WTPN21 PGTW 101330
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 94W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
180 NM EITHER SIDE OF A LINE FROM 9.9N 144.0E TO 14.0N 133.7E
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 20 TO 25 KNOTS. METSAT
IMAGERY AT 101300Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 10.3N 143.1E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 17
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 94W) PREVIOUSLY LOCATED 
NEAR 8.6N 145.7E IS NOW LOCATED NEAR 10.3N 143.1E, APPROXIMATELY 211 
NM SOUTH-SOUTHWEST OF GUAM. ANIMATED ENHANCED INFRARED IMAGERY (EIR) 
DEPICTS AN IMPROVING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH 
INCREASING CURVED CONVECTIVE BANDING BUILDING AROUND THE PERIPHERY. 
ADDITIONALLY, CONVECTION IS BUILDING OVER THE CENTER OF THE SYSTEM, 
CONSISTENT WITH AN INTENSIFYING TROPICAL SYSTEM. ENVIRONMENTAL 
ANALYSIS REVEALS A FAVORABLE ENVIRONMENT FOR FURTHER DEVELOPMENT WITH 
LOW VERTICAL WIND SHEAR (VWS) OF 10-15 KTS, WEAK UPPER-LEVEL OUTFLOW, 
AND WARM SEA SURFACE TEMPERATURES OF 29-30C. GLOBAL DETERMINISTIC 
MODELS ARE IN GOOD AGREEMENT THAT INVEST 94W WILL CONTINUE TO 
CONSOLIDATE AS IT TRACKS WEST-NORTHWESTWARD OVER THE NEXT 24 HRS. WITH 
GFS BEING THE MOST AGGRESSIVE MODEL, GFS AND ECMWF BOTH INDICATE 25 
KTS IN THE SYSTEMS WIND FIELD WITHIN THE NORTHERN SEMICIRCLE. AS FOR 
NAVGEM, THE MODEL IS FORECASTING A SURFACE CIRCULATION SLIGHTLY LESS, 
WITH WINDS OF 15-20 KTS THROUGH THE REST OF THE FORECAST PERIOD WHILE 
THE SURFACE CIRCULATION REMAINS BROAD. MAXIMUM SUSTAINED SURFACE WINDS 
ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS 
ESTIMATED TO BE NEAR 1004 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 
111330Z.//
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