WDPN31 PGTW 021500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 13W (SOUDELOR) WARNING NR 14// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 13W (SOUDELOR), LOCATED APPROXIMATELY 8 NM SOUTHEAST OF SAIPAN, HAS TRACKED WEST-NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A RAPIDLY CONSOLIDATING SYSTEM WITH AN 8-NM EYE. A 020918Z SSMIS IMAGE SHOWS A NEAR-COMPLETE EYEWALL WITH MULTIPLE SPIRAL BANDS WRAPPING INTO THE CENTER. BASED ON GUAM RADAR IMAGERY AND FIXES, THERE IS GOOD CONFIDENCE IN THE CURRENT POSITION AND RECENT TRACK MOTION. TY 13W IS CURRENTLY CROSSING DIRECTLY OVER SAIPAN; SURFACE OBSERVATIONS FROM SAIPAN, THUS FAR, INDICATE MAXIMUM SUSTAINED WINDS OF 47 KNOTS GUSTING TO 79 KNOTS. THE CURRENT INTENSITY HAS BEEN INCREASED TO 90 KNOTS BASED ON DVORAK INTENSITY ESTIMATES OF T5.0 (90 KNOTS) FROM RJTD AND PGTW. ENVIRONMENTAL CONDITIONS REMAIN CONDUCIVE FOR RAPID DEVELOPMENT WITH EXCELLENT RADIAL OUTFLOW AIDED BY THE TUTT CELL TO THE NORTHEAST, LOW (5-10 KNOTS) VERTICAL WIND SHEAR (VWS), SEA SURFACE TEMPERATURES (SSTS) FROM 30 TO 31 CELSIUS, AND HIGH OCEAN HEAT CONTENT. TY SOUDELOR IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED SUB-TROPICAL RIDGE (STR) TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 13W IS FORECAST TO TRACK GENERALLY WEST-NORTHWESTWARD THROUGHOUT THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF THE WELL-ESTABLISHED STR. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN CONDUCIVE FOR TY 13W TO UNDERGO RAPID INTENSIFICATION OVER THE NEXT 36 TO 48 HOURS. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 72 WITH A SPREAD OF 175 NM AT TAU 72. BASED ON THE OVERALL STABILITY OF THE MULTI-MODEL CONSENSUS AND THE BULK OF MODEL GUIDANCE, THERE IS HIGH CONFIDENCE DURING THIS PORTION OF THE FORECAST. C. IN THE EXTENDED FORECAST, THE INTENSIFICATION RATE WILL DECREASE DUE TO REDUCED OCEAN HEAT CONTENT AND A SLIGHT INCREASE IN VWS TO MODERATE LEVELS. SSTS ARE EXPECTED TO DECREASE SLIGHTLY NEAR TAU 72 AND THEN INCREASE AGAIN BY THE END OF THE FORECAST PERIOD AS TS 13W NEARS TAIWAN. THIS SHOULD ALLOW TY SOUDELOR TO OFFSET SOME OF THE AFOREMENTIONED NEGATIVE EFFECTS. MODEL TRACK SOLUTIONS ARE NOW IN TIGHT AGREEMENT IN THE EXTENDED TAUS. THE JTWC TRACK IS POSITIONED VERY CLOSE TO THE PREVIOUS FORECAST AND, DUE TO THE CONTINUED AGREEMENT IN THE DYNAMIC MODEL GUIDANCE, THERE IS HIGH CONFIDENCE IN THE OVERALL JTWC TRACK FORECAST.// NNNN