MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (WUTIP) WARNING NR 03// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 02W (WUTIP), LOCATED APPROXIMATELY 844 NM SOUTHEAST OF ANDERSEN AFB, HAS TRACKED WESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A CONSOLIDATING SYSTEM WITH IMPROVED DEEP CONVECTIVE BANDING OVER THE NORTHERN AND WESTERN SEMICIRCLES OF A LOW-LEVEL CIRCULATION. A 191901Z SSMIS 91GHZ MICROWAVE IMAGE (MI) DEPICTS DEEP CONVECTIVE BANDING WRAPPING INTO A DEFINED LOW-LEVEL CIRCULATION CENTER FROM THE NORTH AND WEST. BASED ON MI, THERE IS FAIR CONFIDENCE IN THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSED AT 35 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T2.0 TO 2.5 (30 TO 35 KNOTS FROM RJTD AND PGTW, RESPECTIVELY). ENVIRONMENTAL CONDITIONS ARE VERY FAVORABLE WITH LOW TO MODERATE VERTICAL WIND SHEAR ALONG WITH GOOD EQUATORWARD AND POLEWARD OUTFLOW, WARM SST (29 TO 30C) AND HIGH OCEAN HEAT CONTENT VALUES. TS 02W IS CURRENTLY TRACKING WESTWARD ALONG THE SOUTHEASTERN PERIPHERY OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH AND NORTHWEST. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THROUGH TAU 72, TS 02W IS EXPECTED TO TRACK WESTWARD TO WEST- NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED STR ENTRENCHED TO THE NORTH. DUE TO THE VERY FAVORABLE ENVIRONMENTAL CONDITIONS, THE SYSTEM IS FORECAST TO INTENSIFY RAPIDLY TO 100 KNOTS BY TAU 72. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A SPREAD OF 120NM AT TAU 72. C. IN THE EXTENDED PERIOD, UNCERTAINTY INCREASES SIGNIFICANTLY WITH A BIFURCATION IN THE MODEL GUIDANCE. GFS, GFS ENSEMBLE, AFUM, EGRR, JGSM AND NAVGEM INDICATE A RECURVE SCENARIO NEAR GUAM, WHICH APPEARS UNLIKELY AS THE SYSTEM PUSHES THROUGH A SUBTROPICAL RIDGE WITHOUT AN ASSOCIATED SHORTWAVE TROUGH. ECMF AND EEMN INDICATES A FLATTER TRACK MUCH FURTHER TO THE SOUTHWEST WITH A WEST- NORTHWESTWARD TO NORTHWESTWARD TRAJECTORY. THE JTWC OFFICIAL FORECAST FAVORS A NON-RECURVE SCENARIO CLOSER TO THE ECMWF SOLUTION DUE TO THE LACK OF A MIDLATITUDE RECURVE MECHANISM (DEEP SHORTWAVE TROUGH AND ASSOCIATED FRONTAL SYSTEM), AND PRESENCE OF A STRONG STR. TS 02W IS FORECAST, HOWEVER, TO INTENSIFY TO 105 KNOTS AS IT SKIRTS SOUTH OF GUAM, AND MAY STILL PRODUCE GALE-FORCE SUSTAINED WINDS AND ISOLATED GUSTS NEAR 50 KNOTS OVER GUAM. OVERALL, CONFIDENCE REMAINS LOW DUE TO THE BIFURCATION IN THE NUMERICAL GUIDANCE.// NNNN NNNN