WTPN21 PGTW 191430
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 92W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
150 NM EITHER SIDE OF A LINE FROM 20.9N 130.7E TO 20.1N 123.4E
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 191200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 20.9N 130.7E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 04
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 92W) PREVIOUSLY LOCATED 
NEAR 21.0N 130.8E IS NOW LOCATED NEAR 20.9N 130.7E, APPROXIMATELY 535 
NM EAST-NORTHEAST OF APARRI, PHILIPPINES. ANIMATED ENHANCED INFRARED 
SATELLITE IMAGERY SHOWS PERSISTENT CONVECTION OBSCURING A PARTIALLY 
EXPOSED LOW LEVEL CIRCULATION (LLC). A 190932Z SSMIS 91GHZ COLOR 
COMPOSITE MICROWAVE IMAGE DEPICTS A PARTIALLY EXPOSED LLC WITH 
FORMATIVE DEEP CONVECTIVE BANDING OVER THE SOUTHERN SEMICIRCLE. A 
191205Z ASCAT-B PASS REVEALS A WELL-DEFINED CIRCULATION WITH 20 KT 
WINDS TO THE EAST AND 20-25KT WINDS OVER THE WESTERN SEMICIRCLE 
ASSOCIATED WITH AN ADJACENT NORTHEAST COLD SURGE. ADDITIONALLY, A 
191000Z SHIP REPORT 150 NM TO THE WEST-NORTHWEST REPORTS 24 KT WINDS. 
ENVIRONMENTAL ANALYSIS DEPICTS FAVORABLE CONDITIONS FOR 
INTENSIFICATION AS SHOWN BY 10-15KT VWS, ROBUST UPPER LEVEL 
DIVERGENCE WITH STRONG EQUATORWARD OUTFLOW, AND WARM (28-29C) SEA 
SURFACE TEMPERATURES. GLOBAL MODELS ARE IN GENERAL AGREEMENT WITH A 
WESTWARD TRACK OVER THE NEXT TWO DAYS WITH STEADY DEVELOPMENT. 
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 
201430Z.//
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