MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY APRIL, 2006 (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.) ************************************************************************* APRIL HIGHLIGHTS --> Late season Northern Australian storm becomes one of the Southern Hemisphere's most intense cyclones on record--fortunately makes landfall in sparsely populated area --> Intense Bay of Bengal cyclone makes destructive strike in Myanmar ************************************************************************* ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for April: No tropical cyclones ************************************************************************* NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180 Activity for April: No tropical cyclones ************************************************************************* NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180 Activity for April: No tropical cyclones ************************************************************************* NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for April: 1 very severe cyclonic storm Sources of Information ---------------------- Most of the information presented below is based upon tropical cyclone warnings and significant tropical weather outlooks issued by the Joint Typhoon Warning Center of the U. S. Air Force and Navy (JTWC), located at Pearl Harbor, Hawaii. Occasionally some information may be gleaned from the daily tropical weather outlooks and other bulletins issued by the Indian Meteorological Department (IMD), which is the World Meteorological Organization's Regional Specialised Meteorological Centre (RSMC) for the basin. The reported maximum sustained winds (MSW) are based on a 1-minute averaging period, which is used by all U. S. civilian and military weather services for tropical cyclone warnings. For synoptic observations in the North Indian Ocean region, both 10-minute and 3-minute average winds are employed, but IMD makes no attempt to modify the Dvorak scale for estimating tropical cyclone intensity; hence, a 1-minute average MSW is implied. In the North Indian Ocean basin JTWC usually does not initiate warnings until a system has become well-organized and likely to attain tropical storm status within 48 hours. VERY SEVERE CYCLONIC STORM MALA (TC-02B / BOB0601) 24 - 29 April --------------------------------------------------- Mala: contributed by Sri Lanka A. Introduction --------------- When JTWC numbers an April system in the Bay of Bengal as Tropical Cyclone 02B--watch out! Dating back to 1981, there have been only two April tropical cyclones in the North Indian Ocean, and both (in 1991 and 1994) were (1) numbered as TC-02B, (2) became very intense tropical cyclones, and (3) made destructive strikes on the Asian mainland. And this month's Cyclonic Storm Mala qualified in all three categories. It was numbered as Tropical Cyclone 02B per JTWC (BOB0601 per IMD's nomen- clature), became an intense cyclone, and made a destructive strike on the mainland, in this case in Myanmar (formerly Burma). This is as good a place as any to announce a change in the focus of the monthly summaries. My time is extremely limited, and what time I do have is often quite fragmented due to various commitments and the time required to help care for my elderly mother. If the tropical cyclone summaries are to continue, some time-reduction techniques are necessary. Last year I discovered the online encyclopedia, Wikipedia, and the storm reports which were being written and archived there. In fact, I included links to the Wikipedia reports for Hurricanes Dennis and Emily last year and perhaps for some others. Based on the fact that reports for Atlantic hurricane seasons dating back into the 1950s have been archived on Wikipedia, I perceive that the summaries will be available there long-term. Some of the Wikipedia reports are rather brief, and in some cases (such as TCs Elia and Hubert following), I will write a more detailed summary. But when the Wikipedia report is rather detailed (such as for Mala and most of the Atlantic storms), I will for the most part just reference the online report and include some supplemental information. Since the May and June summaries will be rather brief due to few TCs worldwide, I will explain there a little more fully how I plan to structure the summaries in the future. B. Links and Comments --------------------- The online Wikipedia report may be accessed at the following URL: However, be advised that some of the links referenced in the report were temporary and no longer work. This report gives a fairly detailed overview of Mala. One minor correction should be pointed out. As I understand things, IMD does not issue a BOB number (or ARB number for Arabian Sea systems) until a system has reached cyclonic storm (i.e., tropical storm) status. The online report states that IMD designated it as BOB0601 when the deep depression stage (30 kts) was reached. JTWC's first warning on Tropical Cyclone 02B was issued at 24/1800 UTC when the system was located approximately 600 nm southwest of Yangon (formerly Rangoon), Myanmar. Regarding the intensity of Mala, JTWC's peak estimated MSW for the cyclone was 115 kts in the warnings issued at 28/0600 and 28/1800 UTC. There was no warning issued at the peak intensity time of 28/1200 UTC. However, both JTWC and AFWA assigned Dvorak ratings of T6.5/6.5 at that hour, so it seems likely that Mala reached a peak intensity of 125 kts about that time while located approximately 200 nm west-southwest of Yangon. Based on the JTWC warnings, the cyclone's intensity had dropped to about 100 kts by the time of landfall near Gwa, Myanmar. The final warning from JTWC, issued at 29/1800 UTC, placed the weakening 35-kt center inland about 370 km north-northeast of Yangon. A graphic depicting the track of Cyclonic Storm Mala may be found at the following link: C. Damage and Casualties ------------------------ According to the Wikipedia report, there were 22 deaths reported in Myanmar with 6000 houses damaged and 351 completely destroyed. More detailed information may be found in the online report. D. The 1991 and 1994 April Cyclones ----------------------------------- Since I mentioned the previous destructive April tropical cyclones in the Bay of Bengal numbered TC-02B, I thought I'd include a little information on them. The 1991 cyclone was one of the strongest storms on record in the North Indian Ocean--the JTWC Best Track file assigns it a peak MSW of 140 kts with an estimated CP of 898 mb. This deadly cyclone struck Bangladesh with a lost of 139,000 lives, according to the publication The World Almanac and Book of Facts. A track of Tropical Cyclone 02B of 1991 may be accessed at the following URL: For information on the 1994 cylcone, I have turned to Jack Beven's Weekly Tropical Cyclone Summaries, which of course were the predecessor of the current monthly summaries. Jack began writing his weekly reports in July, 1991, so missed covering the deadly Bay of Bengal storm of that year by a few months. However, he did include a fair amount of information on the 1994 cyclone. Tropical Cyclone 02B of 1994 hit the coastline of Bangladesh near Cox's Bazaar with a peak MSW estimated at 135 kts. (The JTWC Best Track gives a peak intensity of 125 kts for this cyclone, so it appears likely the intensity was adjusted downward a bit in post-analysis.) This storm was responsible for 139 deaths in Bangladesh with more than 5000 persons injured. Also, at the time of Jack's report, 300 Thai fishermen, whose boats were wrecked by the cyclone, were still missing. A track of Tropical Cyclone 02B of 1994 may be accessed at the following URL: (Report written by Gary Padgett) ************************************************************************* SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E Activity for April: 1 moderate tropical storm 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 Tropical Cyclone Advisory Centres in Mauritius and Madagascar with longitude 55E being the demarcation line between their respective areas of naming 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. TROPICAL STORM ELIA (MFR-13 / TC-22S) 6 - 16 April --------------------------------------- Elia: contributed by Madagascar The origin of the tenacious Elia lay with an area of persistent convection first noted approximately 830 nm east of Diego Garcia at 1800 UTC on 5 April. Vertical wind shear was low to moderate and upper-level outflow was weak. MFR initiated advisories on the system as Tropical Disturbance 13 at 0000 UTC 6 April, placing a weak 20-kt center roughly 650 nm west-northwest of the Cocos Islands. The LOW drifted westward but remained weak and advisories were discontinued at 07/0000 UTC. A JTWC satellite bulletin at 08/0600 UTC fixed a center several hundred miles to the east, or approximately 425 nm west-northwest of the Cocos Islands and within BoM Perth's area of warning responsibility. It seems more likely that this was a new center forming within the larger area of disturbed weather. JTWC assessed the potential for development as 'fair' as the system moved farther to the east, reaching a point about 200 nm north-northwest of the Cocos Islands by 1200 UTC on the 9th. Deep convection was confined to the western semicircle and conditions were only marginally favorable for further strengthening. Over the next couple of days the LOW wandered erratically on a generally southerly track, thence curving back to the west and passing about 100 nm northwest of the Cocos Islands. The system appeared somewhat better organized on the 11th with JTWC's satellite estimates suggesting that it was near tropical storm intensity. Perth initiated shipping bulletins on the LOW at 11/1800 UTC with the center located approximately 325 nm west-northwest of the Cocos Islands, and JTWC followed with their first warning on TC-22S at 12/1200 UTC. The system was then located about 400 nm west of the Cocos Islands and was moving southwestward at 10 kts. Significant strengthening was not expected as the system was forecast to remain in an unfavorable vertical shear environment. TC-22S re-entered MFR's area of warning responsibility at 0000 UTC on 13 April and was classified as a 30-kt tropical depression. At 13/1200 UTC the depression was upgraded to a tropical storm and assigned the name Elia by the Meteorological Services of Mauritius. The south- westerly motion continued and Elia reached its peak intensity of 45 kts at 14/0600 UTC while centered roughly 550 nm west-southwest of the Cocos Islands. (JTWC's estimated peak 1-min avg MSW was 55 kts.) Vertical shear had not lessened, but Elia's poleward outflow had increased significantly. By the 15th the LLCC was becoming decoupled from the convection and the tropical storm accordingly began to weaken in a high shear environment. JTWC issued their final warning at 15/1200 UTC, and MFR downgraded Elia to a tropical disturbance at 16/0600 UTC. Six hours later that agency issued the final advisory on ex-Elia, placing the center approximately 870 nm southeast of Diego Garcia. A graphic depicting the track of Tropical Storm Elia may be found at the following link: A brief report with a satellite picture of Elia may be accessed at the following URL: No damage or casualties are known to have resulted from Tropical Storm Elia. (Report written by Gary Padgett) ************************************************************************* NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E Activity for April: 1 tropical cyclone 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 April ------------------------------------------ Two tropical cyclones traversed Southern Hemisphere waters between 135E and 90E during the month of April. The first one, Tropical Cyclone Hubert, formed to the north of Western Australia early in the month and moved generally southward toward the coastline, but encountered strong vertical shear and weakened dramatically upon approaching the coast. A short report on Hubert follows. The other, and much more significant cyclone, was a visitor from east of 135E. Tropical Cyclone Monica, which had formed in the Coral Sea, moved westward across the Cape York Peninsula into the Gulf of Carpentaria where it deepened into one of the most intense tropical cyclones ever noted in the Southern Hemisphere. Following a track remarkably similar to intense Tropical Cyclone Ingrid in March, 2005, Monica swung west-northwestward in the Gulf, clearing the northeastern tip of the Northern Territory before resuming a westerly track. However, Monica did not go as far west as Ingrid had moved and suddenly swung to the southwest and inland about 15 nm west of Maningrida on 24 April. The peak MSW (10-min avg) of 135 kts assigned by BoM Darwin is among the highest, if not the highest, ever assigned operationally by an Australian TCWC. An excellent report on Monica, written by Simon Clarke, follows in the next section of this summary covering the Northeast Australia/ Coral Sea region. TROPICAL CYCLONE HUBERT (TC-21S) 4 - 7 April ------------------------------------------- A. Storm History ---------------- The daily Tropical Weather Outlook issued by the Perth TCWC on 1 April mentioned a weak tropical LOW near 14.0S/115.0E, but the system was not forecast to develop into a tropical cyclone over the next three days. JTWC first mentioned the disturbance in the STWO issued at 02/1800 UTC, noting that deep convection was cycling near a broad but symmetric LLCC. Vertical shear was low to moderate and the LOW was situated under the western extent of a 200-mb anticyclone. By the next day the system's chances for development were looking better, and BoM Perth initiated gale warnings for shipping interests at 0300 UTC on 4 April, placing the center approximately 475 nm north of Onslow, Western Australia. The system's organization continued to improve and JTWC issued a TCFA at 2100 UTC. Shear was low to moderate and outflow was good and improving. BoM Perth upgraded the LOW to Tropical Cyclone Hubert at 1200 UTC on 5 April, placing the center about 300 nm north-northeast of Onslow. The cyclone, which had initially moved southeastward during its developmental stages, commenced on a south-southwesterly trajectory as it was steered by a mid-level ridge over Western Australia. Hubert was expected to follow a more southwesterly track, but a weak upper-level LOW to the south of the cyclone did not fill as anticipated. This created a weakness in the ridge, allowing Hubert to move on a more southerly track toward the Western Australian coastline. Hubert gradually intensified, reaching a peak intensity of 55 kts at 07/0000 UTC while centered approximately 115 nm north of Onslow. (JTWC had upped the 1-min avg MSW to 55 kts as early as 1800 UTC on the 5th, but noted that the LLCC remained partially-exposed due to moderate northeasterly shear.) Shortly after peaking in intensity, Hubert made a slight jog to the south-southeast toward the coastline. However, the cyclone ran into atmospheric hostilities in the form of high vertical shear and quickly began to weaken. The final advice from BoM Perth at 07/1500 UTC downgraded Hubert to a tropical LOW and placed the center near the coast about 20 nm east-northeast of Onslow and about 30 nm southwest of Mardie. The system subsequently moved inland and dissipated. A graphic depicting the track of Tropical Cyclone Hubert may be found at the following link: The track of Hubert in tabular format may be accessed at the following link: A brief report on Hubert with a satellite image of the system may be accessed at the following URL: B. Meteorological Observations ------------------------------ Following are a few synoptic observations sent to the author by Matthew Saxby. A special thanks to Matthew for sending the information. (1) Wind -------- At Karratha sustained winds (10-min avg) fell just shy of gale force, reaching ESE 33 kts at 06/0130 UTC but remaining near 30 kts for over 24 hours. The peak gust of 45 kts was recorded at 06/0830 UTC. The weather station on Bedout Island recorded a maximum 10-min avg wind of NE 38 kts at 06/1900 UTC. At Barrow Island winds first exceeded gale force at 06/1230 UTC and did so continuously through 07/0500 UTC. Peak sustained winds of 41 kts were observed at 06/2130 UTC, 07/0400 UTC and 07/0500 UTC from the ESE, ENE and NE, respectively. A peak gust of 51 kts was recorded several times between 06/1631 UTC and 07/0100 UTC. (2) Rainfall ------------ In the 24 hours ending at 0100 UTC on 7 April, Barrow Island recorded 234 mm of rain. In the 24 hours ending at 08/0100 UTC, Coolawanyah recorded 156 mm and Mt. Florance measured 132 mm. D. Damage and Casualties ------------------------ No reports of damage or casualties resulting from Tropical Cyclone Hubert have been received. (Report written by Gary Padgett) ************************************************************************* NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E Activity for April: 1 over land tropical LOW 1 severe tropical cyclone 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 April ----------------------------- Following a track very similar to the intense Tropical Cyclone Ingrid of March, 2005, Severe Tropical Cyclone Monica became one of the most intense tropical cyclones ever tracked in the Southern Hemisphere since the commencement of the satellite era. The cyclone was one of the latest on record to affect the Northern Territory and brought very heavy rainfall to the region. Until Monica came along it was beginning to look like this would be the first season since the 1988-89 season that the Darwin TCWC would not see a named tropical cyclone anywhere within their AOR. According to information from Mark Kersemakers, a forecaster at BoM Darwin, the 1987-88 season was also stormless in Darwin’s AOR. An outstanding report on Monica, authored by Simon Clarke, follows. Also worthy of mention was a tropical LOW which meandered about over the Northern Territory and adjacent Gulf of Carpentaria waters for almost two weeks during the first part of April. While fairly well-organized, this LOW was not nearly as significant as the one in late January which brought sustained winds to near gale force with gusts to storm force in some areas. It did, however, enhance monsoonal rainfall which caused floods in the Katherine area, leading to large-scale evacuations of people living in the area. Some information on these floods may be found at the following link: SEVERE TROPICAL CYCLONE MONICA (TC-23P) 16 - 26 April 2006 -------------------------------------------------- A. Introduction --------------- The Southern Hemisphere TC season kept its best for last. TC Monica was not only the strongest cyclone of the season in the Southern Hemisphere; but also one of the Southern Hemisphere’s strongest in recorded history. While not causing as much destruction as TC Larry from a month earlier, Monica is noted for bringing tremendous rainfall across the north tropical coast of Queensland, Cape York Peninsula and the Top End of the Northern Territory. A brief preliminary report on Severe Tropical Cyclone Monica, authored by the Australian Bureau of Meteorology is also available on-line at the following URL: An unofficial summary can also be found at the following URL which also includes some impressive satellite imagery: Also of particular note about Monica is that the cyclone arrived quite late in the season which is usually over in the last weeks of April in the Southern Hemisphere. B. Storm History ---------------- Monica developed from a cluster of tropical thunderstorms that was identified as early as 15 April in the Solomon Sea. Under an upper- level ridge over the northern Coral Sea, the consolidating area of convection gradually developed a LLCC near 9.0S/152.5E. Development continued in a favourable environment consisting of low vertical wind shear, good divergence aloft and high SSTs. On 16 April, the LOW rounded the SE tip of Papua New Guinea and entered the northern Coral Sea, moving SW at approx. 8 kts. At 17/0000 UTC the developing 995-hPa LOW was located at 12.4S/150.0E (approx. 330 nm NE of Cooktown, Queensland) and was officially named Monica. The advisories issued by BoM Queensland indicated that Monica was expected to intensify and move on a general westward path toward Cape York Peninsula due to the steering influence of the low to mid-level ridge to the south. Monica followed this forecast track and by 18/1200 UTC reached hurricane status (65-kt winds 10-min avg) approximately 125 nm E of Lockhart River (13.0S/145.6E) while accelerating to 12 kts on a general W to WSW path toward Cape York. At 19/0600 UTC, Monica made its first landfall as a 960-hPa, max 10-min avg 80-kt cyclone approx. 20 nm S of Lockhart River (13.1S/ 143.3E). Just prior to landfall, Monica slowed slightly with the eye appearing to loop south and then parallel to the coast for a while prior to making landfall. Interestingly, Monica crossed the coast in almost the exact same point as Ingrid from the previous 2004/05 season (see unofficial comparison at Link 4). Comparisons between Monica and Ingrid were not to finish there. Monica moved quite quickly westwards across Cape York Peninsula and despite a substantial breakdown in core convection and fragmented radial outflow, emerged as a Category 2 cyclone in the Gulf of Carpentaria 20 nm S of Aurukun (13.6S/141.5E) at 20/0000 UTC. Like Ingrid from the season before, Monica embarked on a general NW path across the very warm Gulf waters in response to a subtropical ridge anchored to the SW of the system and steadily intensified as the surface inflow around the LLCC improved. Hurricane intensity was regained at 20/1800 UTC near 13.6S/140.2E (220 nm ESE of Nhulunbuy, Northern Territory and 90 nm W of Aurukun, Queensland) as the cyclone continued to drift to the NW at 4 kts. Monica continued to intensify under highly favourable conditions of high SSTs and weak vertical wind shear. The cyclone developed a regular and circular clear eye as it traveled to the north of the NE tip of the Northern Territory. Category 5 status was achieved at 22/0600 UTC near 12.4S/139.2E (140 nm E of Nhulunbuy) and this was maintained until landfall. The cyclone was tracked by the Nhulunbuy (Gove) radar which showed the classic concentric eye-wall characteristic of intense cyclones. The cyclone continued to improve in structure with very deep convection expanding even further with a very symmetrical warm eye which contracted to 20 nm in diameter surrounded by a ring of cold convective tops. Monica maintained a westerly path at 8 kts approx. 75 nm off the northern coastline, passing over the Wessel Islands. Peak intensity of 905 hPa and max 10-min avg winds of 135 kts was achieved at 23/0600 UTC near 11.4S/137.4E (115 nm ENE of Elcho Island) and maintained for a further 12 hours. Despite being more powerful than Ingrid from the 2004/05 season, it is noted that Monica’s path was slightly farther north, keeping its relatively larger, intense circulation offshore as the storm tracked westward parallel to the Top End. (Also of note, the Joint Typhoon Warning Agency pegged Monica at a peak of 155 kts with gusts to 190 kts, which is equivalent to a moderate American Category 5 cyclone (Saffir/Simpson Scale). CIMSS estimates at the time also placed Monica as a 170-kt/T8.0/868.5-mb cyclone, which certainly would rank Monica in the top echelon of cyclones in recorded history worldwide. It should be noted that reliable records of cyclone intensity only go back to the mid-1980s in the Southern Hemisphere.) Finally the cyclone shifted to an 8-kt WSW track in response to a weakening of the mid-level ridge to the south as a consequence of an approaching major shortwave trough over Western Australia. This brought the centre of Monica across the coastline near 11.8S/134.1E (about 15 nm W of Maningrida or 190 nm ENE of Darwin) just prior to 24/1200 UTC as a 915-hPa cyclone. The very destructive core of Monica with gusts to 350 km/hr (190 kts) affected the coast between Maningrida and Goulburn Island while crossing the coast. However, Monica weakened very rapidly over land, losing hurricane intensity in a little under 12 hours and cyclone status overland near Darwin (12.6S/131.4E) at 25/0000 UTC as the cyclone lost all of its cold convective cloud tops. The LLCC remained evident to 400 hPa in Darwin vertical wind profiler data and the depression moved WNW and then SSW into the Timor Sea. However, the remnant LOW remained too close to the NT coastline for any significant re- intensification with all deep convection developing over land well away from the centre. The exposed LLCC moved inland over the SW Top End east of Port Keats and dissipated soon afterwards. C. Observations --------------- No meteorological instruments recorded the full impact of Monica. However, the following brief notes were available at the time of report writing. In Queensland, peak wind gusts recorded were 59 kts at 15:00 local time (19/0400 UTC) at Lockhart River and 50 kts at 7:43pm local time (19/0943 UTC) inland at Coen. The heaviest rain occurred well south of the cyclone within the strong onshore flow in the area between Cape Tribulation and Cairns. A number of places around the Cairns region received more than 200 mm as the cyclone made its way across Cape York Peninsula. On 20 April, Copperlode Dam (11 km W of Cairns) recorded 340 mm in the 24 hours to 9 am and Cairns itself passed its monthly April rainfall record of 550 mm. In the Northern Territory, Gove Airport recorded a gust of 44 kts as Monica passed well to the north. This observation is the station’s highest April wind in 21 years. Elsewhere the highest wind gusts recorded were 55 kts at Milingimbi at 12:30 local time (24/0330 UTC), 80 kts at Maningrida at 18:31 local time (24/0931 UTC), and 52 kts at Warruwi at 22:00 local time (24/1300 UTC). It is noted that the Maningrida wind gauge became inoperative at 20:02 local time (24/1102 UTC). The BoM reported very heavy rainfall in parts of the western Arnhem district on 23 and 24 April, in the Darwin-Daly district on 25 April and in the Victoria River District on 26 April. The highest 24-hour totals included Ngayawili 190 mm on 24 April; Adelaide River East 225 mm, Elizabeth Valley 192 mm, Noonamah 186 mm, Darwin River Ridge 174 mm, Humpty Doo 166 mm and Channel Island 153 mm on 25 April; and Kidman Springs 261 mm, Coolibah 216 mm and Dashwood Crossing 129 mm on 26 April. A graphic displaying the track of Severe Tropical Cyclone Monica may be found at the following link: D. Preliminary Damage Reports ----------------------------- Monica was a relatively compact cyclone. Similar to Ingrid from the previous season, communities beyond a 50-nm radius of the track were hardly affected by the cyclone’s winds. However, in contrast to Ingrid, Monica brought some of the heaviest rains ever recorded for April through parts of Northern Queensland and the Northern Territory. The following is a preliminary snapshot of the effects of Monica on communities in the cyclone's path, collated from various sources: (1) Northern Queensland ----------------------- There were no immediate reports of injuries or damage, though rain from Monica caused the worst floods in living memory in parts of far north Queensland. Significantly, flooding isolated many parts of the Cape, making it difficult to initially assess the damage. The Lockhart River township (pop. 700) escaped serious harm, although news reports say about 15% of the buildings were damaged. Many roads were cut to traffic including extensive wash outs from major flooding along the Peninsula Developmental Road. Several residents from a Cape York Peninsula aboriginal community and at least three families from cattle properties were airlifted to drier ground due to flooding. Farther south in Cairns several air flights in and out were cancelled on 19 April. All tourist trips to the Great Barrier Reef were also abandoned. The Kuranda Railway, a popular tourist train which winds through World Heritage protected tropical rain forest near Cairns was also halted because of a landslide along the line. As tropical cyclone Monica tracked west across the Gulf of Carpentaria, many of the 75 prawn trawlers that fish the remote off- shore regions took shelter in calmer waters to the south near Karumba and the Northern Territory-Queensland border. The interruption to the banana prawn harvest created at least one week of disrupted fishing time and wasted fuel in less than ideal fishing grounds. One of the largest companies, NewFishing Australia, estimated the disruption will cost them tens of thousands of dollars alone. (2) Top End, Northern Territory ------------------------------- Monica was the strongest cyclone on record to affect the Northern Territory. Destructive winds caused extensive defoliation and felling of trees on Marchinbar Island as the cyclone passed directly over the Wessel Island group. Just north of the island chain, Martjanba outstation was completely destroyed. At Junction Bay, Monica ripped mangrove forests from the ground and destroyed sand dunes. Monica ran over a fairly sparsely populated section of coastline. However, several small aboriginal communities were in the cyclone’s path. A 50-km wide swath of defoliation and major tree damage was reported to the west of Maningrida (pop. 2600) that extended inland over parts of the Kakadu National Park to the escarpment near Oenpelli. Jabiru and Maningrida were spared a direct hit by only a matter of miles. In the Maningrida community, several houses and a local school were reported as being unroofed or extensively damaged. Houses were also damaged and power was lost in other small communities including Milingimbi, Oenpelli, Jabiru and Ngayawili (Elcho Island). Power lines were also damaged in Yirrkala, Ramingining, Warruwi (Goulburn Island) and other smaller communities and outstations. The following URL provides more detail on the recovery operations underway in these communities: Grave fears were held that Monica might reach Darwin as a strong Category 3 cyclone and some domestic and international flights in and out of the city were cancelled as a consequence. The city’s ANZAC Day rites had to be called off. However, Monica weakened dramatically on its overland approach to Darwin and will be remembered there more so for the tremendous late season rain that it bought rather than for its wind damage. The heavy rains cut many roads including the Arnhem Highway at the Adelaide River and Cox Peninsula Road at Berry Creek. Fortunately, no casualties or serious injuries were reported as a consequence of Monica. E. Links -------- Link 1: ======= Satellite imagery – Monica developing in the North West Coral Sea Link 2: ======= Satellite Imagery – Monica crosses Cape York Link 3: ======= A selection of impressive satellite and radar images as Monica passes close to the Top End, Northern Territory: Link 4: ======= Tidal Effects Environmental Protection Agency’s Comparison to Ingrid (Cape York Crossing): (Report written by Simon Clarke) ************************************************************************* SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E Activity for April: 1 tropical depression South Pacific Tropical Activity for April ----------------------------------------- No tropical cyclones formed in the South Pacific basin during the month of April. RSMC Nadi identified one system as a numbered tropical depression, but it was weak. Tropical Depression 17F was first mentioned at 1800 UTC on 20 April, located to the southeast of Fiji and just east of the Dateline. The system was weak with an exposed center and with isolated deep convection located to the south of the LLCC. TD-17F meandered slowly around for a couple of days, but by the 23rd had moved southward out of the tropics and was dropped from the Fiji Tropical Disturbance Summaries. No track was included for Tropical Depression 17F in the accompanying cyclone tracks file. Also, during the final days of April several more LOWs were referenced simply as 'depressions' in the Fiji summaries. These systems were well east of the Dateline and were never classified as 'tropical’ depressions, so it is assumed they were likely hybrid or subtropical in character. ************************************************************************* SPECIAL FEATURE - SOURCES OF TROPICAL CYCLONE INFORMATION The purpose of this section is to list some websites where many and varied types of tropical cyclone information are archived. Many readers will know about these already, but for the benefit of those who don't, I wanted to include them. (1) Aircraft Reconnaissance Information --------------------------------------- Various types of messages from reconnaissance aircraft may be retrieved from the following FTP site: Information regarding how to interpret the coded reconnaissance messages may be found at the following URL: Links are also included to websites with further information about the U. S. Air Force 53rd Weather Reconnaissance Squadron and the NOAA Air- craft Operations Center. (2) Archived Advisories ----------------------- All the advisory products (public advisories, forecast/advisories, strike probabilities, discussions, various graphics) issued by TPC/NHC are archived on TPC's website. For the current year (using 2004 as an example), the archived products can be found at: Links to tropical products archives for earlier years are available at the following URL: JTWC warnings for past storms are archived on the NRL Monterry website: On the NRL site, the link to past years can be found in the upper left corner of the screen. I am not aware at the moment of any other TCWC which archives all its tropical cyclone warning/advisory products for public access, but if I learn of any, I will add them to this list. (3) Satellite Imagery --------------------- Satellite images of tropical cyclones in various sensor bands are available on the NRL Monterrey and University of Wisconsin websites, courtesy of Jeff Hawkins and Chris Velden and their associates. The links are: On the NRL site, the link to past years can be found in the upper left corner of the screen. For the CIMSS site, a link to data archives is located in the lower left portion of the screen. Additional tropical satellite imagery, along with looping ability for composite microwave imagery for the Western Hemisphere north of the equator, can be found at: (1) For the Eastern North Pacific: (2) For the Atlantic, Gulf of Mexico and Caribbean Sea: I'm sure there are other sites with available imagery available, and as I learn of them, I will add the links to this list. ************************************************************************* 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 August, 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, Chris Landsea, and John Diebolt): 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: TROPICAL CYCLONE REPORTS AVAILABLE JTWC now has available on its website the Annual Tropical Cyclone Report (ATCR) for 2004 (2003-2004 season for the Southern Hemisphere). ATCRs for earlier years are available also. The URL is: Also, TPC/NHC has available on its webpage nice "technicolor" tracking charts for the 2005 Atlantic and Eastern North Pacific tropical cyclones; also, storm reports for all the 2005 Atlantic and Eastern North Pacific cyclones are now available, as well as track charts and reports on storms from earlier years. The URL is: 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: garyp@alaweb.com Phone: 334-222-5327 Kevin Boyle (Eastern Atlantic, Western Northwest Pacific, South China Sea) E-mail: newchapelobservatory@btinternet.com Simon Clarke (Northeast Australia/Coral Sea, South Pacific) E-mail: saclarke@iprimus.com.au ************************************************************************* ************************************************************************* Posted: 08.18.06 / Typhoon2000.ph, Typhoon2000.com