WTPN21 PGTW 220800

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//

SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 97W)//

RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN

140 NM EITHER SIDE OF A LINE FROM 11.1N 135.8E TO 14.5N 138.4E

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

IMAGERY AT 220600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED

NEAR 11.4N 135.9E. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 09

KNOTS.

2. REMARKS: THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR

10.2N 136.6E IS NOW LOCATED NEAR 11.2N 135.9E, APPROXIMATELY 170 NM

NORTHWEST OF YAP. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS

A LOW-LEVEL CIRCULATION (LLC) ALONG A TROUGH WITH FLARING CONVECTION

OVER SOUTHWESTERN PERIPHERY OF THE CIRCULATION. ENVIRONMENTAL ANALYSIS

REVEALS FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW TO MODERATE

VERTICAL WIND SHEAR (15 TO 20KTS), WARM SEA SURFACE TEMPERATURES (29 TO

30 C), AND GOOD EQUATORWARD UPPER-LEVEL OUTFLOW. GLOBAL DETERMINISTIC

MODELS BRIEFLY DEVELOP 97W, BUT IT QUICKLY GETS PULLED INTO THE FLOW OF

TYPHOON 17W. ENSEMBLE MODELS ALSO SHOW THE QUICK DEVELOPMENT OF 97W AND

A GENERAL NORTHERN TRACK OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED

SURFACE WINDS ARE ESTIMATED AT 17 TO 22 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

230800Z.//

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