WDPN31 PGTW 241500 
MSGID/GENADMIN/NAVPACMETOCCEN PEARL//JTWC//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 31W (FAXAI) WARNING NR 52//
RMKS/
1. FOR METEOROLOGISTS.
2. PROGNOSTIC REASONING FOR 241200Z9 TO 271200Z2 DEC 01.
   A. TYPHOON (TY) 31W (FAXAI), LOCATED APPROXIMATELY 85 NM NORTH-
NORTHEAST OF AGRIHAN, HAS TRACKED NORTHWARD AT 10 KNOTS DURING THE 
PAST 6 HOURS. THE WARNING POSITION IS BASED ON 241130Z1 ENHANCED 
INFRARED SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED 
ON CURRENT INTENSITY ESTIMATES OF 5.5 (102 KNOTS). 
   B. IMAGERY IS DEPICTING AN EARLY PHASE OF EXTRA TROPICAL 
TRANSITION. ANIMATION IS REVEALING A SIGNIFICANT DECREASE OF DEEP 
CLOUDINESS AND BANDS OVER THE WESTERN QUADRANT. A DRY SLOT IS 
VISIBLE BETWEEN RAINBANDS OVER THE SOUTH QUADRANT AS WELL AS A 
MARKED REDUCTION IN DEEP CONVECTION. A LARGE REGION OF MULTI-LAYER 
CLOUDS NOW EXTENDS OVER THE NORTH QUADRANT. CONFLUENT FLOW BETWEEN 
THE POLEWARD OUTFLOW CHANNEL FROM THE SYSTEM AND THE PFJ IS 
GENERATING A LARGE CIRRUS SHIELD TOWARD THE NORTHEAST. IN ADDITION, 
A LOOP OF THE PAST 3 SSM/I PASSES REVEALS THAT THE DEEP CONVECTION 
HAS ROTATED TO A CONFINED AREA OVER THE NORTH QUADRANT. THE LATEST 
IMAGE ALSO CONFIRMS THAT THE SOUTH QUADRANT IS NOW DEEP CONVECTION 
FREE. THERE IS, OF COURSE, THE USUAL DISPARITY IN HOW NWP HANDLES 
THE EXTRA-TROPICAL TRANSITION. THE UKMET SPECTRAL, AVN, AND GFDN 
INDICATE A COMPLEX TRANSITION (NEW BAROCLINIC LOW DEVELOPMENT ALONG 
A FRONTAL BOUNDARY) BETWEEN THE 36 AND 48 HOUR TIMEFRAME. NOGAPS, 
COAMPS, THE AFWA MESOSCALE (MM5), AND THE JMA GLOBAL AND TYPHOON 
SHOW A COMPOUND TRANSITION (MERGE WITH A BAROCLINIC LOW) BY 48. OUR 
FORECAST IS BASED ON THE LARGER GROUP SIGNIFYING A COMPOUND 
TRANSITION.
   C. A WEAKENING TREND SHOULD CONTINUE THROUGH THE EARLY STAGES OF 
THE TRANSITION AS THE UPPER SOUTHWESTERLIES CREATE HAVOC ON THE 
SYSTEM. LATE IN THE PERIOD, A SLIGHT INTENSIFICATION MAY RESULT 
AFTER THE TRANSITION COMPLETION.
   D. WIND RADII ANALYSIS IS BASED ON MICROWAVE IMAGERY. WIND RADII 
FORECAST THROUGH 36 HOURS IS BASED ON CLIMATOLOGY. FOR GALE AND SEA 
HEIGHT INFORMATION ON XT POSITIONS, REFER TO WWPW31 RJTX BULLETIN.
FORECAST TEAM: ROBERTS/WAUGAMAN/BOSTIC/EDBERG//