WDPS31 PGTW 130900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03P (JASPER) WARNING NR 034//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 15.7S 145.8E
   INITIAL INTENSITY: 60 KTS
   GEOGRAPHIC REFERENCE: 72 NM NORTH OF CAIRNS, AUSTRALIA
   MOVEMENT PAST 6 HOURS: WESTWARD AT 06 KTS
   SIGNIFICANT WAVE HEIGHT: 30 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A MORE
COMPACT TROPICAL CYCLONE WITH SPIRAL BANDING WRAPPING TIGHTER AND
COMPLETELY AROUND BOTH NORTHERN AND SOUTHERN SEMICIRCLES THAT IS
ABOUT TO MAKE LANDFALL OVER THE EASTERN COAST OF CAPE YORK
PENINSULA. THE SYSTEM HAS ALSO MAINTAINED A BANDING EYE WITH THE
COLDEST CLOUD TOPS (-55 TO -65 DEGREES CELSIUS) AROUND THE EYEWALL.
THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE
BANDING EYE FEATURE AND A DEFINED CIRCULATION FEATURE IN A
COMPOSITE RADAR LOOP. THE INITIAL INTENSITY OF 60 KTS IS ALSO
PLACED WITH HIGH CONFIDENCE BASED ON THE HIGH END OF AGENCY AND
AUTOMATED DVORAK ESTIMATES AND SUPPORTED BY NEARBY SURFACE
OBSERVATIONS INCLUDING GUSTS TO 62KTS AT MOSSMAN, AUSTRALIA.
ANALYSIS INDICATE A FAVORABLE ENVIRONMENT WITH LOW VWS, WARM SST
AND IMPROVED POLEWARD OUTFLOW OFFSET BY DRY AIR INTRUSION AND
IMMINENT LANDFALL.

INITIAL WIND RADII BASIS: PERSISTENCE.

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE TO THE SOUTHEAST. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T4.0 - 65 KTS
   KNES: T3.5 - 55 KTS
   CIMSS SATCON: 41 KTS AT 130425Z
   CIMSS ADT: 37 KTS AT 130530Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 0-5 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: MODERATE EASTWARD

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TROPICAL CYCLONE 03P (JASPER) WILL CONTINUE
WESTWARD UNDER THE STEERING STR TO THE SOUTHEAST, MAKE LANDFALL BY
TAU 06, AND TRACK INLAND THROUGH CAPE YORK. ENVIRONMENTAL
CONDITIONS WILL RAPIDLY DETERIORATE WITH LAND INTERACTION,
INCREASED DRY AIR INTRUSION FROM THE AUSTRALIAN OUTBACK, AND
INCREASING VWS CAUSING THE SYSTEM TO DISSIPATE BY TAU 36. THE
REMNANTS OF TC JASPER WILL EXIT INTO THE GULF OF CARPENTARIA BEFORE
TAU 48 AND TRACK MORE WEST-NORTHWESTWARD AS A SECONDARY STR
ANCHORED OVER CENTRAL AUSTRALIA ASSUMES STEERING. 

MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT WITH THE
MAIN PACK GRADUALLY AND EVENLY SPREADING OUT TO 82NM AT TAU 36. A
NOTABLE OUTLIER IS NAVGEM THAT CONTINUES TO SIGNIFICANTLY AND
UNREALISTICALLY STRAY FROM THE MAIN PACK SOUTHWESTWARD INTO THE
RIDGE. THERE IS A HIGH CONFIDENCE IN THE JTWC TRACK FORECAST THAT
IS LAID JUST TO THE NORTH OF THE MODEL CONSENSUS TO OFFSET NAVGEM.
THERE IS ONLY MEDIUM CONFIDENCE IN THE INTENSITY FORECAST DUE TO
THE UNCERTAINTIES OF LAND INTERACTION. 

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