WTPN21 PGTW 150130

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

SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 90W)//

RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN

160 NM EITHER SIDE OF A LINE FROM 14.8N 151.0E TO 22.1N 149.8E

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 150100Z INDICATES THAT A CIRCULATION CENTER IS LOCATED

NEAR 15.1N 150.9E. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 13

KNOTS.

2. REMARKS: THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED

NEAR 13.0N 152.7E IS NOW LOCATED NEAR 15.1N 150.9E, APPROXIMATELY

374 NM EAST-NORTHEAST OF ANDERSEN AFB, GUAM. ANIMATED MULTISPECTRAL

SATELLITE IMAGERY (MSI) DEPICTS A BROAD, PARTIALLY EXPOSED LOW-LEVEL

CIRCULATION (LLC) WITH PERSISTENT CONVECTION BUILDING OVER THE CENTER.

ENVIRONMENTAL ANALYSIS REVEALS FAVORABLE CONDITIONS FOR DEVELOPMENT WITH

LOW VERTICAL WIND SHEAR (5 TO 15KTS), DUAL-CHANNEL UPPER-LEVEL OUTFLOW,

AND WARM SEA SURFACE TEMPERATURES (29 TO 30 C). GLOBAL DETERMINISTIC AND

ENSEMBLE MODELS ARE IN GOOD AGREEMENT ON 90W FURTHER CONSOLIDATING WITH

A NORTH-NORTHWESTWARD TRACK OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED

SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL

PRESSURE IS ESTIMATED TO BE NEAR 1002 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

160130Z.//

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