WDPN31 PGTW 302100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 22W (GONI) 
WARNING NR 012//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   SUPER TYPHOON (STY) 22W (GONI), LOCATED APPROXIMATELY 
520 NM EAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-
SOUTHWESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED
ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A COMPACT,
POWERFUL SYSTEM WITH A WELL DEFINED 7 NM EYE. THE INITIAL 
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE WELL 
DEFINED EYE FEATURE IN THE EIR LOOP. THE INITIAL INTENSITY 
OF 155 KTS IS FURTHER PLACED WITH HIGH CONFIDENCE AND IS 
BASED ON MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF 
T7.5 (155 KTS, PGTW AND RJTD). THIS IS ABOVE ADVANCED
DVORAK TECHNIQUE CURRENT INTENSITY ESTIMATES OF T7.0 (140
KTS) AND A 301712Z CIMSS SATELLITE CONSENSUS INTENSITY OF 
122 KTS, WHICH ARE LIKELY UNDERESTIMATING THE SYSTEM INTENSITY
DUE TO ITS COMPACT SIZE. ANALYSIS OF THE EYE WALL STRUCTURES 
IN SEVERAL MICROWAVE IMAGES SUGGESTS THAT AN EYE WALL 
REPLACEMENT CYCLE (ERC) HAS BEGUN. DESPITE THIS, THE OVERALL 
CONVECTIVE STRUCTURE AND CLOUD TOP TEMPERATURES ARE IN 
AGREEMENT THAT A WEAKENING PHASE TYPICAL OF ERC HAS NOT
YET COMMENCED. STY GONI HAS CONTINUED TO TRACK ALONG THE
SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) POSITIONED 
OVER SOUTHERN CHINA AND THROUGH AN OVERALL FAVORABLE 
ENVIRONMENT WITH VERY WARM (30 DEG CELSIUS) WATERS, LOW (5-10 
KNOTS) VWS AND ROBUST RADIAL OUTFLOW, ALONG WITH ENHANCED
POLEWARD OUTFLOW. 
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. STY GONI WILL CONTINUE TO TRACK GENERALLY SOUTHWESTWARD
TO SOUTH-SOUTHWESTWARD OVER THE NEXT 24 HOURS. THE ENVIRONMENT
WILL REMAIN OVERALL FAVORABLE FOR DEVELOPMENT, HOWEVER A
GRADUAL WEAKENING IS FORECAST DURING THIS TIME DUE TO THE ERC
AND DECREASING POLEWARD OUTFLOW THAT IS A RESULT OF THE ONGOING
REPOSITIONING OF THE STEERING RIDGE. THIS WEAKENING TREND IS 
EXPECTED TO CONTINUE BETWEEN TAU 24 TO TAU 36 DUE TO INCREASING
VWS AT THIS TIME. STY GONI WILL THEN MAKE LANDFALL ALONG THE
COAST OF LUZON, EAST OF MANILA, SHORTLY AFTER TAU 38 AS A 
SIGNIFICANT TROPICAL CYCLONE WITH AN INTENSITY OF 120 KTS. AS 
THE SYSTEM TRANSITS ACROSS LUZON AND INTO THE SOUTH CHINA SEA 
BY TAU 48, IT WILL FURTHER WEAKEN DUE TO TERRAIN INTERACTION TO 
AN INTENSITY OF 75 KTS. AS THE SYSTEM TRACKS OVER THE SOUTH
CHINA SEA BETWEEN TAU 48 AND 72, IT WILL STEADILY WEAKEN TO AN
INTENSITY OF 60 KTS DUE TO CONTINUED MODERATE TO HIGH (20-30 KTS) 
VWS. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT DURING THIS
INITIAL PORTION OF THE JTWC FORECAST TRACK, WITH A TOTAL SPREAD 
IN ACROSS TRACK MODEL SOLUTIONS OF 150 NM AT TAU 72. SPECIFICALLY
THE NAVGEM TRACK LIES NORTHWARD OF THE OTHER JTWC MULTI-MODEL
CONSENSUS MEMBERS. AS SUCH, THIS INITIAL PORTION OF THE JTWC 
FORECAST IS PLACED SLIGHTLY SOUTHWARD OF THE JTWC MULTI-MODEL 
CONSENSUS WITH OVERALL HIGH CONFIDENCE.
   C. IN THE EXTENDED FORECAST, THE SYSTEM WILL TRACK WESTWARD 
ALONG THE SOUTHERN PERIPHERY OF THE DEEP-LAYER STR POSITIONED TO 
THE NORTH THROUGH THE END OF THE FORECAST, AND MAKE A SECOND 
LANDFALL ALONG THE CENTRAL VIETNAM COAST NEAR TAU 120. THE SYSTEM 
WILL CONTINUE TO WEAKEN UNDER THE INFLUENCE OF MODERATE VWS AND 
CONTINUED ENTRAINMENT OF DRY MID-LEVEL AIR. NUMERICAL MODEL TRACK
GUIDANCE BEGINS TO DIVERGE BETWEEN TAU 96 AND 120 WITH UKMET AND 
NAVGEM SOLUTIONS BRINGING THE SYSTEM CENTER NORTHWARD TOWARDS 
HAINAN, CHINA WHILE OTHERS BRING THE SYSTEM CENTER INTO VIETNAM.
THIS 567 NM SPREAD IN SOLUTIONS BY TAU 120 LENDS ONLY FAIR
CONFIDENCE IN THIS FINAL PORTION OF THE JTWC FORECAST TRACK.//
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