WDPN31 PGTW 030300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 22W (HAGUPIT) WARNING NR 09// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 22W (HAGUPIT), LOCATED APPROXIMATELY 186 NM SOUTHEAST OF YAP, HAS TRACKED WEST-NORTHWESTWARD AT 18 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A TIGHTLY WRAPPED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH A PERSISTENT CENTRAL DENSE OVERCAST FEATURE THAT HAS INCREASED IN SIZE AND SYMMETRY OVER THE PAST SIX HOURS. A 022341Z AMSU-B MICROWAVE IMAGE REVEALS INCREASED TIGHTLY CURVED BANDING AROUND THE LLCC. THE CURRENT POSITION IS BASED ON THE MSI ANIMATION, PGTW AND RJTD SATELLITE POSITION FIXES, AND THE MICROWAVE IMAGE WITH GOOD CONFIDENCE. THE INITIAL INTENSITY HAS BEEN INCREASED TO 90 KNOTS BASED ON DVORAK INTENSITY ESTIMATES FROM PGTW AND RJTD. UPPER-LEVEL ANALYSIS INDICATES TY 22W REMAINS IN A FAVORABLE ENVIRONMENT WITH LOW VERTICAL WIND SHEAR (VWS) AND EXCELLENT RADIAL OUTFLOW AS EVIDENT ON THE WATER VAPOR IMAGERY. TY HAGUPIT IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) ANCHORED TO THE NORTH. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THROUGH THE NEXT 72 HOURS, TY 22W IS EXPECTED TO CONTINUE WEST- NORTHWESTWARD ALONG THE STR AND SHOULD BEGIN TO SLOW DOWN AS A DEEP MIDLATITUDE TROUGH DEEPENS ACROSS JAPAN AND SLIGHTLY RE-ORIENTS THE STR. FAVORABLE SEA SURFACE TEMPERATURES, ALONG WITH CONTINUALLY FAVORABLE UPPER-LEVEL CONDITIONS, WILL ALLOW THE SYSTEM TO FURTHER INTENSIFY AND IS EXPECTED TO REACH SUPER TYPHOON STATUS BY TAU 48. AFTER TAU 48, VWS IS FORECAST TO INCREASE AS A NORTHEAST SURGE EVENT BEGINS WHICH WILL INDUCE A SLIGHT WEAKENING TREND. DYNAMIC GUIDANCE REMAINS IN GOOD AGREEMENT THROUGH THIS PORTION OF THE FORECAST PERIOD AS THE TRACK SPREAD HAS DECREASED TO NEAR 100 NM BY TAU 72. THIS IS DUE TO A DISAGREEMENT ON THE ORIENTATION OF THE STR IN RESPONSE TO THE AFOREMENTIONED MID-LATITUDE TROUGH AND IN THE STRENGTH OF THE SYSTEM AS PROCEEDS TO THE WEST-NORTHWEST. C. PAST TAU 72, A COL REGION ALONG THE STR AXIS IS EXPECTED TO DEVELOP WHICH WILL RESULT IN AN OVERALL WEAK STEERING ENVIRONMENT WHILE THE NORTHEAST SURGE EVENT IS FORECAST TO KEEP THE SYSTEM FROM GAINING LATITUDE. THIS WILL DRIVE TY 22W ON AN OVERALL SLOW WESTWARD DRIFT WHILE INCREASING VWS FROM THE SURGE EVENT FURTHER WEAKENS THE SYSTEM. NUMERIC MODEL GUIDANCE, ALONG WITH ENSEMBLE DATA, REMAIN WIDELY SPREAD WITH SOLUTIONS THAT CONTINUE TO RANGE FROM A SLOW POLEWARD TURN TO A FAST STRAIGHT RUN TRACK INTO THE CENTRAL PHILIPPINE ISLANDS. DUE TO THIS, THERE IS OVERALL LOW CONFIDENCE IN THE FORECAST TRACK WHICH IS POSITIONED CLOSE TO MULTI-MODEL CONSENSUS AND IS CONSISTENT WITH THE PREVIOUS FORECAST.// NNNN