WTPN22 PGTW 180600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90W)//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/180152Z SEP 25//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT (WTPN21 PGTW 180200)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
090 NM EITHER SIDE OF A LINE FROM 15.8N 133.5E TO 16.2N 130.1E
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 18 TO 23 KNOTS. METSAT
IMAGERY AT 180600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.8N 133.4E. THE SYSTEM IS MOVING NORTHWESTWARD AT 08
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED 15.3N 
134.1E IS NOW LOCATED 15.8N 133.4E APPROXIMATELY 581 NM EAST NORTHEAST 
OF LEGAZPI, PHILIPPINES. ANIMATED ENHANCED MULTISPECTRAL SATELLITE 
IMAGERY (MSI) DEPICTS A WELL-DEFINED, EXPOSED LOW LEVEL CIRCULATION 
CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION TO THE SOUTH OF THE 
CENTER. A 180113Z METOP-C ASCAT IMAGE REVEALS 20-25 KNOT WINDS WRAPPING 
INTO THE CIRCULATION FROM THE SOUTHERN PERIPHERY. ENVIRONMENTAL ANALYSIS 
FOR THE AREA INDICATES FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW 
VERTICAL WIND SHEAR (10-15 KTS), WARM SEA SURFACE TEMPERATURES (29-30 C) 
AND GOOD EQUATORWARD OUTFLOW ALOFT. MODEL GUIDANCE IS IN GOOD AGREEMENT 
THAT 90W WILL CONTINUE IN A WEST-NORTHWESTWARD TRACK WITH GFS SHOWING 
THE STRONGEST DEVELOPMENT IN THE NEXT 48 HOURS. MAXIMUM SUSTAINED 
SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS. MINIMUM SEA LEVEL 
PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE POTENTIAL FOR THE  
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS 
IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 
190600Z.
4. SEE REF A FOR DETAILS ON A TROPICAL CYCLONE FORMATION ALERT
LOCATED NEAR 23.5N 164.3E.//
NNNN