WDIO31 PGTW 030900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 08B (MICHAUNG)   
WARNING NR 002//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 11.8N 82.7E
   INITIAL INTENSITY: 35 KTS
   GEOGRAPHIC REFERENCE: 725 NM SOUTH-SOUTHWEST OF KOLKATA, INDIA
   MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 05 KTS
   SIGNIFICANT WAVE HEIGHT: 16 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A
CONSOLIDATING SYSTEM WITH DEEP CONVECTIVE BANDING WRAPPING INTO A
BROAD LOW-LEVEL CIRCULATION CENTER (LLCC). RECENT MICROWAVE IMAGERY, 
INCLUDING A 030036Z SSMIS 91 GHZ MICROWAVE IMAGE, INDICATES IMPROVED 
CONVECTIVE STRUCTURE WITH TIGHTLY-CURVED BANDING WRAPPING INTO A MORE 
DEFINED LLCC. UPPER-LEVEL OUTFLOW REMAINS ROBUST WITH RADIAL OUTFLOW 
AND ENHANCED POLEWARD OUTFLOW INTO THE MIDLATITUDE WESTERLIES TO THE 
NORTH. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON 
A 030430Z ASCAT-B BULLSEYE IMAGE SHOWING A WELL-DEFINED CIRCULATION
CENTER AND 30-35 KNOT WINDS. THE INITIAL INTENSITY OF 35 KTS IS
ASSESSED WITH HIGH CONFIDENCE BASED ON THE ASCAT-B DATA AS WELL AS
THE PGTW AND DEMS DVORAK ESTIMATES.

INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR)
POSITIONED TO THE EAST AND NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.5 - 35 KTS
   KNES: T3.0 - 45 KTS
   DEMS: T2.5 - 35 KTS
   CIMSS ADT: 37 KTS AT 030700Z
   CIMSS AIDT: 33 KTS AT 030700Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE
   VWS: 10-15 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: STRONG RADIAL

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TROPICAL CYCLONE (TC) 08B IS FORECAST TO TRACK
NORTHWESTWARD ALONG THE SOUTHWEST PERIPHERY OF THE STR THROUGH TAU
24 WITH A NORTH-NORTHWESTWARD TURN THROUGH TAU 36. TC 08B IS EXPECTED
TO STEADILY INTENSIFY DUE TO THE HIGHLY FAVORABLE ENVIRONMENTAL 
CONDITIONS THROUGH TAU 36 TO A PEAK OF 60 KNOTS BY TAU 36. AFTER TAU 
36, A MIDLATITUDE SHORTWAVE TROUGH IS FORECAST TO DIG INTO NORTHERN 
INDIA, WHICH WILL ERODE AND REORIENT THE STR INTO A NORTH-SOUTH 
ORIENTATION. TC 08B WILL GRADUALLY WEAKEN AS IT APPROACHES THE COAST 
OF INDIA WITH LANDFALL NEAR TAU 48. AFTER TAU 48, TC 08B WILL RECURVE
NORTHWARD TO NORTHEASTWARD AND WEAKEN RAPIDLY AS IT TRACKS INLAND AND 
ENCOUNTERS THE MIDLATITUDE WESTERLIES AND STRONG VWS (20 KNOTS AT TAU 
48 TO 45 KNOTS AT TAU 96). AFTER THE SYSTEM DISSIPATES NEAR TAU 96, 
THE REMNANTS MAY TRACK BACK OVER THE NORTHERN BAY OF BENGAL BUT ARE 
NOT EXPECTED TO REGENERATE DUE TO THE HOSTILE UPPER-LEVEL CONDITIONS.      

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT
WITH A CROSS-TRACK SPREAD OF 115 NM AT TAU 48 DIVERGING TO 165NM AT
TAU 72 LENDING MEDIUM CONFIDENCE TO THE JTWC TRACK FORECAST THROUGH
TAU 72. AFTER TAU 72, NUMERICAL MODEL GUIDANCE IS IN POOR AGREEMENT
WITH A VERY LARGE SPREAD. THE 021800Z ECMWF ENSEMBLE (EPS) SUPPORTS
THE JTWC FORECAST TRACK BUT SHOWS FOUR SOLUTIONS TRACKING THE
SYSTEM EAST OF INDIA WITH HIGHER PEAK INTENSITY. THE 030000Z GFS 
ENSEMBLE (GEFS) INDICATES A SMALL NUMBER (LOW PROBABILITY) OF 
SOLUTIONS WITH A MORE NORTHWARD TRACK AND PROLONGED PERIOD OVER 
WATER. RELIABLE INTENSITY GUIDANCE INDICATES A PEAK INTENSITY RANGING 
FROM 45 TO 50 KNOTS WITH HAFS-A AND COAMPS-TC (BOTH GFS AND NAVGEM
VERSIONS) INDICATING A PEAK INTENSITY OF 45 KNOTS. THE JTWC INTENSITY 
CONSENSUS (ICNW) REVEALS A PEAK INTENSITY OF 50 KNOTS. HOWEVER,
THE JTWC PEAK INTENSITY OF 60 KNOTS IS MAINTAINED BASED ON THE
HIGHLY FAVORABLE ENVIRONMENTAL CONDITIONS. THE JTWC INTENSITY 
FORECAST IS FURTHER BOLSTERED BY THE TRIGGERING OF RAPID 
INTENSIFICATION GUIDANCE AND THE 030000Z COAMPS-TC (GFS VERSION) 
ENSEMBLE, WHICH INDICATES A 40 TO 50 PERCENT PROBABILITY FOR RAPID 
INTENSICATION THROUGH TAU 18.  

FORECAST CONFIDENCE:
   TRACK 0 - 72 HR: MEDIUM
   TRACK 72-120 HR: LOW
   INTENSITY 0 - 72 HR: MEDIUM
   INTENSITY 72-120 HR: HIGH//
NNNN