WTPN21 PGTW 291700

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

SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)//

RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN

120 NM EITHER SIDE OF A LINE FROM 15.9N 153.1E TO 16.0N 147.9E

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 291600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED

NEAR 15.9N 152.8E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 14

KNOTS.

2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 15.4N 155.0E

IS NOW LOCATED NEAR 15.9N 152.8E, APPROXIMATELY 494 NM EAST-NORTHEAST OF

GUAM. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A

MOSTLY OBSCURED LOW LEVEL CIRCULATION CENTER WITH DEEP FLARING

CONVECTION ALONG THE WESTERN PERIPHERY. ENVIRONMENTAL ANALYSIS REVEALS A

FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH STRONG POLEWARD UPPER-LEVEL

OUTFLOW, LOW VERTICAL WIND SHEAR (10-15 KTS), AND WARM SEA SURFACE

TEMPERATURES (29-30 C). GLOBAL DETERMINISTIC MODELS GENERALLY AGREE ON

93W CONTINUING TO CONSOLIDATE AS IT TRACKS WESTWARD. OUT OF THE ENSEMBLE

MODELS, ECENS IS THE MOST AGGRESSIVE REGARDING NEAR-TERM DEVELOPMENT.

MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS.

MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 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

301700Z.//

NNNN



WTPN21 PGTW 291700

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

SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)//

RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN

120 NM EITHER SIDE OF A LINE FROM 15.9N 153.1E TO 16.0N 147.9E

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 291600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED

NEAR 15.9N 152.8E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 14

KNOTS.

2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED NEAR

15.4N 155.0E IS NOW LOCATED NEAR 15.9N 152.8E, APPROXIMATELY 494 NM

EAST-NORTHEAST OF GUAM. ANIMATED ENHANCED INFRARED (EIR) SATELLITE

IMAGERY DEPICTS A MOSTLY OBSCURED LOW LEVEL CIRCULATION CENTER WITH DEEP

FLARING CONVECTION ALONG THE WESTERN PERIPHERY. ENVIRONMENTAL ANALYSIS

REVEALS A FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH STRONG POLEWARD

UPPER-LEVEL OUTFLOW, LOW VERTICAL WIND SHEAR (10-15 KTS), AND WARM SEA

SURFACE TEMPERATURES (29-30 C). GLOBAL DETERMINISTIC MODELS GENERALLY

AGREE ON 93W CONTINUING TO CONSOLIDATE AS IT TRACKS WESTWARD. OUT OF THE

ENSEMBLE MODELS, ECENS IS THE MOST AGGRESSIVE REGARDING NEAR-TERM

DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23

KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 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

301700Z.//

NNNN