WDPS31 PGTW 070900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03P (JASPER)     
WARNING NR 010//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 12.8S 156.8E
   INITIAL INTENSITY: 90 KTS
   GEOGRAPHIC REFERENCE: 684 NM EAST-NORTHEAST OF CAIRNS, AUSTRALIA
   MOVEMENT PAST 6 HOURS: SOUTHWARD AT 05 KTS
   SIGNIFICANT WAVE HEIGHT: 35 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TROPICAL CYCLONE (TC) 03P HAS FLIRTED WITH EYE FORMATION OVER THE
PAST TWELVE HOURS AS INDICATED IN ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI). RECENT MSI REVEALS DEEP CONVECTION CYCLING RAPIDLY
AROUND A CLOUD-FILLED EYE. FORTUNATELY, A 070525Z SSMIS 91 GHZ
COLOR COMPOSITE MICROWAVE IMAGE SHOWS A 25 TO 30 NM DIAMETER,
WELL-DEFINED MICROWAVE EYE FEATURE, WHICH SUPPORTS THE INITIAL
POSITION WITH HIGH CONFIDENCE. THE INITIAL INTENSITY OF 90 KTS IS
ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE KNES AND PGTW DVORAK
INTENSITY ESTIMATES. CIMSS OBJECTIVE ESTIMATES ALSO SUPPORT THE
INTENSITY ESTIMATE AND RANGE FROM 87 TO 92 KNOTS. DUE TO THE LACK
OF WIND SPEED IMAGERY, THERE IS LOW CONFIDENCE IN THE WIND RADII
ANALYSIS.

INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: WEAK SUBTROPICAL RIDGE (STR) POSITIONED
TO THE EAST WITH A STRONGER STR ENTRENCHED TO THE SOUTH.

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T5.0 - 90 KTS
   KNES: T5.0 - 90 KTS
   CIMSS SATCON: 87 KTS AT 070258Z
   CIMSS ADT: 92 KTS AT 070530Z
   CIMSS AIDT: 87 KTS AT 070530Z
   CIMSS DPRINT: 92 KTS AT 070500Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 5-10 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: STRONG POLEWARD

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 03P IS FORECAST TO INTENSIFY THROUGH TAU 24
TO A PEAK INTENSITY OF 105 KNOTS WITH A SLOW SOUTH-SOUTHWESTWARD
TRACK ALONG THE WEAK EASTERN STR. AFTER TAU 24, TC 03P WILL TRACK
SOUTHWESTWARD TO WESTWARD AS THE STEERING INFLUENCE TRANSITIONS TO 
THE MORE DOMINANT STR TO THE SOUTH. AFTER TAU 24, ENVIRONMENTAL 
CONDITIONS ARE EXPECTED TO DEGRADE AS THE SYSTEM INTERACTS WITH AN 
APPROACHING UPPER-LEVEL SHORT-WAVE TROUGH. VERTICAL WIND SHEAR (VWS) 
WILL INCREASE FROM 20 KNOTS AT TAU 24 TO 30 KNOTS BY TAU 60. THE 
070000Z HAFS-A RUN ALSO INDICATES SIGNIFICANT DRY AIR ASSOCIATED WITH 
THE TROUGH WILL ENTRAIN INTO THE NORTHERN REGION OF THE SYSTEM, WHICH
WILL SERVE TO STEADILY WEAKEN THE SYSTEM THROUGH TAU 96. AFTER TAU
96, HAFS-A INDICATES A GRADUAL RE-MOISTENING OF THE CORE, WHICH,
ALONG WITH DECREASING VWS, WILL ALLOW THE SYSTEM TO MAINTAIN
INTENSITY OR PERHAPS INTENSIFY SLIGHTLY BY TAU 120.   

MODEL DISCUSSION: THE BULK OF THE NUMERICAL MODEL GUIDANCE REMAINS
IN FAIR AGREEMENT SUPPORTING THE JTWC FORECAST TRACK WITH MEDIUM
CONFIDENCE. SOME OF THE DETERMINISTIC MODELS HAVE STRUGGLED THUS
FAR WITH INCONSISTENT, UNREALISTIC FORECAST TRACKS, SPECIFICALLY
GALWEM AND THE UKMET ENSEMBLE MEAN. THESE TWO MODELS ARE THE
PRIMARY OUTLIERS AND INDICATE VERY SLOW TRACKS ALONG THE NORTHERN
PORTION OF THE AIDS ENVELOPE. WITH THE EXCEPTION OF GALWEM AND THE 
UKMET ENSEMBLE MEAN, CROSS-TRACK SPREAD VALUES RANGE FROM 110 NM TO
120 NM FROM TAU 72 TO TAU 120. THERE IS SOME UNCERTAINTY IN THE
INTENSITY FORECAST DUE TO THE POTENTIAL FOR EYE FORMATION OVER THE
NEXT DAY AND SIGNIFICANTLY HIGHER PEAK INTENSITIES. THE 061800Z
COAMPS-TC ENSEMBLE IS NOT HOT ON RAPID INTENSIFICATION (RI) WITH 10
TO 20 PERCENT RI PROBABILITIES THROUGH TAU 36. ADDITIONALLY, NONE
OF THE MORE RELIABLE RI AIDS ARE TRIGGERING AT THIS TIME.         

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