WTPN21 PHNC 161900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 97E) REISSUED//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/151851ZJUL2021//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT (WTPN21 PHNC 
151900)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
155 NM EITHER SIDE OF A LINE FROM 13.3N 103.5W TO 16.7N 110.9W
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 161730Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 13.8N 103.9W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 12
KNOTS.
2. REMARKS: AN AREA OF CONVECTION (INVEST 97E) PREVIOUSLY LOCATED 
NEAR 10N 99W IS NOW LOCATED NEAR 13.8N 103.9W, APPROXIMATELY 315 NM 
SOUTH OF MANZANILLO, MEXICO. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY DEPICTS A BROAD LOW LEVEL CIRCULATION (LLC) WITH FLARING 
DEEP CONVECTION OVER THE EASTERN SEMICIRCLE. A 161144Z SSMIS 91 GHZ 
MICROWAVE IMAGE SHOWS FORMATIVE BANDING BEGINNING TO WRAP INTO THE 
LLC WITH DISORGANIZED CONVECTION TO THE NORTH AND EAST OF THE SYSTEM 
CENTER. ENVIRONMENTAL ANALYSIS REVEALS THAT INVEST 97E IS LOCATED 
WITHIN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH MODERATE (15-20 
KTS) VERTICAL WIND SHEAR, GOOD EQUATORWARD OUTFLOW, AND WARM (29-30 
DEGREES CELSIUS) SEA SURFACE TEMPERATURES. GLOBAL NUMERICAL MODELS 
INDICATE THAT INVEST 97E WILL INTENSIFY AND CONSOLIDATE FURTHER AS 
IT TRACKS WEST-NORTHWESTWARD OVER THE NEXT 24-48 HOURS. MAXIMUM 
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA 
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. THE POTENTIAL FOR 
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 
HOURS REMAINS HIGH. THIS SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 
171900Z.//
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