not approach any populated land areas during its lifetime. Non-developing South Pacific Disturbances ----------------------------------------- There were several tropical disturbances or weak depressions in the Fiji AOR which were given sequence numbers but for which warnings were not issued. TD-04F actually occurred in December, forming in the Coral Sea in Brisbane's AOR on 25 Dec but moving southeast across 160E. This system formed and remained in a strongly sheared environment and by 26 Dec had dissipated. TD-05F formed on 1 Jan just north of the Southern Cooks and moved slowly west-northwestward. Initially this system had some baroclinic characteristics but later developed a fair amount of convection. The depression was strongly affected by diurnal effects, and by 3 Jan convection near the center had begun to decrease as it came under southerly shear. The system had become unclassifiable by 5 Jan. TD-06F was a small disturbance which formed on 3 Jan to the southwest of French Polynesia. This system formed in an environment of strong shear as it drifted slowly southwest, and never showed any significant degree of organization. The most significant non-developing disturbance was TD-08F which formed on 16 Jan in an active convergence zone located just to the east of Fiji. There were also other minor eddies along the convergence line which was moving towards Fiji. From early on the 17th through the 19th this convergence zone with embedded eddies moved across Fiji causing the worst flooding event in this century, especially in the Northern and Western (administrative) Divisions. The death toll was 6, and damage to property, infrastructure, and crops reached $4 million in Fijian dollars. A station in the western part of Viti Levu recorded 396 mm of rainfall in 24 hrs, which was a record for a non-cyclone induced rain event. After passing Fiji convective organization about the center increased some, but vertical shear inhibited any significant strengthening. By the 19th the disturbance had drifted to the southwest of Fiji into much cooler waters and stronger northwest shear which led to its demise. *********************************************************************** 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 included in the July summary. I will include this glossary from time to time, primarily in "lean" months without a lot of tropical cyclone activity to cover. But if anyone missed receiving it and wishes to obtain a copy, send me an e-mail privately and I'll forward 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 in the following manner: (a) FTP to: hrd-type42.nhc.noaa.gov [140.90.176.206] (b) Login as: anonymous (c) For a password use your e-mail address (d) Go to "data" subdirectory (Type: cd data) (e) Set file type to ASCII (Type: ascii) (f) Transfer file (Type: get remote_file_name local_file_name ) (The files will be named with an obvious nomenclature--using January as an example: jan99.tracks) (g) To exit FTP, type: quit Both the summaries and the track files are standard text files created in DOS editor. Download to disk and use a viewer such as Notepad or DOS editor to view the files. The first summary in this series covered the month of October, 1997. If anyone wishes to retrieve any of the previous summaries, they may be downloaded from the aforementioned FTP site at HRD. The summary files are catalogued with the nomenclature: jan99.sum, for example. Back issues can also be obtained from the following websites (courtesy of Michael Bath, Michael V. Padua, Tom Berg, and Michael Pitt): 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: Prepared by: Gary Padgett E-mail: garyp@alaweb.com Phone: 334-222-5327 (nights & weekends) / 850-882-2594 (weekdays) *********************************************************************** ***********************************************************************