WDPN32 PGTW 252100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 21W (MOLAVE) WARNING NR 008//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 21W (MOLAVE), LOCATED APPROXIMATELY 96 NM SOUTH-
SOUTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT 17 KNOTS 
OVER THE PAST SIX HOURS. TY 21W HAS RAPIDLY INTENSIFIED 35 KNOTS 
OVER THE PAST 24 HOURS FROM 40 KNOTS AT 24/18Z TO THE CURRENT 
INTENSITY OF 75 KNOTS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY 
DEPICTS A CONSOLIDATING SYSTEM WITH AN EXPANDING CENTRAL DENSE 
OVERCAST FEATURE. THE IMPROVED CONVECTIVE STRUCTURE IS CLEARLY 
EVIDENT IN A 251840Z GMI 89GHZ IMAGE, WHICH SHOWS SPIRAL BANDING AND 
A COMPACT EYEWALL SURROUNDING A MICROWAVE EYE FEATURE. THE INITIAL 
INTENSITY IS ASSESSED AT 75 KTS BASED ON THE HIGH END OF DVORAK 
INTENSITY ESTIMATES RANGING FROM T4.0-4.5 (65-77 KNOTS) AND A 
251740Z ADT ESTIMATE OF 4.6 (79 KNOTS). ENVIRONMENTAL ANALYSIS 
REVEALS OVERALL FAVORABLE CONDITIONS CHARACTERIZED BY ROBUST 
EQUATORWARD OUTFLOW, LOW TO MODERATE (15-20 KTS) VERTICAL WIND 
SHEAR, AND WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES. TY 21W IS 
TRACKING WESTWARD ALONG THE SOUTHERN PERIPHERY OF A SUBTROPICAL 
RIDGE (STR) POSITIONED TO THE NORTH.
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE 
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TY 21W IS FORECAST TO TRACK WESTWARD TO WEST-NORTHWESTWARD 
THROUGH TAU 48 UNDER THE STEERING INFLUENCE OF THE DEEP-LAYERED 
SUBTROPICAL RIDGE ENTRENCHED TO THE NORTH. AFTER A BRIEF PERIOD OF 
WEAKENING AS THE SYSTEM TRACKS OVER PANAY ISLAND, TY 21W SHOULD RE-
INTENSIFY TO A PEAK INTENSITY OF 95 KNOTS BY TAU 24. THE 25/12Z 
COAMPS-TC ENSEMBLE INDICATES HIGH POTENTIAL FOR A PEAK OF 90-100 
KNOTS WITH A LOW PROBABILITY OF 105 KNOTS. AFTER TAU 48, TY 21W WILL 
GRADUALLY WEAKEN AS IT APPROACHES EASTERN VIETNAM WITH LANDFALL 
EXPECTED NEAR TAU 60. MORE SIGNIFICANT WEAKENING WILL OCCUR AFTER 
TAU 60 AS THE SYSTEM TRACKS INLAND. NUMERICAL MODEL GUIDANCE REMAINS 
IN TIGHT AGREEMENT WITH A 90NM SPREAD IN SOLUTIONS AT TAU 60.     
   C. IN THE EXTENDED RANGE, TY 21W WILL WEAKEN RAPIDLY AS IT TRACKS 
WESTWARD OVER MOUNTAINOUS TERRAIN WITH DISSIPATION OVER LAND 
EXPECTED BY TAU 96. WITH THE EXCEPTION OF JGSM (A SOUTHERLY 
OUTLIER), NUMERICAL MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT 
THROUGH TAU 96, LENDING OVERALL HIGH CONFIDENCE IN THE JTWC FORECAST 
TRACK WHICH IS PLACED NEAR THE MULTI-MODEL CONSENSUS.//
NNNN