MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (WUTIP) WARNING NR 07// RMKS// 1. FOR METEOROLOGISTS. 2. HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 02W (WUTIP), LOCATED APPROXIMATELY 609 NM SOUTHEAST OF ANDERSEN AFB, HAS TRACKED WESTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A SWIFTLY CONSOLIDATING SYSTEM WITH AN IMPROVED CONVECTIVE SIGNATURE, WITH THE CONVECTIVE ACTIVITY OFFSET TOWARDS THE WEST OF THE LLCC. A 201828Z AMSU-B 89GHZ MICROWAVE IMAGE INDICATES DEEP CONVECTIVE BANDING WRAPPING INTO THE DEFINED LLCC, AND SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 60 KNOTS BASED ON A DVORAK INTENSITY ESTIMATE OF T3.5 (55 KNOTS) FROM PGTW AND RJTD AND SATELLITE CONSENSUS ESTIMATE OF 67 KNOTS. TS 02W LIES IN A FAVORABLE UPPER-LEVEL ENVIRONMENT WITH EASTERLY DIFFLUENT FLOW ALOFT AND LOW TO MODERATE EASTERLY (15-20 KNOTS) VWS. SST VALUES (29C) AND HIGH OCEAN HEAT CONTENT VALUES ARE CONDUCIVE FOR FURTHER DEVELOPMENT. TS 02W IS TRACKING WESTWARD UNDER THE STEERING INFLUENCE OF THE LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. HOWEVER, THIS FORECAST BRINGS THE TRACK SLIGHTLY CLOSER TO GUAM AND MORE TOWARDS THE RECURVE SCENARIO, AS ECMWF IS NOW AGREEING WITH THE OTHER MODELS ON A RECURVE OCCURRING BEYOND TAU 96. B. THROUGH TAU 72, TS 02W IS EXPECTED TO TRACK WEST-NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED STR ENTRENCHED TO THE NORTH. THE SYSTEM IS FORECAST TO RAPIDLY INTENSITY UNDER FAVORABLE ENVIRONMENTAL CONDITIONS, REACHING A PEAK OF 105 KNOTS AT TAU 48. THE SYSTEM WILL BEGIN TO SLOWLY WEAKEN THROUGH TAU 72 AS INCREASING VWS OFFSETS STRONG POLEWARD OUTFLOW. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH A SPREAD OF 115NM AT TAU 72. C. BEYOND TAU 72, UNCERTAINTY INCREASES SIGNIFICANTLY, WITH A LARGE SPREAD (289NM) BETWEEN THE ECMWF ON THE WEST AND THE REMAINDER OF THE CONSENSUS MEMBERS ON THE EAST SIDE OF THE ENVELOPE. IN GENERAL THE ECMWF HAS WITH THIS RUN STARTED TO SHIFT OVER TOWARDS THE EAST, COMING MORE IN LINE WITH THE OTHER MODELS IN INDICATING A RECURVE TO THE WEST OF THE MARIANAS BEYOND TAU 96. ECMWF HAS COME INTO BETTER AGREEMENT WITH THE OTHER MODELS, IT REMAINS SIGNIFICANTLY WEST OF THE REMAINDER OF THE GUIDANCE. THE NAVGEM AND EGRR, WHILE STILL RECURVING THE SYSTEM, HAVE MOVED TOWARDS THE WEST WITH THE LAST RUN AND GALWEM HAS NOW SHIFTED TO THE STAIR STEP WESTWARD TRACK THAT ECMWF PREVIOUSLY INDICATED. WITH SUCH A CONFUSED AND CHANGING MODEL PACKAGE, THE JTWC OFFICIAL FORECAST HAS SHIFTED ONLY SLIGHTLY TOWARDS THE EAST AT THIS POINT AND FAVORS THE 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. OVERALL, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST BEYOND TAU 72 DUE TO THE UNCERTAINTY IN THE NUMERICAL GUIDANCE.// NNNN NNNN