WDPS31 PGTW 040300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 24P (TWENTYFOUR) 
WARNING NR 001//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 14.2S 150.8E
   INITIAL INTENSITY: 35 KTS
   GEOGRAPHIC REFERENCE: 331 NM EAST-NORTHEAST OF CAIRNS, AUSTRALIA
   MOVEMENT PAST 6 HOURS: SOUTH-SOUTHEASTWARD AT 02 KTS
   SIGNIFICANT WAVE HEIGHT: 15 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A FULLY 
EXPOSED, TIGHTLY WOUND, LOW LEVEL CIRCULATION CENTER (LLCC). THE LLCC
EMERGED OVER THE PAST TWO HOURS AS DEEP CONVECTION SHEARED WESTWARD.
A 032239Z GMI COLOR-ENHANCED 89GHZ MICROWAVE IMAGE CONFIRMED A WELL-
DEFINED LLCC, WITH THE BULK OF DEEP CONVECTION DISPLACED OVER A
MID-LEVEL VORTEX TO THE WEST. THE INITIAL POSITION IS ASSESSED WITH
HIGH CONFIDENCE BASED ON THE CLEARLY DEFINED CIRCULATION IN THE MSI.
THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE. THE PGTW
DVORAK CURRENT INTENSITY ESTIMATE IS T2.5, WHILE KNES IS AT T3.0;
HOWEVER, THE KNES FIX POSITION IS CENTERED ON SHEARED CONVECTIVE
ELEMENTS, LIKELY OVERESTIMATING THE INTENSITY. A 031952Z SMOS PASS
REVEALED A SWATH OF 30-35 KNOT WINDS ALONG THE WESTERN AND NORTHERN
QUADRANTS OF THE LLCC, SUPPORTING THE INITIAL INTENSITY ESTIMATE.
ENVIRONMENTAL CONDITIONS ARE MARGINALLY FAVORABLE, WITH WARM SSTS
AND MODERATE UPPER-LEVEL DIVERGENCE, LARGELY OFFSET BY LOW TO
MODERATE EASTERLY VERTICAL WIND SHEAR (VWS).

INITIAL WIND RADII BASIS: SMOS AND SCATTEROMETER DATA 

CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) SITUATED OVER CENTRAL AUSTRALIA. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.5 - 35 KTS
   KNES: T3.0 - 45 KTS
   CIMSS D-PRINT: 32 KTS AT 040000Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
   VWS: 15-20 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: MODERATE POLEWARD AND EQUATORWARD

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

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING
MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY.

FORECAST DISCUSSION: TROPICAL CYCLONE (TC) 24P HAS REMAINED QUASI-
STATIONARY OVER THE PAST SIX HOURS, AS THE VORTEX STRUCTURE BECAME
VERTICALLLY DECOUPLED DUE TO PERSISTENT MODERATE EASTERLY SHEAR.
CONVECTIVE REDEVELOPMENT AND VORTEX REALIGNMENT ARE ANTICIPATED
WITHIN THE NEXT SIX HOURS. SUBSEQUENT TO REORGANIZATION, THE SYSTEM
WILL TRACK SOUTHWESTWARD ALONG THE NORTHERN PERIPHERY OF THE
DEEP-LAYER STR TO THE SOUTH. THE SYSTEM WILL MAINTAIN THIS
TRAJECTORY THROUGH THE FORECAST PERIOD, WITH LANDFALL PROJECTED IN
THE VICINITY OF CAIRNS, AUSTRALIA, NEAR TAU 48. REGARDING INTENSITY, 
THE SYSTEM IS EXPECTED TO UNDERGO GRADUAL INTENSIFICATION AS THE 
VORTEX CONSOLIDATES. PEAK INTENSITY OF 45 KNOTS IS FORECAST BY TAU 24; 
HOWEVER, MID-LEVEL DRY AIR ENTRAINMENT AND INCREASED SHEAR POST-TAU 24 
WILL LIKELY INHIBIT FURTHER INTENSIFICATION PRIOR TO LANDFALL. UPON 
MOVING INLAND, THE SYSTEM WILL WEAKEN RAPIDLY DUE TO LAND INTERACTION 
AND FULLY DISSIPATE AS A TROPICAL CYCLONE SHORTLY BEFORE TAU 72.

MODEL DISCUSSION: DETERMINISTIC, ENSEMBLE AND ARTIFICIAL
INTELLIGENCE (AI) TRACK GUIDANCE ARE IN STRONG AGREEMENT FOR THE
DURATION OF THE FORECAST PERIOD. ALL CONSENSUS MEMBERS INDICATE SLOW 
MEAN MOTION THROUGH TAU 12, FOLLOWED BY SOUTHWESTWARD ACCELERATION AS 
THE STEERING GRADIENT TIGHTENS. CROSS-TRACK SPREAD IS APPROXIMATELY 
100NM AT LANDFALL (TAU 48), WITH THE UKMET (EGRR) DEFINING THE 
NORTHERN ENVELOPE AND ECMWF DEFINING THE SOUTHERN, PLACING THE MULTI-
MODEL CONSENSUS (CONW) DIRECTLY OVER CAIRNS. BY TAU 72, CROSS-TRACK 
UNCERTAINTY INCREASES SLIGHTLY TO 135NM. WHILE ENSEMBLE GUIDANCE IS 
LARGELY CONSISTENT, THE GEFS DEPICTS SIGNIFICANT SPREAD WITH OUTLIER 
MEMBERS EXTENDING FROM THE GULF OF CARPENTARIA TO EAST OF BRISBANE, 
WHICH INTRODUCES A MODERATE AMOUNT OF UNCERTAINTY. THE JTWC FORECAST 
IS POSITIONED NEAR THE CONSENSUS MEAN WITH MEDIUM CONFIDENCE. 
INTENSITY GUIDANCE IS TIGHTLY CLUSTERED, AND THE JTWC FORECAST ALIGNS 
WITH HAFS-A, HWRF, AND COAMPS-TC WITH HIGH CONFIDENCE. 

FORECAST CONFIDENCE:
   TRACK 00-72 HR: MEDIUM
   INTENSITY 00-72 HR: HIGH//
NNNN