WTPN21 PHNC 191230
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 96E) REISSUED//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/181221ZSEP25//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
135 NM EITHER SIDE OF A LINE FROM 16.0N 108.9W TO 19.8N 113.8W
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 28 TO 33 KNOTS. METSAT
IMAGERY AT 191200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 18.4N 112.1W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 96E) PREVIOUSLY LOCATED 
NEAR 16.2N 109.1W IS NOW LOCATED NEAR 18.4N 112.1W, APPROXIMATELY 130 NM 
EAST OF CLARION ISLAND. ANIMATED ENHANCED INFRARED (EIR) SATELLITE 
IMAGERY DEPICTS FLARING CONVECTION DISPLACED FAR TO THE WEST OF AN 
EXPOSED LOW LEVEL CIRCULATION CENTER. A 190515 METOP-C ASCAT REVEALS A 
DISORGANIZED CIRCULATION THAT IS BROADLY STRETCHED HORIZONTALLY FROM 
EAST TO WEST WITH ELEVATED (20-25 KTS) WINDS WITHIN THE WESTERN 
PERIPHERY OF THE SYSTEM. ENVIRONMENTAL ANALYSIS REVEALS MARGINALLY 
FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW TO MODERATE NORTHEASTERLY 
VERTICAL WIND SHEAR (15-20 KTS), MODERATE POLEWARD OUTFLOW ALOFT, DRY 
AIR ENTRAINMENT, AND WARM SEA SURFACE (29-30 C) TEMPERATURES. GLOBAL 
DETERMINISTIC MODELS ARE IN GOOD AGREEMENT ON A NORTHWESTWARD TRACK WITH 
LITTLE DEVELOPMENT IN THE SHORT TERM. GLOBAL ENSEMBLE MODELS ARE IN 
AGREEMENT ON THE TRACK OF THE SYSTEM, HOWEVER, THEY ARE IN DISAGREEMENT 
ON THE INTENSITY OF THE SYSTEM WITH ECENS BEING MORE AGGRESSIVE THAN 
GEFS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 28 TO 33 KNOTS. 
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE 
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN 
THE NEXT 24 HOURS IS HIGH. THIS SUPERSEDES REF A (WTPN21 PHNC 181230). 
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 
201230Z.
//
NNNN