WDPN31 PGTW 101500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 03W
/WARNING NR 18//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
   A. TROPICAL STORM (TS) 03W, AERE, LOCATED APPROXIMATELY 330 NM
SOUTHWEST OF KADENA AB, OKINAWA, HAS TRACKED NORTHEASTWARD AT 19
KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE
IMAGERY (MSI) INDICATES TS 03W IS ACCELERATING IN ITS TURN AROUND 
THE 
NORTHWEST SIDE OF A MID TO UPPER LEVEL STEERING RIDGE. ANIMATED 
WATER VAPOR IMAGERY SHOWS A WELL DEVELOPED POLEWARD OUTFLOW 
CHANNEL IS SUSTAINING SYSTEM CONVECTION OVER THE NORTHEAST QUADRANT, 
WHILE AN UPPER LEVEL TROUGH ENCROACHING ON THE WESTERN FLANK OF THE 
SYSTEM SUPPRESSES CONVECTION OVER THE WESTERN SEMI-CIRCLE. TWO 
RECENT MICROWAVE PASSES COMBINED WITH INFRARED ANIMATION ALSO REVEAL 
A DISTINCT MOISTURE BOUNDARY OVER THE EASTERN HALF OF THE STORM, 
WHICH IS IMPEDING INTENSIFICATION. TS 03W EXISTS IN A HIGHLY 
DIFFLUENT UPPER LEVEL ENVIRONMENT WITH APPROXIMATELY 15 KNOTS OF 
VERTICAL WIND SHEAR. THE CURRENT INTENSITY 
ANALYSIS IS BASED ON DVORAK ESTIMATES OF 35 KNOTS FROM PGTW AND 
KNES. THE LOW LEVEL CIRCULATION CENTER (LLCC) IS PARTIALLY EXPOSED. 
A 100922Z 37GHZ SSMIS IMAGE INDICATES THAT MOST OF THE SYSTEM 
CONVECTION IS BEING DISPLACED EASTWARD OF THE LLCC. A 100922Z 
CORIOLIS IMAGE SHOWS EXTENSIVE CURVED BANDING OVER THE WESTERN HALF 
OF THE SYSTEM. THE TWO MICROWAVE PASSES IN TANDEM WITH INFRARED 
ANIMATION GIVE GOOD CONFIDENCE TO THE POSITION FIX. TS 03W IS 
TRACKING THROUGH MARGINALLY FAVORABLE (26-28 CELSIUS)SEA SURFACE 
TEMPERATURES (SST). 
3. FORECAST REASONING.
   A. NO SIGNIFICANT CHANGE TO FORECAST PHILOSOPHY.
   B. ENHANCED POLEWARD OUTFLOW AND FAVORABLE DIFFLUENCE ALOFT WILL 
ENABLE 
TS 03W TO MAINTAIN INTENSITY OVER THE NEXT 24 HOURS. THE SYSTEM WILL 
CONTINUE STEERING ALONG THE NORTHWESTERN PERIPHERY OF THE SUB-
TROPICAL RIDGE, WHICH IS WEAKENING WHILE RECEDING SOUTHEAST. MODEL 
GUIDANCE IS IN EXCELLENT AGREEMENT THROUGH THE FIRST 24 HOURS. AFTER 
TAU 24, INCREASING VERTICAL WIND SHEAR AND FALLING SST WILL COMBINE 
TO WEAKEN THE SYSTEM. AFTER TS 03W PASSES OKINAWA, IT WILL BEGIN 
INTERACTION WITH THE BAROCLINIC ZONE AND STEADILY WEAKEN ALONG A 
TRACK WELL SEAWARD OF THE MAIN ISLANDS OF JAPAN. EXTRA-TROPICAL 
TRANSITION SHOULD BE COMPLETED BY TAU 60. MODEL INTENSITY GUIDANCE 
IS IN GOOD AGREEMENT WITH A GRADUAL WEAKENING TREND, BUT SOME 
DISPARITY IN TRACK FORECAST EXISTS AFTER TAU 24. THE EGRR AND 
JAPANESE MODELS TRACK THE SYSTEM CLOSER TO JAPAN  THAN THE OTHER 
CONSENSUS MODELS, WITH EGRR FORECASTING A LAND STRIKE OVER CENTRAL 
HONSHU NEAR TAU 48. GIVEN THE ZONAL NATURE AND RELATIVE VIGOR OF THE 
MID-LATITUDE WESTERLIES, THE EGGR/JGSM SCENARIO IS DOUBTFUL. AS A 
RESULT OF DISCOUNTING THE INFLUENCE OF EGGR AND JGSM ON CONSENSUS, 
THE JT FORECAST  STAYS EQUATORWARD OF CONSENSUS.//
NNNN