WDPN31 PGTW 171500
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 02W WARNING NR 36//
RMKS/
1. FOR METEOROLOGISTS.
2. PROGNOSTIC REASONING FOR 171200Z TO 190000Z MAY 2006.
   A. TYPHOON (TY) 02W (CHANCHU), LOCATED APPROXIMATELY 130 NM
EAST OF HONG KONG, HAS TRACKED NORTH-NORTHEASTWARD AT 13 KNOTS
OVER THE PAST 06 HOURS. ANIMATED SATELLITE IMAGERY AND A 171032Z
SSM/I PASS INDICATE THAT TY 02W HAS BEGUN TRANSITIONING TO AN
EXTRATROPICAL CYCLONE.
   B. TY 02W CONTINUES TO TRACK POLEWARD ALONG THE WESTERN PERI-
PHERY OF A MID-LEVEL STEERING RIDGE CENTERED EAST OF TAIWAN. TY
02W IS FORECAST TO TURN NORTHEASTWARD IN RESPONSE TO A WEAKENESS
DEVELOPING IN THE STEERING RIDGE CAUSED BY AN APPROACHING MID-
LATITUDE TROUGH. TY 02W IS FORECAST TO MAKE LANDFALL EAST OF HONG
KONG BY TAU 12. SATELITE IMAGERY INDICATES THAT TY 02W IS IN THE
INITIAL STAGES OF EXTRATROPICAL TRANSITION; THIS TRANSITION IS
FORECAST TO BE COMPLETE BY TAU 24. THE EXTRATROPICAL CIRCULATION
WILL EXIT CHINA SOUTH OF SHANGHAI BY TAU 36. THE AVAILABLE DYNAMIC
AIDS CONSISTING OF NOGAPS, GFDN, COAMPS, AFWA MM5, NCEP GFS, JGSM,
JTYM, UKMET EGRR, TCLAPS, AND WBAR ARE IN FAIR AGREEMENT WITH THIS
SCENARIO THROUGH TAU 36. VARIATION IN THE WESTWARD EXTENSION OF
THE STEERING RIDGE CAUSE DIFFERENCES IN THE MODEL FORECAST TRACKS.
THIS FORECAST IS BASED ON A CONSENSUS OF ALL AVAILABLE DYNAMIC
AIDS.
   C. TY 02W HAS WEAKENED SLOWLY OVER THE PAST 24 HOURS AS IT
APPROACHES SOUTHERN CHINA. RECENT MICROWAVE IMAGERY REVEALS ERO-
SION OF THE CONVECTION IN THE WESTERN QUADRANTS, AND A BREAKDOWN
OF THE DEEP CONVECTION IN THE EYEWALL. RAPID WEAKENING WILL OCCUR
BY TAU 12 AS THE STORM TRACKS OVER LAND AND COMPLETES EXTRATROPICAL
TRANSITION. 
   D. CURRENT WIND RADII ARE BASED ON A 171032Z SSM/I PASS. FORE-
CAST WIND RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE- TO LARGE-
SIZED SYSTEM.
3. FORECAST TEAM: ALPHA//
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