WTPS21 PGTW 210600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 96P)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 18.9S 148.5E TO 20.5S 156.0E 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 30 TO 35 KNOTS. METSAT IMAGERY AT 210530Z INDICATES 
THAT A CIRCULATION CENTER IS LOCATED NEAR 19.0S 149.4E. THE SYSTEM IS 
MOVING EASTWARD AT 09 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 96P) PREVIOUSLY LOCATED 
NEAR 18.6S 147.5E IS NOW LOCATED NEAR 19.0S 149.4E, APPROXIMATELY 247 
NM EAST-SOUTHEAST OF CAIRNS, AUSTRALIA. ANIMATED MULTISPECTRAL 
SATELLITE IMAGERY DEPICTS A BROAD LOW-LEVEL CIRCULATION CENTER (LLCC), 
WITH DEEP CONVECTION SHEARED OVER THE EASTERN QUADRANT. A 202348Z 
ASCAT-C IMAGE REVEALS PRIMARILY 15-25 KNOT WINDS AROUND THE PERIPHERY 
OF THE ELONGATED CIRCULATION, WITH A LIMITED REGION OF 30-35 KNOT 
WINDS OVER THE EASTERN QUADRANT ASSOCIATED WITH THE PERSISTENT DEEP 
CONVECTION. ANIMATED RADAR IMAGERY FROM THE TOWNSVILLE RADAR SHOWS 
FAIRLY DISORGANIZED DEEP CONVECTION ALONG THE PERIPHERY OF THE LLCC. 
SURFACE OBSERVATIONS FROM CREAL REEF INDICATE 25-30 KNOT SUSTAINED 
EASTERLY (10-MINUTE AVERAGE) WINDS, WHICH IS CONSISTENT WITH RECENT 
ASCAT DATA. SOUTHEASTERLY WINDS ALONG THE EASTERN COAST OF AUSTRALIA 
ARE SIGNIFICANTLY LOWER, RANGING FROM 15 TO 25 KNOTS. INVEST 96P IS 
LOCATED UNDER MODERATE SUBTROPICAL WESTERLIES, WITH LOW TO MODERATE 
(15-20 KNOTS) VERTICAL WIND SHEAR. GLOBAL MODELS INDICATE A QUICK 
EASTWARD TO EAST-SOUTHEASTWARD TRACK AND A SHORT WINDOW FOR WARM-CORE 
DEVELOPMENT BEFORE THE SYSTEM TRANSITIONS INTO A SUBTROPICAL STORM.    
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 30 TO 35 KNOTS. 
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 998 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 
220600Z.//
NNNN