WDPN32 PGTW 190300
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 28W
/WARNING NR 21//
RMKS/
1. FOR METEOROLOGISTS.
2. PROGNOSTIC REASONING FOR 190000Z0 TO 240000Z6 OCT 2004.
   A. TYPHOON (TY) 28W (NOCK-TEN), LOCATED APPROXIMATELY 300 NM
SOUTHEAST OF GUAM, HAS TRACKED WESTWARD AT 12 KNOTS OVER THE
PAST 06 HOURS. THE WARNING POSITION IS BASED ON 182330Z7 MULTI-
SPECTRAL SATELLITE IMAGERY. THE WARNING INTENSITY IS BASED ON
SATELLITE CURRENT INTENSITY ESTIMATES OF 77 AND 90 KNOTS. VISIBLE
SATELLITE IMAGERY DEPICTS A RAGGED CLOUD FILLED 9 NM EYE.
   B. TY 28W IS FORECAST TO MOVE WESTWARD ALONG THE SOUTHERN
PERIPHERY OF THE MID-LEVEL STEERING RIDGE LOCATED TO THE NORTH FOR
THE NEXT 06 TO 12 HOURS AND THEN SHIFT TO A MORE WEST-NORTHWESTERLY
TRACK IN RESPONSE TO A SHIFT IN THE SUBTROPICAL RIDGE. AS THE RIDGE
REACTS TO A TROUGH THAT WILL BE MOVING NORTHEAST OVER JAPAN AND THE
PASSAGE OF TY 27W THE RIDGE WILL SHIFT EASTWARD WHICH WILL ALLOW TY
28W TO RECURVE AND TRACK NORTHWEST TOWARDS JAPAN. THE AVAILABLE
DYNAMIC AIDS CONSISTING OF TCLAPS, COAMPS, MM5, NCEP GFS, GFDN, 
UKMET, NOGAPS, JGSM, JTYM, AND WBAR ARE IN GOOD AGREEMENT OUT TO 
TAU 72. THIS FORECAST IS BASED ON A CONSENSUS OF ALL AVAILABLE DY-
NAMIC AIDS.
   C. TY 28W IS EXPECTED TO CONTINUE INTENSIFYING AT A NEAR CLIMA-
TOLOGICAL RATE THROUGH THE MID-PERIOD WITH A SLIGHT WEAKENING IN
THE LATER TAUS DUE TO EASTERLY SHEAR. CURRENTLY TY 28W IS BEING 
SUPPRESSED IN THE NORTHEAST QUADRANT DUE TO AN UPPER LEVEL LOW.
THE POTENTIAL EXISTS FOR A POLEWARD OUTFLOW CHANNEL TO DEVELOP IF
THE UPPER LEVEL LOW MOVES AWAY FROM TY 28W. 
   D. CURRENT WIND RADII ARE BASED ON MICROWAVE IMAGERY. FORECAST WIND
RADII ARE BASED ON CLIMATOLOGY FOR AN AVERAGE SIZED SYSTEM.
   E. THE EXTENDED FORECAST HAS TY 28W TRACKING ALONG THE SOUTHWEST
PERIPHERY OF THE MID-LEVEL STEERING RIDGE TO THE NORTH AND EAST
WITH A SLIGHT DECREASE IN INTENSITY DUE TO EASTERLY SHEAR. AIDS
ARE IN POOR AGREEMENT WITH THE TRACK IN THE EXTENDED TAUS WITH GFDN
AND NCEP GFS LOOKING FOR A STRONGER RIDGE AND WITH UKMET AND NOGAPS 
FORECASTING A SHORTWAVE TROUGH TO WEAKEN THE RIDGE AND TRACK TY 
28W MORE POLEWARD.
FORECAST TEAM: KENDALL/MENEBROKER/TINOCO/FUNK/JAYKOSKI//