WDPS31 PGTW 232100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 07P (SEVEN) WARNING NR 
004//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 17.3S 153.3E
   INITIAL INTENSITY: 35 KTS
   GEOGRAPHIC REFERENCE: 431 NM EAST OF CAIRNS, AUSTRALIA
   MOVEMENT PAST 6 HOURS: WEST-SOUTHWESTWARD AT 03 KTS
   SIGNIFICANT WAVE HEIGHT: 15 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS
FRAGMENTED DEEP CONVECTION CONFINED PRIMARILY TO THE NORTHERN AND
WESTERN PERIPHERIES OF A BROAD CIRCULATION. THE INITIAL POSITION IS
PLACED WITH LOW CONFIDENCE BASED ON MULTI-CHANNEL 231514Z ATMS
IMAGERY. THE INITIAL INTENSITY OF 35 KTS IS ASSESSED WITH MEDIUM
CONFIDENCE BASED ON A CONSENSUS OF SUBJECTIVE DVORAK AND AUTOMATED
INTENSITY ESTIMATES. DEVELOPMENT IS BEING INHIBITED BY THE PRESENCE
OF WEAK TROUGHING ALOFT AND THE BROAD NATURE OF THE LOW-LEVEL
CIRCULATION.

INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK 

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) BUILDING FROM
THE SOUTH AND SOUTHWEST

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T2.5 - 35 KTS
   CIMSS ADT: 35 KTS AT 231730Z
   CIMSS D-PRINT: 32 KTS AT 231800Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
UNFAVORABLE
   VWS: 0-5 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: WEAK WESTWARD
   OTHER FACTORS: WEAK UPPER-LEVEL LOW OVER CIRCULATION

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TC 07P CONTINUES TO TRACK SLOWLY
WEST-SOUTHWESTWARD ALONG AN EXTENSION OF THE STR TO THE SOUTH,
WHICH WILL CONTINUE TO BUILD AND DOMINATE STEERING THROUGH THE
REMAINDER OF THE FORECAST PERIOD. SLOW BUT STEADY INTENSIFICATION
IS ANTICIPATED OVER THE NEXT 36 HOURS AS THE UPPER-LEVEL LOW
CURRENTLY ANALYZED OVER THE LOW-LEVEL CIRCULATION ERODES AND THE
OUTFLOW PATTERN CONSEQUENTLY IMPROVES. LOW VERTICAL WIND SHEAR AND
PASSAGE OVER VERY WARM WATER PRIOR TO LANDFALL WILL ALSO SUPPORT
FURTHER DEVELOPMENT, ALTHOUGH THE BROAD CIRCULATION HAS ONLY
LIMITED TIME TO CONSOLIDATE. THE SYSTEM WILL RAPIDLY WEAKEN AS IT
TRACK INLAND AFTER TAU 36, WITH DISSIPATION ANTICIPATED BY TAU 72.

MODEL DISCUSSION: NUMERICAL MODEL TRACK FORECAST GUIDANCE IS IN
GOOD OVERALL AGREEMENT REGARDING THE FORECAST TRACK, ALTHOUGH
LOW CONFIDENCE IN THE INITIAL POSITION ADDS AN ELEMENT OF NEAR-TERM
UNCERTAINTY. MESOSCALE DYNAMIC MODELS, INCLUDING HAFS AND
COAMPS-TC, AND STATISTICAL-DYNAMICAL SHIPS GUIDANCE ARE IN GOOD
AGREEMENT WITH THE CURRENT FORECAST AND HIGHLY CONSISTENT WITH
EXPECTATIONS FOR AN IMPROVING ENVIRONMENT WITH SLOW CONSOLIDATION
OF THE RELATIVELY BROAD AND DISORGANIZED CIRCULATION. THUS,
CONFIDENCE IN THE INTENSITY FORECAST IS HIGH.

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