WDPN31 PGTW 141500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 15W (KALMAEGI) WARNING NR 16//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 15W (KALMAEGI), LOCATED APPROXIMATELY 203 NM NORTH-
NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD
AT 18 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED 
SATELLITE IMAGERY (EIR) SHOWS THE CENTRAL DENSE OVERCAST FEATURE AND 
DEEP CONVECTIVE BANDING HAS WARMED AND STARTED TO DECREASE IN SIZE 
AND SYMMETRY AS THE SYSTEM HAS MADE LANDFALL ACROSS NORTHERN LUZON. 
A 141132Z SSMIS MICROWAVE IMAGE SHOWS THE LOW LEVEL CIRCULATION 
CENTER (LLCC) HAS STARTED TO BECOME POORLY DEFINED WHILE THE TIGHTLY 
CURVED BANDING PREVIOUSLY OBSERVED HAS BECOME FRAGMENTED. THERE IS 
NOW ONLY FAIR CONFIDENCE IN THE INITIAL POSITION AND TRACK MOTION 
DUE TO THE LLCC NOW BEING OVERLAND AND POORLY DEFINED. THE INITIAL 
INTENSITY REMAINS ASSESSED AT 70 KNOTS BASED ON DVORAK INTENSITY 
ESTIMATES THAT RANGE FROM 65 TO 77 KNOTS, WHILE A PREVIOUS 140845Z 
SSMIS SHOWED IMPROVED STRUCTURE AS A DEVELOPING EYEWALL FEATURE WAS 
OBSERVED JUST PRIOR TO LANDFALL. UPPER-LEVEL ANALYSIS REVEALS AN 
UNCHANGED ENVIRONMENT CHARACTERIZED BY MODERATE (15 TO 25 KNOTS) 
NORTHEASTERLY VERTICAL WIND SHEAR (VWS) THAT CONTINUES TO HAMPER THE 
SYSTEM WHILE STRONG EQUATORWARD OUTFLOW AND THE MOTION OF THE SYSTEM 
OFFSETS THE NEGATIVE EFFECTS OF THE VWS. TY 15W IS CURRENTLY 
TRACKING ALONG THE SOUTHERN PERIPHERY OF AN EAST-WEST ORIENTED 
SUBTROPICAL RIDGE (STR) ENTRENCHED TO THE NORTH OF THE SYSTEM.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS 
PROGNOSTIC REASONING MESSAGE.
   B. TY 15W IS FORECAST TO ACCELERATE WEST-NORTHWESTWARD UNDER THE 
STEERING INFLUENCE OF THE STRONG STR THROUGH TAU 72. THE SYSTEM WILL 
CONTINUE TO SLIGHTLY WEAKEN BEFORE RE-EMERGING ACROSS THE SOUTH 
CHINA SEA (SCS) WERE RE-INTENSIFICATION IS EXPECTED DUE TO FAVORABLE 
ENVIRONMENTAL CONDITIONS IN THE SCS. NEAR TAU 48, TY 15W IS FORECAST 
TO WEAKEN AGAIN AS IT APPROACHES AND DRAGS ACROSS THE SOUTHERN COAST 
OF CHINA.
   C. IN THE EXTENDED TAUS, TY 15W IS EXPECTED TO MAINTAIN A 
PREDOMINANTLY WESTWARD TRACK THROUGH THE REMAINDER OF THE FORECAST 
PERIOD AS THE STR REMAINS ENTRENCHED TO THE NORTH. FURTHER WEAKENING 
IS EXPECTED AS THE SYSTEM TRACKS WELL INLAND WITH DISSIPATION 
EXPECTED BY TAU 96. DYNAMIC MODEL GUIDANCE (INCLUDING THE MODEL 
ENSEMBLES) IS IN VERY TIGHT AGREEMENT, THEREFORE, THERE IS HIGH 
CONFIDENCE IN THE JTWC FORECAST TRACK, WHICH IS POSITIONED CLOSE TO 
THE MULTI-MODEL CONSENSUS.//
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