WTPN21 PGTW 012030
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
REF/A/NAVMARFCSTCEN PEARL HARBOR HI/301851Z JUN 08//
AMPN/REF IS TROPICAL CYCLONE FORMATION ALERT (WTPN21 PGTW 302000)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
180 NM EITHER SIDE OF A LINE FROM 14.9N 105.8W TO 19.2N 111.1W
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 IM-
AGERY AT 012000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.4N 106.4W.  THE SYSTEM IS MOVING NORTHWESTWARD AT 08
KNOTS.
2. REMARKS: RECENT ANIMATED METSAT IMAGERY CONTINUES TO INDICATE
A CONSOLIDATING AREA OF CYCLONIC TURNING, WITH WEAK CONVECTIVE
BANDING. A 011618Z ASCAT PASS SHOWS WINDS OF 15 KNOTS NEAR THE
CENTER, WITH WINDS OF 20 TO 25 KT ON THE OUTER EDGES. THE SYSTEM
REMAINS IN A GENERALLY FAVORABLE ENVIRONMENT FOR DEVELOPMENT, WITH
A 200 MB ANTICYCLONE TO EAST PROVIDING GOOD DIFFLUENCE ALOFT AND
LOW VERTICAL WIND SHEAR. THESE FACTORS MAKE FURTHER CONSOLIDATION OF
THE LOW LEVEL CENTER LIKELY. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 18 TO 23 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1008 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFI-
CANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS GOOD. THIS
SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
022030Z.
//