97W TCFA - 颱風討論

WTPN21 PGTW 191000
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/

1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
095 NM EITHER SIDE OF A LINE FROM 13.6N 141.8E TO 17.3N 142.6E
WITHIN THE NEXT 06 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 22 KNOTS. METSAT IMAGERY AT
190832Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 14.3N
142.0E. THE SYSTEM IS MOVING NORTH-NORTHEASTWARD AT 04 KNOTS.

2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.3N
141.8E, IS NOW LOCATED NEAR 14.3N 142.0E, APPROXIMATELY 170 NM WEST-
NORTHWEST OF GUAM. RECENT ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS INCREASINGLY TIGHTER CONVECTIVE BANDING FEATURES
WRAPPING TOWARDS THE DEVELOPING LOW LEVEL CIRCULATION CENTER (LLCC).
THE DEEPEST CONVECTION REMAINS FRAGMENTED ALONG THE WESTERN HALF OF
THE REGION. A RECENT 190516Z AMSU-B AND 190545Z SSMI MICROWAVE
IMAGERY PASS CONFIRMS THE LLCC RECENT DEVELOPMENTAL IMPROVEMENTS AND
WAS USED IN RELOCATING THE 190600Z POSITION FURTHER TO THE EAST.
UPPER LEVEL ANALYSIS INDICATES THE LLCC IS IN A REGION OF LOW
VERTICAL WIND SHEAR (VWS) (10 TO 15 KNOTS) AND GOOD DIVERGENCE. SEA
SURFACE TEMPERATURES (SSTS) ARE FAVORABLE FOR TROPICAL CYCLONE
DEVELOPMENT RANGING FROM 27-29 DEGREES CELSIUS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. DUE TO THE CONTINUED
IMPROVEMENT OF THE CONVECTIVE BANDING, GOOD UPPER LEVEL SUPPORT, AND
FAVORABLE SSTS, 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
201000Z.//

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