WDPN31 PGTW 280300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 04W (MAYSAK) WARNING NR 05// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 04W (MAYSAK), LOCATED APPROXIMATELY 694 NM EAST-SOUTHEAST OF ANDERSEN AFB, GUAM HAS TRACKED WESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A TIGHTLY CONSOLIDATED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH A CENTRAL DENSE OVERCAST FEATURE AND DEEP CURVED CONVECTIVE BANDING WRAPPING IN FROM THE NORTHERN PERIPHERY. A 272122Z SSMIS 37GHZ MICROWAVE IMAGE SHOWS THE DEEP CURVED CONVECTIVE BANDING ALONG THE NORTHERN PERIPHERY OF THE SYSTEM WRAPPING INTO A DEVELOPING MICROWAVE EYE FEATURE. THE INITIAL POSITION IS BASED ON THE SSMIS MICROWAVE IMAGE AND POSITION FIXES FROM ALL AGENCIES WITH GOOD CONFIDENCE. THE CURRENT INTENSITY OF 45 KNOTS IS BASED ON DVORAK INTENSITY ESTIMATES OF T3.0 (45 KNOTS) FROM PGTW AND KNES. TS 04W IS LOCATED IN A FAVORABLE UPPER LEVEL ENVIRONMENT WITH LOW TO MODERATE (10-15 KNOT) EASTERLY VERTICAL WIND SHEAR (VWS) OFFSET BY STRONG DIVERGENCE ALOFT. TS MAYSAK IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE DEEP LAYERED SUB-TROPICAL RIDGE (STR) TO THE NORTH. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 04W WILL CONTINUE TO TRACK WESTWARD UNDER THE INFLUENCE OF THE DOMINANT STEERING STR THROUGH TAU 72. LOW VWS, EXCELLENT OUTFLOW, AND SEA SURFACE TEMPERATURES ABOVE 29 CELSIUS ARE EXPECTED TO PERSIST, RESULTING IN STEADY INTENSIFICATION. C. AFTER TAU 72, TS MAYSAK WILL TURN TO THE WEST-NORTHWEST AS THE STEERING STR WEAKENS DUE TO A PASSING SHORTWAVE TROUGH TO THE NORTH. TS 04W WILL CONTINUE TO INTENSIFY REACHING A PEAK OF 115 KNOTS BY TAU 96. BEYOND TAU 96, TS MAYSAK WILL MAINTAIN INTENSITY AS REDUCED OUTFLOW DUE TO THE WEAKENING STR INHIBITS FURTHER INTENSIFICATION. DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT, LENDING TO HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN