WDIO31 PGTW 090900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 06B (MANDOUS) 
WARNING NR 007//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 11.2N 81.4E
   INITIAL INTENSITY: 50 KTS
   GEOGRAPHIC REFERENCE: 130 NM SOUTH-SOUTHEAST OF CHENNAI, INDIA
   MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 05 KTS
   SIGNIFICANT WAVE HEIGHT: 14 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A WELL
DEFINED TROPICAL STORM WITH A FULLY OBSCURED LOW LEVEL CIRCULATION
CENTER (LLCC). THE NORTHEASTERN QUADRANT OF THE CIRCULATION IS
FULLY EXPOSED, REVEALING TIGHT LOW LEVEL BANDING FEATURES. A
090227Z 89GHZ MICROWAVE IMAGE REVEALS A DISCRETE BROAD CIRCULATION
CENTER WITH BANDING FEATURES IN ALL QUADRANTS. THE INITIAL POSITION
IS PLACED WITH HIGH CONFIDENCE BASED ON MSI AND MICROWAVE IMAGERY. 
THE INITIAL INTENSITY OF 50 KTS IS ASSESSED WITH HIGH CONFIDENCE
BASED ON AN AGREEMENT BETWEEN AGENCY DVORAK FIXES AND CIMSS SATCON
AND ADT ALL OF WHICH INDICATE 50 KTS.

INITIAL WIND RADII BASIS: PERSISTENCE 

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE
NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.5 - 55 KTS
   KNES: T2.0 - 30 KTS
   CIMSS SATCON: 53 KTS AT 090251Z
   CIMSS ADT: 49 KTS AT 090315Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
   VWS: 15-20 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: MODERATE POLEWARD
   OTHER FACTORS: INCREASING LAND INTERACTION WITH INDIA

ANALYSIS CONFIDENCE:
   INITIAL POSITION: HIGH
   INITIAL INTENSITY: MEDIUM
   INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TC 06B MANDOUS IS FORECAST TO CONTINUE
TRACKING NORTHWESTWARD UNDER THE STEERING INFLUENCE OF THE STR TO
THE NORTHEAST. AS 06B APPROACHES MAINLAND INDIA THROUGH TAU 12,
SYSTEM INTENSITIES WILL CONTINUE TO STEADILY DECLINE DUE TO
INCREASING VERTICAL WIND SHEAR (VWS) AND LAND INTERACTION. AFTER
TAU 12, THE SYSTEM IS FORECAST TO MAKE LANDFALL SOUTH OF CHENNAI
BEFORE TRACKING INLAND AND CONTINUING TO WEAKEN. BY TAU 36, THE
SYSTEM IS FORECAST TO SUCCUMB TO INCREASED SHEAR AND LAND
INTERACTION, RESULTING IN DISSIPATION.

MODEL DISCUSSION: WITH THE EXCEPTION OF UKMET-ENSEMBLE WHICH
CARRIES THE SYSTEM FURTHER NORTH, NUMERICAL MODELS ARE IN GOOD
AGREEMENT THAT 06B WILL MAKE LANDFALL AFTER TAU 12 AND SOUTH OF
CHENNAI, BEFORE PROCEEDING INLAND UNTIL DISSIPATION NEAR TAU 36.
RELIABLE MODEL INTENSITY GUIDANCE IS ALSO IN GOOD AGREEMENT WITH
ALL MEMBERS INDICATING A GRADUAL WEAKENING TREND THROUGH THE
FORECAST PERIOD. FOR THESE REASONS THE JTWC TRACK AND INTENSITY
FORECAST IS PLACED WITH HIGH CONFIDENCE.

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: HIGH
   INTENSITY 0 - 72 HR: HIGH//
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