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Annual Tropical Cyclone Report 2009

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Executive Summary

The Annual Tropical Cyclone Report (ATCR) is prepared by the staff of the Joint Typhoon Warning Center (JTWC), a combined United States Air Force/Navy organization under the operational command of the Commanding Officer, Naval Maritime Forecast Center/Joint Typhoon Warning Center (NMFC/JTWC), Pearl Harbor, Hawaii. JTWC was established on 1 May 1959 when Commander-inChief, US Pacific Command (USCINCPAC) directed Commander-in-Chief, Pacific Fleet to provide a single tropical cyclone warning center for the western North Pacific region. Subsequent USCINCPAC directive further tasked Commander, Pacific Air Force to provide for tropical cyclone (TC) reconnaissance support to the JTWC. Currently, JTWC operations are guided by USPACOM Instruction 0539.1.

The JTWC celebrated its 50th Anniversary in late April 2009 at a ceremony at the Ford Island Conference Center. The guest speaker was RDML Tom Copeman, Pacific Fleet Deputy Chief of Staff for Operations, Training and Readiness. In addition, the event included speeches from CAPT Dean Sadanaga, Director of Weather Services, Naval Oceanography Operations Command, Col Scott Van Blarcum, Chief of Weather Resources and Programs, Headquarters Air Force, CAPT Grant Cooper, Commanding Officer NMFC/JTWC, and Lt Col Kurt Brueske, Commander, 17th Operational Weather Squadron. All speakers strongly reiterated the need for JTWC to support US Department of Defense operations. The ceremony concluded with former Commanding Officer CAPT (retired) Ty Aldinger and former Director Lt Col (retired) Chip Guard cutting ceremonial cakes for the 100 or so attendees.

This edition of the ATCR documents the TC season and details operationally or meteorologically significant TCs that highlight significant challenges and/or shortfalls in the TC warning system and that serve as a focal point for research and development efforts.

Below normal activity in the western North Pacific Ocean continued in 2009, with 28 TCs observed compared to the long term average of 31. The North Indian, South Indian and South Pacific Oceans experienced normal activity with 5, 18, and 9 TCs respectively compared to the long term averages of 5, 18, and 10.

Two cyclones that posed significant challenges to JTWC were Super Typhoon (STY) 22W (Lupit) and STY 19W (Parma). STY 22W formed southeast of Guam and initially moved to the west-northwest then west into the Philippine Sea where it moved very erratically. During passage through the Philippine Sea this cyclone made turns to the northeast, then northwest, then southwest and then sharply northeast again, resulting in large 4 and 5 day forecast errors. STY 19W was another notable cyclone that crossed northern Luzon Island three times prior to transiting the South China Sea and making landfall on Hainan Island and then northern Vietnam.

Official and media reports indicated that Typhoon 09W (Morakot) was the most destructive cyclone in the western North Pacific in 2009, with significant damage reported on Taiwan and Fujian, Zhejiang and Jiangsu provinces, China as well as approximately 650+ fatalities reported mainly due to landslides from extremely heavy rainfall. STY 20W (Melor) was the only system to make landfall near DoD installations in 2009. This cyclone formed to the east of Guam, crossed the northern Marianas Islands and attained super typhoon intensity to the southeast of Okinawa Island. STY 20W subsequently went ashore about 150 miles southwest of several DoD installations in the Kanto Plain as a minimal typhoon.

The primary operational changes that occurred in 2009 were the long-line transmission of microwave position estimates in the satellite position and intensity bulletins and the extension of southern hemisphere warnings from 48 hours to 120 hours. Weather satellite data remained the mainstay of the TC reconnaissance mission at the JTWC.

Satellite analysts exploited a wide variety of conventional and microwave satellite data to produce over 10,000 position and intensity estimates (fixes), primarily using the USAF Mark IVB and the USN FMQ17 satellite direct readout systems to produce these fixes. The JTWC also used geo-located microwave satellite imagery overlays available via the Automated Tropical Cyclone Forecast (ATCF) system from Fleet Numerical Meteorology and Oceanography Center and the Naval Research Lab Monterey to make TC fixes. On 23 November 2009 at around 0700Z, the antenna motor on NASA’s QuikSCAT failed, ending a long era in ocean surface vector wind data. This loss is expected to have negative impacts on the JTWC reconnaissance and forecast mission.

JTWC continued to collaborate with TC forecast support and research organizations such as the Fleet Numerical Meteorology and Oceanography Center (FNMOC), Naval Research Laboratory, Monterey (NRLMRY), Naval Post Graduate School, the Office of Naval Research, and Air Force Weather Agency (AFWA) for continued development of numerical TC models and forecast aids. Of note, in 2009, improvements to the Navy’s version of the Geophysical Fluid Dynamics Lab mesoscale typhoon model (GFDN) were completed and the GFDN became a coupled air/ocean TC forecast model in the western North Pacific. Work continues to add 3-dimensional ocean coupling in other basins within the JTWC area of responsibility. Furthermore, the AFWA has migrated from the MM5 to WRF and is scheduled to provide TC track and intensity information from WRF in 2010. JTWC has also requested the implementation of the Hurricane Weather and Research Forecast model (H-WRF) for use in the western North Pacific in support of National Weather Service local forecast operations in Micronesia.

Late in 2009, operational support of the ATCF system was funded and scheduled to be moved to FNMOC, but instead was transferred to the N6 Department at NMFC/JTWC, with technical reach-back assistance from NRLMRY.
Behind all these efforts are incredible people - the dedicated team of men and women, military and civilian at NMFC/JTWC. Special thanks to the entire N6 Department for their outstanding IT support, Mr. Craig Motell for his computer automation efforts, and the administrative and budget staff who worked tirelessly to ensure JTWC had the necessary resources to get the mission done.

Special thanks also to: FNMOC for their operational data and modeling support; the NRLMRY for its dedicated research; the National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service for satellite support; for their high quality support; all the men and women of the ships and facilities ashore throughout the JTWC area of responsibility; Dr. John Knaff, Mr. Jeff Hawkins, Dr. Mark DeMaria, and Mr. Chris Velden for their continuing efforts to exploit remote sensing technologies in new and innovative ways; Mr. Charles R. “Buck” Sampson, Ms. Ann Schrader, Mr. Mike Frost, and Mr. Chris Sisko for their support and continued development of the ATCF system.