WDPS32 PGTW 020300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 16P (KEVIN) 
WARNING NR 002//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 14.4S 162.8E
   INITIAL INTENSITY: 50 KTS
   GEOGRAPHIC REFERENCE: 374 NM WEST-NORTHWEST OF PORT VILA,
VANUATU
   MOVEMENT PAST 6 HOURS: EAST-SOUTHEASTWARD AT 10 KTS
   SIGNIFICANT WAVE HEIGHT: 25 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A
CONSOLIDATING CIRCULATION WITH TIGHTLY WRAPPING DEEP CONVECTION AND
A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC). A RECENT
012206Z ASCAT-B SCATTEROMETRY PASS REVEALS A SLIGHTLY NORTH-SOUTH
ELONGATED CIRCULATION WITH THE HIGHER WINDS (45-52KTS) SOLELY IN
THE NORTHERN SEMICIRCLE. THE INITIAL POSITION IS PLACED WITH LOW
CONFIDENCE BASED ON THE PARTIALLY OBSCURED NATURE OF THE LLCC IN
MSI AND LACK OF NEW MICROWAVE IMAGERY. THE INITIAL INTENSITY OF 50
KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON AGENCY DVORAK
INTENSITY ESTIMATES AND CIMSS ADT WHICH BOTH INDICATE 45-50KTS.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA 

CURRENT STEERING MECHANISM: TRANSITIONING STEERING INFLUENCE FROM A
NEAR EQUITORIAL RIDGE (NER) TO A SUB-TROPICAL RIDGE (STR) TO THE
EAST-SOUTHEAST. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.0 - 45 KTS
   KNES: T3.0 - 45 KTS
   PHFO: T2.5 - 35 KTS
   NFFN: T3.0 - 45 KTS
   CIMSS ADT: 49 KTS AT 012330Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 15-20 KTS
   SST: 30-31 CELSIUS
   OUTFLOW: STRONG RADIAL

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 16P (KEVIN) IS FORECAST TO MIMIC THE TRACK
OF TC 15P (JUDY). AS THE SYSTEM CONTINUES TO TRANSITION ITS
STEERING INFLUENCE TO THE STR TO THE EAST-SOUTHEAST IT WILL
CONTINUE TRACKING GENERALLY SOUTHEASTWARD OVER THE NEXT 48 HOURS.
DURING THIS TIME, THE SYSTEM WILL BE IN A FAVORABLE ENVIRONMENT
CHARACTERIZED BY WARM SEA SURFACE TEMPERATURES AND VIGOROUS OUTFLOW
ALOFT NEGLIGIBLY AFFECTED BY MODERATE VERTICAL WINDS SHEAR. THESE
FACTORS ARE FORECAST TO STRENGTHEN 16P TO 95 KTS AND LIKELY HIGHER,
EVENTUALLY PEAKING NEAR TAU 60. AS 16P CONTINUES POLEWARD OF THE
STR NEAR TAU 72, VERTICAL WIND SHEAR BEGINS TO CLIMB, DRY AIR
ENTRAINMENT INCREASES AND THE SYSTEM PASSES SOUTH OF THE 26 C
ISOTHERM, THESE FACTORS HERALD THE START OF SUB-TROPICAL TRANSITION
(STT). OVER THE FOLLOWING 24 HOURS, THESE FACTORS CONTINUE TO
INCREASE AND THE SYSTEM WILL CONTINUE TO WEAKEN THROUGH TAU 96
AFTER WHICH TC 16P IS FORECAST TO BE FULLY SUB-TROPICAL.

MODEL DISCUSSION: WITH THE EXCEPTION OF NVGM TO THE NORTH AND HWRF
TO THE SOUTH, NUMERICAL MODELS ARE IN TIGHT AGREEMENT THROUGH THE
FORECAST PERIOD WITH ALL REMAINING MEMBERS CLOSELY FOLLOWING THE
MULTI-MODEL CONSENSUS. FOR THIS REASON THE JTWC FORECAST TRACK IS
PLACED WITH MEDIUM CONFIDENCE. RELIABLE MODEL INTENSITY GUIDANCE IS
IN FAIR AGREEMENT WITH SEVERAL RAPID INTENSIFICATION AIDS AND THE
BULK OF THE MODELS SHOWING SHARP INTENSIFICATION THROUGH TAU 60
AFTER WHICH ALL MEMBERS WEAKEN THE SYSTEM THROUGH THE FORECAST
PERIOD. THE TWO EXCEPTIONS TO THIS TREND ARE HWRF AND GFS WHICH
SHOW A MUCH SLOWER INTENSIFICATION THROUGH TAU 60 AND PEAK NEAR OR
BELOW 85 KTS. FOR THESE REASONS THE JTWC INTENSITY FORECAST IS
PLACED WITH MEDIUM CONFIDENCE.

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