WDPN32 PGTW 142100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 05E (DORA) WARNING NR 
058//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 20.5N 168.4E
   INITIAL INTENSITY: 35 KTS
   GEOGRAPHIC REFERENCE: 125 NM NORTHEAST OF WAKE ISLAND
   MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 09 KTS
   SIGNIFICANT WAVE HEIGHT: 15 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A RAGGED,
SHEARED AND DISORGANIZED SYSTEM, WITH FLARING CONVECTION DISPLACED
TO THE EAST OF A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER
(LLCC). THE PRESENCE OF STRONG TUTT-CELL ONLY A COUPLE HUNDRED
MILES TO THE WEST IS PRODUCING OFFSETTING INFLUENCES ON TROPICAL
STORM (TS) 05E (DORA). FIRST, THE CLOSE PROXIMITY OF THE TUTT IS
INDUCING CONVERGENT AND SUBSIDENT NORTHWESTERLY FLOW ON THE WESTERN
SIDE OF THE SYSTEM. THE DIVERGENT PORTION OF THE TUTT LIES JUST
EAST OF THE LLCC, WHICH IS ENHANCING THE CONVECTIVE DEVELOPMENT ON
THE EASTERN SIDE OF THE SYSTEM. A 141633Z SSMIS 89GHZ MICROWAVE
IMAGE SHOWED THE EXPOSED AND VERY SMALL LLCC, WITH FRAGMENTARY AND
DISORGANIZED CONVECTION DISPLACED TO THE EAST. THE INITIAL POSITION
IS ASSESSED WITH HIGH CONFIDENCE BASED ON COMBINATION OF THE
PARTIALLY EXPOSED LLCC AND AN EXTRAPOLATION OF THE MICROWAVE
IMAGERY. THE INITIAL INTENSITY IS ASSESSED WITH LOW CONFIDENCE,
PRIMARILY BASED ON PERSISTENCE WITH EARLIER SCATTEROMETER DATA
WHICH SHOWED A SMALL REGION OF 35 KNOT WINDS IN THE NORTHEASTERN
QUADRANT. SUBJECTIVE AND OBJECTIVE DVORAK INTENSITY ESTIMATES USING
THE SHEAR METHOD ARE GENERATING INTENSITY ESTIMATES IN AGREEMENT
WITH THE JTWC ASSESSMENT.

INITIAL WIND RADII BASIS: PERSISTENCE WITH EARLIER SCATTEROMETER
DATA 

CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) TO THE EAST. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T3.0 - 45 KTS
   RJTD: T3.0 - 45 KTS
   RCTP: T2.0 - 30 KTS
   CIMSS ADT: 41 KTS AT 141430Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
   VWS: 10-15 KTS
   SST: 28-29 CELSIUS
   OUTFLOW: STRONG POLEWARD
   OTHER FACTORS: CONVERGENT SUBSIDENT FLOW ON THE WESTERN SIDE

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

3. FORECAST REASONING.

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

FORECAST DISCUSSION: TS DORA IS EXPECTED TO SLOWLY TRACK TOWARDS
THE NORTH ALONG THE WESTERN SIDE OF THE STEERING RIDGE, THROUGH THE
MAJORITY OF THE FORECAST PERIOD. A SERIES OF DEEP MID-LATITUDE
TROUGHS ARE EXPECTED TO PASS BY TO THE NORTH OF THE SYSTEM THROUGH
THE NEXT FEW DAYS. THE FIRST OF THESE TROUGHS WILL PASS WITHOUT
MUCH INFLUENCE ON THE SYSTEM. THE SECOND OF THESE TROUGHS WILL ALSO
PASS BY TO THE NORTH BUT HAVE A GREATER IMPACT ON THE SYSTEM.
THROUGH THE NEXT 24 HOURS, THE CLOSE PROXIMITY OF THE TUTT-CELL TO
THE NORTHWEST WILL INDUCE NEGATIVE EFFECTS OF CONVERGENT FLOW ALOFT
AND MODERATE WESTERLY SHEAR, LEADING TO A GENTLE WEAKENING DOWN TO
30 KNOTS. AFTER TAU 24, THE TUTT BEGINS TO SHIFT TO THE SOUTHWEST
WHILE TS DORA MOVES NORTH, AND AT THE SAME TIME THE SECOND TROUGH
PASSES BY TO THE NORTH. THE COMBINED EFFECTS OF THESE PATTERN
SHIFTS WILL LEAD TO IMPROVED UPPER-LEVEL DIVERGENCE, AND DECREASED
SHEAR, SUPPORTING A SPURT OF INTENSIFICATION TO 45 KNOTS BY TAU 72.
AFTER TAU 72, THE THIRD IN THE TRAIN OF UPPER-LEVEL TROUGHS WILL
MOVE IN FROM THE WEST, AND TURN TS DORA ONTO A MORE NORTHEASTWARD
TRACK THROUGH THE REMAINDER OF THE FORECAST PERIOD. AS THE SYSTEM
MOVES INTO THE BASE OF THE MID-LATITUDE TROUGH AND ASSOCIATED JET
FINGER, IT WILL BEGIN EXTRATROPICAL TRANSITION (ETT), WITH
TRANSITION TO A GALE-FORCE LOW PRESSURE AREA BY TAU 120. 

MODEL DISCUSSION: TRACK GUIDANCE IS IN GOOD AGREEMENT ON OVERALL
TRACK SCENARIO, WITH MINIMAL CROSS-TRACK SPREAD THROUGH THE ENTIRE
FORECAST PERIOD. ALONG-TRACK SPREAD INCREASES SHARPLY AFTER TAU 96
AS THE SYSTEM BEGINS ETT, LENDING HIGH CONFIDENCE THROUGH THE FIRST
72 HOURS OF THE FORECAST, TRENDING TO LOW CONFIDENCE THROUGH THE
ETT PHASE. INTENSITY GUIDANCE IS MIXED, WITH THE SHIPS (GFS AND
NAVGEM), ALONG WITH BOTH VERSIONS OF COAMPS-TC INDICATING
INTENSIFICATION FROM THE GET-GO, TO A PEAK AS HIGH AS 60 KNOTS BY
TAU 96. MEANWHILE THE GFS AND HAFS-A SUGGEST NEAR-TERM WEAKENING,
FOLLOWED BY REINTENSIFICATION TO A PEAK AROUND 40-45 KNOTS FOLLOWED
BY WEAKENING DURING ETT. BASED ON THE OVERALL ASSESSMENT OF THE
ENVIRONMENTAL PARAMETERS, THE JTWC FORECAST CLOSELY FOLLOWS THE
HAFS-A FORECAST WITH MEDIUM CONFIDENCE. 

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