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Monthly Global Tropical Cyclone Summary December 2005 [Summaries and Track Data] [Prepared by Gary Padgett] |
MONTHLY GLOBAL TROPICAL CYCLONE SUMMARY DECEMBER, 2005 (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.) ************************************************************************* DECEMBER HIGHLIGHTS --> Rare December hurricane roams Atlantic waters for 5 days --> Atlantic's 27 named storm forms late in month and continues into January --> Two cyclonic storms form in Bay of Bengal ************************************************************************* ********** EXTRA FEATURE ********** A REVIEW OF THE 2005 TROPICAL CYCLONE SEASON FOR THE NORTHERN HEMISPHERE Following is a tabular summary of all the tropical depressions, tropical storms, hurricanes, and typhoons which occurred in the Northern Hemisphere between 1 January and 31 December 2005, as reported in the Monthly Global Tropical Cyclone Summaries prepared by the author. (1) Number - this is the sequential cyclone number assigned by either TPC/NHC, CPHC in Honolulu, or JTWC. If neither of these agencies issued any warnings, no number will be given. (2) Name - the name (if any) assigned by either TPC/NHC, CPHC, IMD, or JMA (and PAGASA for Western North Pacific systems in their area of warning responsibility). (3) Dates - range of dates for which tracking information for the cyclone is available in the Global Tropical Cyclone Tracks files prepared by the author. (4) Pressure - Lowest central pressure (either estimated or recorded) during the lifetime of the cyclone. For Atlantic and Northeastern Pacific systems these will be the values reported in operational advisories from TPC/NHC or CPHC. For Northwest Pacific systems the central pressure estimates are taken from advisories issued by the Japanese Meteorological Agency. An asterisk (*) following the pressure indicates the reading was an actual measured pressure normally obtained by a drop- sonde released during an aerial reconnaissance flight. Central pressure is given in millibars, which is numerically equivalent to hectopascals. (5) MSW - maximum 1-minute average sustained windspeed in knots. For the Northwestern Pacific and North Indian Ocean basins, these will be the highest value assigned operationally by JTWC. For the Atlantic basin the MSW and central pressure values are taken from the official tropical cyclone reports prepared by the TPC/NHC Hurricane Specialists and which are available on TPC/NHC's website: http://www.nhc.noaa.gov> . (6) Basins - tropical cyclone basins where the cyclone tracked during its life: ATL - North Atlantic, Gulf of Mexico, Caribbean Sea NEP - North Pacific east of Longitude 180 NWP - North Pacific west of Longitude 180 (including South China Sea) NIO - Bay of Bengal and Arabian Sea For tropical systems in the NWP basin, two additional columns of information are given: (1) The tropical storm serial number assigned by the Japanese Meteorological Agency to tropical depressions which are deemed to have reached tropical storm intensity. This does not always agree with JTWC's assessment. (2) An estimate of the maximum 10-minute average sustained wind. The value given represents the highest 10-min avg MSW assigned by any agency. If from any warning center other than JMA, a numbered note below identifies which center's value is given. For tropical systems in the NIO basin, an additional column lists the alphanumeric storm identifier assigned by the India Meteorological Department (IMD) for those systems deemed to have reached cyclonic storm (i.e., tropical storm) status by that agency. A number in parentheses (e.g. (1) ) following an entry refers to a note following the entries for the given basin. A separate table is given for each of the four Northern Hemisphere basins. *********************************************************************** ATLANTIC BASIN NUM NAME DATES CENT PRS MSW BASIN (mb) (kts) ------------------------------------------------------------------------ 01 Arlene 08-13 Jun 989 * 60 ATL 02 Bret 28-30 Jun 1002 * 35 ATL 03 Cindy 03-08 Jul 991 * 65 ATL (1) 04 Dennis 05-13 Jul 930 * 130 ATL 05 Emily 11-21 Jul 929 * 140 ATL (2) 06 Franklin 21-31 Jul 997 60 ATL 07 Gert 23-25 Jul 1005 * 40 ATL 08 Harvey 02-12 Aug 994 * 55 ATL 09 Irene 04-18 Aug 970 90 ATL 10 ----- 13-14 Aug 1008 30 ATL 11 Jose 22-23 Aug 998 * 50 ATL (7) 12 Katrina 23-31 Aug 902 * 150 ATL 13 Lee 28 Aug-02 Sep 1006 35 ATL 14 Maria 01-12 Sep 962 100 ATL 15 Nate 05-12 Sep 979 80 ATL 16 Ophelia 06-20 Sep 976 * 75 ATL 17 Philippe 17-24 Sep 985 * 70 ATL 18 Rita 18-26 Sep 895 * 155 ATL (3) 19 ----- 30 Sep-02 Oct 1006 30 ATL 20 Stan 01-05 Oct 977 * 70 ATL 21 Tammy 05-06 Oct 1001 * 45 ATL 22 ----- 08-09 Oct 1008 30 ATL (4) 23 Vince 09-11 Oct 988 65 ATL 24 Wilma 15-26 Oct 882 * 160 ATL (5) 25 Alpha 22-24 Oct 998 45 ATL 26 Beta 27-31 Oct 960 * 100 ATL (8) 27 Gamma 14-21 Nov 1002 * 45 ATL (6) 28 Delta 21-30 Nov 980 60 ATL 29 Epsilon 28 Nov-09 Dec 981 75 ATL 30 Zeta 30 Dec-06 Jan 994 55 ATL NOTES: (1) Operationally, Cindy was treated as a tropical storm. It was upgraded to a hurricane in post-storm analysis. (2) Emily's peak MSW was upped from 135 kts to 140 kts during post-storm analysis, thereby upgrading the storm to Category 5 status. (3) Rita's minimum CP was lowered from 897 mb to 895 mb and peak MSW upped from 150 kts to 155 kts during post-storm analysis. (4) System was classified as a subtropical depression. (5) Wilma's peak MSW was upped from 150 kts to 160 kts during post-storm analysis. The CP of 882 mb is the lowest ever measured in an Atlantic tropical cyclone. (6) Gamma's peak MSW was upped from 40 kts to 45 kts during post-storm analysis. (7) Jose's minimum CP was lowered from 1001 mb to 998 mb and peak MSW upped from 45 kts to 50 kts during post-storm analysis. (8) The official TPC/NHC report on Beta is not yet available online, so the CP and MSW given here represent the operational values. ************************************************************************ NORTHEAST PACFICIC BASIN NUM NAME DATES CENT PRS MSW BASIN (mb) (kts) ------------------------------------------------------------------------ 01E Adrian 17-20 May 982 70 NEP 02E Beatriz 21-24 Jun 1000 45 NEP 03E Calvin 26-29 Jun 1000 45 NEP 04E Dora 04-06 Jul 1006 35 NEP 05E Eugene 18-20 Jul 989 60 NEP 01C ----- 03-05 Aug 1008 25 NEP 06E Fernanda 09-16 Aug 979 75 NEP 07E Greg 11-15 Aug 1000 45 NEP 08E Hilary 19-25 Aug 970 90 NEP 09E Irwin 25-28 Aug 1000 45 NEP 10E Jova 12-25 Sep 960 100 NEP 11E Kenneth 14-30 Sep 948 115 NEP 12E Lidia 17-19 Sep 1003 40 NEP 13E Max 18-22 Sep 987 70 NEP 14E Norma 23-27 Sep 994 55 NEP 15E Otis 28 Sep-03 Oct 970 90 NEP 16E ----- 15-20 Oct 1006 30 NEP ************************************************************************ NORTHWEST PACFICIC BASIN JTWC NAME(S) JMA DATES CENT MSW MSW BASIN NUM TROP STM PRS 1-MIN 10-MIN NUM (mb) (kts) (kts) ------------------------------------------------------------------------ 01W Kulap 0501 13-19 Jan 985 60 50 NWP 02W Roke/Auring 0502 13-19 Mar 980 65 60 NWP (1) --- ----- ---- 18 Apr 1006 -- 30 NWP (2) 03W Sonca/Bising 0503 20-29 Apr 940 115 90 NWP (1) --- Crising ---- 15-18 May 1004 -- 30 NWP 04W Nesat/Dante 0504 30 May-14 Jun 930 125 110 NWP (1) --- Emong ---- 04-07 Jul 1000 -- 30 NWP 05W Haitang/Feria 0505 10-20 Jul 915 140 130 NWP (1) 06W Nalgae 0506 18-25 Jul 992 50 45 NWP 07W Banyan 0507 20-31 Jul 980 60 60 NWP (1) 08W Washi 0508 28-31 Jul 985 45 50 NWP (1) 09W Matsa/Gorio 0509 30 Jul-08 Aug 950 90 90 NWP (1) 10W Sanvu/Huaning 0510 09-14 Aug 985 65 60 NWP (3) --- (NMCC-02) ---- 09-12 Aug 994 -- 30 NWP (1) 11W Mawar 0511 19-29 Aug 930 130 110 NWP (1) 12W Guchol 0512 19-26 Aug 980 60 55 NWP 13W Talim/Isang 0513 26 Aug-02 Sep 925 125 130 NWP (1) --- ----- ---- 27-30 Aug 1000 -- 30 NWP 14W Nabi/Jolina 0514 29 Aug-11 Sep 925 140 120 NWP (1) 15W Khanun/Kiko 0515 05-16 Sep 945 115 100 NWP (1) --- ----- ---- 12-14 Sep 998 -- 30 NWP (4) 16W Vicente 0516 15-19 Sep 985 40 45 NWP 17W Damrey/Labuyo 0518 19-27 Sep 955 90 110 NWP (1) 18W Saola 0517 19-28 Sep 950 100 90 NWP (1) 19W Longwang/Maring 0519 25 Sep-03 Oct 930 130 120 NWP (1) 20W ----- ---- 06-08 Oct 1006 30 30 NWP 21W Kirogi/Nando 0520 09-20 Oct 935 125 100 NWP (1) 22W Kai-tak 0521 25 Oct-02 Nov 950 90 80 NWP 23W Tembin/Ondoy 0522 06-12 Nov 1000 45 45 NWP (5) 24W Bolaven/Pepeng 0523 13-20 Nov 975 75 65 NWP (1) 25W Quedan ---- 16-22 Dec 1000 40 30 NWP NOTES: (1) The highest 10-min avg MSW was assigned by NMCC. (2) Classified as a tropical depression by JMA and CWB of Taiwan only. (3) The highest 10-min avg MSW was assigned by NMCC and HKO. (4) This depression was the predecessor of Cyclonic Storm Pyarr in the North Indian Ocean basin. Only the Thai Meteorological Department tracked the system as a continuous entity from its birth in the South China Sea until its demise inland in India. (5) The highest 10-min avg MSW was assigned by NMCC and PAGASA. ************************************************************************ NORTH INDIAN OCEAN BASIN NUM NAME IMD ID DATES CENT PRS MSW BASIN (mb) (kts) ------------------------------------------------------------------------ 01B ----- ------- 08-10 Jan --- 25 NIO 02B Hibaru BOB0501 13-17 Jan --- 35 NIO --- Pyarr BOB0502 14-21 Sep 998 35 NIO (1) 03B ----- ------- 02-03 Oct --- 35 NIO 04B ----- ------- 26-28 Oct --- 35 NIO --- ----- ------- 20-22 Nov 998 30 NIO 05B Baaz BOB0503 27 Nov-03 Dec 998 45 NIO 06B Fanoos BOB0504 05-12 Dec 984 65 NIO (2) 07B ----- ------- 15-24 Dec 994 50 NIO NOTES: (1) This system's origins lay with a South China Sea depression which existed from 12-14 September. Only the Thai Meteorological Department tracked the system as a continuous entity from its birth in the South China Sea until its demise inland in India. (2) The peak 10-min avg MSW assigned by the Thai Meteorological Department was 65 kts. ************************************************************************* ACTIVITY BY BASINS ATLANTIC (ATL) - North Atlantic Ocean, Caribbean Sea, Gulf of Mexico Activity for December: 1 tropical storm 1 hurricane ** ** - system formed in late November but reached hurricane intensity in early December Sources of Information ---------------------- Most of the information presented below was obtained from the various tropical cyclone products issued by the Tropical Prediction Center/National Hurricane Center (TPC/NHC) in Miami, Florida: discussions, public advisories, forecast/advisories, tropical weather outlooks, special tropical disturbance statements, etc. Some additional information may have been gleaned from the monthly summaries prepared by the hurricane specialists and available on TPC/NHC's website. All references to sustained winds imply a 1-minute averaging period unless otherwise noted. Atlantic Tropical Activity for December --------------------------------------- Two tropical cyclones roamed Atlantic waters during December. The first was Hurricane Epsilon, which formed in late November and reached hurricane intensity on 2 December. Epsilon continued as a hurricane for five days--establishing a new record number of hurricane days for the month of December. Tropical Storm Zeta formed on 30 December and became the first inter-annual Atlantic tropical cyclone since Hurricane Alice in 1954-1955. While extremely interesting from a climatological point of view, Epsilon and Zeta roamed subtropical waters far removed from any land areas and were of concern only to shipping interests. The report on Hurricane Epsilon was included in the November summary--a short report on Zeta follows. As a reminder, just about all of the official TPC/NHC storm reports for 2005 Atlantic tropical cyclones are now available online at the following link: http://www.nhc.noaa.gov/2005atlan.shtml> TROPICAL STORM ZETA (TC-30) 30 December - 6 January ------------------------------------------- The official TPC/NHC storm report on Tropical Storm Zeta, co-authored by Richard Knabb and Daniel Brown, is now available on NHC's website. Tropical Storm Zeta, the 30th numbered cyclone and 27th tropical storm of the incredible record-breaking 2005 Atlantic hurricane season, became the first inter-annual tropical cyclone in 51 years, and only the second on record. The last tropical cyclone to form in December and continue into January was Hurricane Alice from 30 December 1954 to 5 January 1955. That particular hurricane was named as the first storm of 1955 when the Hurricane Hunters went out on 2 January to investigate a system for which ships had been reporting strong winds. The reconnaissance aircraft found a fully-developed hurricane, so being January, it was named Alice. Later the storm was traced to a disturbance first noted on 30 December 1954, so officially it is now considered the final tropical cyclone of 1954. Hurricane Alice, however, was not being carried operationally as a tropical cyclone at the moment when the big ball dropped in Times Square, so Tropical Storm Zeta has the distinction of being the first Atlantic cyclone for which real-time advisories were written in two different calendar years. Zeta's origins lay in the interaction between a weakening frontal boundary and an upper-tropospheric trough. A closed LOW formed along the surface trough on 29 December about 675 nm northwest of the Cape Verde Islands. Early on 30 December the system began to quickly acquire tropical characteristics and the first advisory on Tropical Storm Zeta was issued at 1700 UTC that day, placing the center about 930 nm southwest of the Azores with 45-kt winds. Over the next week the out-of-season storm meandered to the northwest, then southwestward, westward, and finally west-northwestward as it weakened. Zeta had to battle shear throughout its lifetime, but proved to be very tenacious. The peak intensity, 55 kts, was reached at two different times: at 1800 UTC on 1 January, and again at 0000 UTC on 3 January after weakening to 45 kts at 02/1200 UTC. Based on a careful post-storm study of the available data, it has been concluded that the original LOW became a tropical depression around 0000 UTC on 30 December and a tropical storm by 0600 UTC. The Atlantic Best Tracks file shows the aforementioned Hurricane Alice as reaching tropical storm intensity at 1200 UTC on 30 December, so Zeta falls short by six hours of tying the record for the latest tropical storm to form in any calendar year. More meteorological details of Tropical Storm Zeta may be found in the excellent NHC online report. A graphic depicting the operational track of Tropical Storm Zeta may be found at the following link: http://www.tropicalcyclone2005.com/database/2005/atlantic/BT-IMAGES/2005-30L-ZETA.gif> No deaths or damages have been attributed to Tropical Storm Zeta. (Report written by Gary Padgett, based in part on the official TPC/NHC report by Rich Knabb and Dan Brown) ************************************************************************* MEDITERRANEAN (MED) - Confines of the Mediterranean Sea Activity for December: 1 possible tropical or subtropical cyclone A Tale of Two Mediterranean Cyclones ------------------------------------ I am including this section to call attention to two cyclonic storms in the Mediterranean Sea during the final quarter of 2005. I do not have much information about either, but I just wanted to document them in case anyone is interested in trying to obtain satellite imagery and study them further. (1) The first system moved off the Libyan coast early on 26 October with strong convection and appeared to develop a circulation as it moved northeastward to just east of Sicily as a small, compact convective system. No eye was apparent in Meteosat imagery. Julian Heming sent me a couple of images of this system, one being a visible picture at 1100 UTC on 27 October. This image shows a very small system located just east of Sicily and south of the "toe" of Italy. Based on its appearance it does not seem likely that it would have been very intense. (2) The second system occurred in mid-December. A visible image taken at 0845 UTC on 15 December depicts a well-developed cyclonic system with a prominent eye-like feature centered between the island of Crete and the coast of Libya. It does in many ways resemble a small tropical or subtropical cyclone. The image also shows the entrainment of North African dust into the cyclone. The link to this particular image is: http://rapidfire.sci.gsfc.nasa.gov/realtime/single.php?2005349/crefl2_143.A2005349112500-2005349113000.500m.jpg> ************************************************************************* NORTHEAST PACIFIC (NEP) - North Pacific Ocean East of Longitude 180 Activity for December: No tropical cyclones ************************************************************************* NORTHWEST PACIFIC (NWP) - North Pacific Ocean West of Longitude 180 Activity for December: 1 tropical 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. In the companion tropical cyclone tracks file, I normally annotate track coordinates from some of the various Asian warning centers when their center positions differ from JTWC's by usually 40-50 nm or more. All references to sustained winds imply a 1-minute averaging period unless otherwise noted. Michael V. Padua of Naga City in the Philippines, owner of the Typhoon 2000 website, normally sends me cyclone tracks based upon warnings issued by the Japanese Meteorological Agency (JMA) and the Philippines' Atmospheric, Geophysical & Astronomical Services Administration (PAGASA). A very special thanks to Michael for the assistance he so reliably provides. In the title line for each storm I have referenced all the cyclone names/numbers I have available: JTWC's depression number, the JMA-assigned name (if any), JMA's tropical storm numeric designator, and PAGASA's name for systems forming in or passing through their area of warning responsibility. Northwest Pacific Tropical Activity for December ------------------------------------------------ The slackness in Northwest Pacific tropical cyclone activity which began in October continued into the final month of 2005. Only one tropical cyclone formed during the month, and it was classified as a tropical storm by JTWC only, and a weak one at that. Tropical Storm 25W (named Quedan by PAGASA) formed near the southwestern Philippines and moved generally westward across the South China Sea. While southeast of Vietnam on the 19th it became better organized and was upgraded to a minimal tropical storm by JTWC. The next day, however, it weakened and the remnants drifted west-southwestward toward the Malay Peninsula. A short report on this cyclone, written by Kevin Boyle, follows. TROPICAL STORM (TC-25W / QUEDAN) 16 - 22 December ------------------------------------- Tropical Storm 25W was first mentioned as a suspect area in JTWC's STWO at 0600 UTC 15 December when it was located approximately 95 nm south-southeast of Tandag, Philippines. PAGASA first classified the disturbance as a tropical depression at 16/1200 UTC, naming it Quedan. The system slowly organized in a low shear environment and under good divergence aloft, and two TCFAs were issued, first at 17/0200 UTC and then at 18/0200 UTC. The first warning was released at 18/1200 UTC, locating the centre 305 nm southeast of Nha Trang, Vietnam. TD-25W/ Quedan strengthened the northeast monsoon flow across the South China Sea as it interacted with a HIGH over central China. Tracking west to west-northwestwards, TD-25W strengthened and was upgraded to a 35-kt tropical storm at 0000 UTC 19 December, located approximately 260 nm south-southeast of Nha Trang, Vietnam. It reached a peak intensity of 40 kts twelve hours later. Thereafter, the system began to weaken and fall apart as it continued west to west- northwestwards into a hostile wind shear environment and cooler SSTs. It was downgraded to a tropical depression on JTWC's final warning, issued at 20/0600 UTC, after the LLCC had become fully-exposed and the deep convection had largely diminished. The final warning located the centre approximately 195 nm southeast of Ho Chi Minh, Vietnam. JMA continued to track the residual weak depression for another couple of days west-southwestwards until it reached the Malayan Peninsula near the Thai-Malaysian border around 22/0600 UTC. JMA never raised their 10-min avg MSW estimate above 30 kts and did not upgrade the system to a tropical storm. Therefore, this tropical cyclone was never assigned an international name. The Meteorological Department of Thailand also treated 25W/Quedan as a 30-kt tropical depression. A graphic depicting the track of this tropical storm may be found at the following link: http://www.tropicalcyclone2005.com/database/2005/w_pacific/BT-IMAGES/2005-25W-NONAME.gif> No damages or casualties have been reported in association with Tropical Storm 25W/Quedan. (Report written by Kevin Boyle) ************************************************************************* NORTH INDIAN OCEAN (NIO) - Bay of Bengal and Arabian Sea Activity for December: 2 cyclonic storms ** 1 severe cyclonic storm ++ ** - one of these was not classified as a cyclonic storm by IMD; another formed in November but was still active in early December ++ - system was not upgraded to 'severe cyclonic storm' status by IMD 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. North Indian Ocean Tropical Activity for December ------------------------------------------------- The fairly active fall transition season in the Bay of Bengal continued unabated into December. Cyclonic Storm Baaz, which developed late in November, was still on the charts during the first couple of days of December. Following that, two more tropical storms formed during the first half of the month, making this the first December since 1987 to see the formation of two tropical storms in the North Indian Ocean. Based on both JTWC's and TMD's analyses, Cyclonic Storm Fanoos reached hurricane intensity just off the southeastern Indian coast but weakened before making landfall. Around mid-month, Tropical Cyclone 07B formed just east of Sri Lanka but eventually dissipated without affecting any populated areas. The TMD also regarded TC-07B as a tropical storm, but RSMC New Delhi treated it only as a deep depression; hence, no name was assigned. Reports on both the December cyclones follow. CYCLONIC STORM FANOOS (BOB0504 / TC-06B) 5 - 12 December ----------------------------------------- Fanoos: contributed by Pakistan JTWC issued a STWO at 0200 UTC on 4 December which noted that an area of convection had persisted over the Bay of Bengal about 850 nm east- southeast of Madras, India. Satellite imagery depicted a developing LLCC near the convection. A gradient-level analysis indicated that the developing circulation was embedded within a region of sharp troughing and increasing 850-mb vorticity values, and a concurrent upper-level analysis revealed that the disturbance was under moderate vertical shear with favorable poleward divergence. The development potential was assessed as 'poor', but this was upgraded to 'fair' 24 hours later after convection had increased over the LLCC, which itself was better defined than on the previous day. A TCFA was issued at 1430 on the 5th of December, upgrading the potential for development to 'good'. The system by that time had moved westward to a point approximately 650 nm east of Madras. The TCFA noted that the MSW were estimated at 30-35 kts, so if the system had been located in the Northwest Pacific basin, it would have already been classified as a tropical depression or possibly even a tropical storm. The Thai Meteorological Department (TMD) began classifying the LOW as a tropical depression at 05/1800 UTC, and JTWC issued their first warning on Tropical Cyclone 06B at 06/0000 UTC, locating the center about 550 nm east of Madras and moving northwestward at 7 kts. The cyclone was forecast to move westward along the southwestern periphery of a low to mid-level steering ridge, but by late on the 6th the steering flow was making a transition from the ridge to the northeast to a more dominant ridge to the west. This resulted in a southwestward track on the 7th and into the 8th of December. The cyclone increased in intensity slowly due to the presence of moderate vertical shear. The IMD had classified the system as a deep depression at 0900 UTC on 6 December, and at 0300 UTC on the 7th upgraded it to cyclonic storm status and assigned the name Fanoos--the 4th named North Indian Ocean cyclone of 2005. Cyclonic Storm Fanoos continued to slowly increase in intensity as it returned to a westerly track on the 8th. The ridge over the eastern Arabian Sea, which had induced the southwesterly motion, was weakening and a ridge over the Bay of Bengal was expected to build to the west. SAB's Dvorak ratings reached T4.0 (65 kts) as early as 08/0830 UTC, but JTWC was more conservative with their intensity estimates, keeping Fanoos at 55 kts through the 8th and finally reaching a peak of 65 kts at 1800 UTC on the 9th. The cyclone at that time was located approximately 165 nm south-southeast of Madras, moving west at 9 kts. Fanoos moved inland on the southeast Indian coast near Vedaranniyam with a MSW of about 50-55 kts around 0300 UTC on 10 December, and once inland had weakened into a depression by 1800 UTC. The TMD continued to track the weakening system west-southwestward across southern India and into the southeastern Arabian Sea through 12/0000 UTC. The TMD's peak intensity for Fanoos was also 65 kts, but treated as a 10-min avg. This agrees with JTWC's and SAB's assessments that Fanoos reached hurricane intensity. TMD's landfall intensity was also in the same range as that estimated by JTWC. New Delhi, however, never estimated the intensity of Fanoos to be higher than 40 kts, and had downgraded the system to a deep depression (i.e., 30 kts) before it made landfall. A graphic displaying the track of Cyclonic Storm Fanoos may be found at the following link: http://www.tropicalcyclone2005.com/database/2005/indian/BT-IMAGES/2005-06B-FANOOS.gif> There were no fatalities reported in association with Cyclonic Storm Fanoos. However, the heavy rains associated with the dying storm were responsible for wreaking havoc to agricultural crops in the Tamil Nadu region, especially in the districts of Thanjavur and Nagapattinam. Following are two links which have some additional information on the effects of Fanoos: http://www.telegraphindia.com/1051211/asp/nation/story_5586447.asp> http://www.thehindubusinessline.com/2005/12/11/stories/2005121103630100.htm> (Report written by Gary Padgett) TROPICAL CYCLONE (TC-07B) 15 - 24 December ------------------------------------ The third tropical cyclone to form in the Bay of Bengal in less than three weeks had its beginnings in a persistent area of convection which formed on the 14th about 600 nm east of Colombo, Sri Lanka. Satellite imagery revealed a broad but symmetric area of low-level turning with deep convection on the northern periphery. The disturbance was located under low vertical shear with good outflow and increasing 850-mb vorticity. The development potential was upgraded to 'fair' at 1200 UTC on the 15th since the LLCC had become well-defined. The disturbance continued to move to the west, and by 2000 UTC on 16 December was located about 250 nm east of Colombo. A 16/1510 UTC SSM/I pass as well as multi-spectral satellite imagery had shown deep convection increasing over the LLCC, so JTWC issued a TCFA at that time. In the meantime, IMD had classified the system as a depression as early at 15/1200 UTC. The Thai Meteorological Department (TMD) began issuing bulletins on the tropical depression at 17/0000 UTC, and at the same time JTWC issued their first warning on Tropical Cyclone 07B. The center was then located about 220 nm east of Colombo and moving westward at 6 kts along the southern periphery of a mid-level ridge building over the Bay of Bengal. The initial intensity was set at 35 kts. Shortly afterward, however, TC-07B shifted to a north-northwestward track which it would follow for more than two days. The intensity remained steady at first, but at 0600 UTC on 18 December JTWC bumped up the MSW to 50 kts--the peak for the storm. It was then located just under 200 nm southeast of Madras, India. TC-07B was caught in a broad, mid-level cyclonic environment with separate ridges to the east and west. As the influence of the ridge centered over Indochina lessened, the cyclone was forecast to track slowly poleward and roughly parallel to the coast of India. This was indeed what happened. JTWC decreased their MSW estimate to 45 kts at 1800 UTC due to weakening convection and increasing shear, but TMD upped their intensity to 45 kts at the same time. Also, satellite intensity estimates from SAB reached a peak of T3.5--55 kts--at 1430 UTC on 19 December. Movement became slow and erratic on the 19th and the storm drifted generally to the east for a couple of days. JTWC's intensity remained at 45 kts through 20/0000 UTC, then began to slowly decline. At 1200 UTC the MSW was lowered to 40 kts. Vertical wind shear was moderate and the LLCC had become partially-exposed. By late on the 21st a mid- latitude trough over northern India had begun to interact with the cyclone and it began to track northeastward. The weakening continued and JTWC issued their final warning at 22/0000 UTC, placing the 25-kt center approximately 310 nm east of Madras and moving northeastward at 9 kts. The TMD continued to track the system through 24/0000 UTC when it had reached a point just west of the coast of Myanmar. The peak 10-min avg MSW estimated by the TMD was 45 kts, in good agreement with JTWC and SAB. New Delhi, however, never upgraded TC-07B to cyclonic storm status, estimating the peak intensity at 30 kts. Hence, no name was assigned to the system. A graphic displaying the track of Tropical Cyclone 07B may be found at the following link: http://www.tropicalcyclone2005.com/database/2005/indian/BT-IMAGES/2005-07B-NONAME.gif> No damage or casualties are known to have resulted from this tropical cyclone. (Report written by Gary Padgett) ************************************************************************* SOUTHWEST INDIAN OCEAN (SWI) - South Indian Ocean West of Longitude 90E Activity for December: 1 tropical depression ** ** - system formed in the Western Australian region and was treated as a cyclone of gale intensity by JTWC Southwest Indian Ocean Tropical Activity for December ----------------------------------------------------- No tropical systems formed over South Indian Ocean waters west of 90E during December. A tropical LOW which originated in the Australian Region moved westward across 90E and was numbered Tropical Depression 06 by MFR. JTWC treated this system as a minimal tropical storm and designated it as TC-04S. A short report on this system is included in the following section of this summary covering the Northwest Australia/ Southeast Indian Ocean region. ************************************************************************* NORTHWEST AUSTRALIA/SOUTHEAST INDIAN OCEAN (AUW) - From 90E to 135E Activity for December: 1 tropical LOW ** ** - system moved into the Southwest Indian Ocean basin and was treated as a cyclone of gale intensity by JTWC 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. For portions of the system's history lying west of longitude 90E, the following applies: 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. Northwest Australia/Southeast Indian Ocean Tropical Activity for December ------------------------------------------ A tropical LOW formed in the western portion of BoM Perth's AOR late in the month and was designated as TC-04S by JTWC. This system moved westward across 90E into the Southwest Indian Ocean basin and was numbered Tropical Depression 06 by RSMC La Reunion. A short report on this system follows. TROPICAL DEPRESSION (MFR-06 / TC-04S) 21 - 29 December --------------------------------------- The daily STWO issued by BoM Perth on 19 December mentioned a weak tropical LOW located just west of the boundary of their AOR (longitude 90E) which had a moderate chance of developing in the next three days. The LOW persisted and shifted slightly eastward into Perth's region of responsibility. Since development into a tropical cyclone was a possibility, gale warnings were initiated at 1800 UTC on 21 December. The initial warning placed the center approximately 400 nm west- northwest of the Cocos Islands. The LOW initially moved southward, then curved to the west-southwest, moving out of Perth's AOR without further intensification around 0300 UTC on the 23rd. JTWC included the system in a STWO issued at 22/1800 UTC, noting that convection was displaced to the southwest of a partially-exposed LLCC. Upon moving west of 90E early on 23 December, MFR assumed responsibility for issuing marine bulletins, numbering the system as Tropical Depression 06. After around 0000 UTC on 24 December the tropical depression's track became more southwesterly as it was steered along the periphery of a subtropical ridge to the southeast. At 24/0100 UTC JTWC issued an interim STWO, upgrading the potential for development to 'fair' based upon an increase in convection near the center of circulation. The first JTWC warning on TC-04S was issued at 24/0600 UTC with the MSW estimated at 35 kts (1-min avg). This was the peak intensity estimated by JTWC. Shortly afterward, MFR downgraded the system to a 25-kt tropical disturbance with 30-kt winds possible in the southern semi- circle well-removed from the center. The system at the time was located approximately 750 nm east-southeast of Diego Garcia. Easterly shear continued to inhibit intensification as the disturbance continued to track southwestward. JTWC issued their final warning on TC-04S at 1800 UTC on 25 December--at the same time MFR reduced their estimate of the central winds to only 20 kts. The final warning was issued by MFR at 0600 UTC on 26 December and placed the center about 400 nm south-southeast of Diego Garcia. The story of Tropical Disturbance 06 wasn't quite finished, however. MFR resumed bulletins on the system at 27/0600 UTC since environmental conditions had become slightly more favorable and deep convection had re-organized during the night. The center by that time had moved to a position about 465 nm northeast of Rodrigues with the southwesterly motion continuing. The MSW was estimated at 25 kts, but the system remained poorly organized and was unable to strengthen further. Shear continued to plague the disturbance and it began to weaken again on the 28th. The second "final" warning from MFR was issued at 0600 UTC on 29 December and placed the weak 20-kt LLCC about 150 nm west-southwest of Rodrigues. A graphic displaying the track of this system may be found at the following link: http://www.tropicalcyclone2005.com/database/2006/SOHEM/BT-IMAGES/2006-04S-NONAME.gif> No damage or casualties have been attributed to this system. (Report written by Gary Padgett) ************************************************************************* NORTHEAST AUSTRALIA/CORAL SEA (AUE) - From 135E to 160E Activity for December: No tropical cyclones ************************************************************************* SOUTH PACIFIC (SPA) - South Pacific Ocean East of Longitude 160E Activity for December: 3 tropical depressions 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. South Pacific Tropical Activity for December -------------------------------------------- The 2005-2006 tropical cyclone season in the South Pacific Ocean east of 160E got underway in December with the formation of three tropical depressions. None of these, however, developed into tropical cyclones (i.e., tropical storms). All three of these systems formed in regions of moderate vertical shear and in general moved into areas of even higher shear. RSMC Nadi numbered these three systems but issued no gale warnings. None of the three depressions were likely to have generated central winds any higher than 20-25 kts, and no tracks were included for them in the companion tropical cyclone tracks file. The first of the trio, TD-01F, was first mentioned on 1 December when it was located about 225 nm southeast of American Samoa. This short-lived system moved eastward and was last referenced at 2100 UTC on the 2nd when it was located about 85 nm east of Palmerston Island. A Tropical Disturbance Summary issued at 03/1800 UTC noted that TD-02F had formed and was located about 475 nm northeast of Port Vila, Vanuatu. This depression moved slowly and erratically over the next few days generally in a southerly direction. The final reference to this system at 2100 UTC on 6 December placed it roughly 235 nm north- northeast of Port Vila. The third system, TD-03F, was quite long-lived, being in existence for 10 days in mid-December. At 1800 UTC on the 8th a Tropical Disturbance Summary noted that it was located about 125 nm northeast of Pago Pago, American Samoa. The depression moved very slowly and erratically, the center being relocated at times. It perhaps had the best chance of the three to develop, but some drier air which got entrained into the system tended to inhibit the maintenance of deep convection, and as it moved farther to the southeast, vertical shear increased. The final reference to TD-03F, at 18/0600 UTC, placed the center about 450 nm south of Tahiti. ************************************************************************* 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: ftp://ftp.nhc.noaa.gov/pub/products/nhc/recon/> Information regarding how to interpret the coded reconnaissance messages may be found at the following URL: http://www.nhc.noaa.gov/reconlist.shtml> 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: http://www.nhc.noaa.gov/archive/2004/index.shtml> Links to tropical products archives for earlier years are available at the following URL: http://www.nhc.noaa.gov/pastall.shtml> JTWC warnings for past storms are archived on the NRL Monterry website: http://www.nrlmry.navy.mil/tc_pages/tc_home.html> 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: http://www.nrlmry.navy.mil/tc_pages/tc_home.html> http://cimss.ssec.wisc.edu/tropic/tropic.html> 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: http://www.ssd.noaa.gov/PS/TROP/trop-epac.html> (2) For the Atlantic, Gulf of Mexico and Caribbean Sea: http://www.ssd.noaa.gov/PS/TROP/trop-atl.html> 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): http://australiasevereweather.com/cyclones/> http://www.typhoon2000.ph> http://mpittweather.com> ftp://ftp.aoml.noaa.gov/hrd/pub/landsea/padgett/> http://www.tropicalcyclone2005.com/> 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.metoffice.gov.uk/weather/tropicalcyclone> 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: http://199.10.200.33/jtwc.html> Also, TPC/NHC has available on its webpage nice "technicolor" tracking charts for the 2004 Atlantic and Eastern North Pacific tropical cyclones; also, storm reports for all the 2004 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] Simon Clarke (Northeast Australia/Coral Sea, South Pacific) E-mail: [email protected] ************************************************************************* *************************************************************************
Document: summ0512.htm
Updated: 26th March 2006 |
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