WTIO21 PGTW 050030
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
050 NM EITHER SIDE OF A LINE FROM 20.2N 87.8E TO 22.1N 87.3E
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 27 TO 32 KNOTS. METSAT IM-
AGERY AT 050000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 20.4N 87.8E.  THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 04
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 19.5N
87.8E IS NOW LOCATED NEAR 20.4N 87.8E, APPROXIMATELY 125 NM SOUTH-
SOUTHWEST OF KOLKATA, INDIA. RECENT ANIMATED INFRARED SATELLITE
IMAGERY SHOWS DEEP CONVECTION PERSISTING NEAR THE CENTER OF A LOW
LEVEL CIRCULATION CENTER (LLCC) EVIDENT IN RECENT MICROWAVE
SATELLITE IMAGERY. THIS DISTURBANCE IS MOVING INTO AN AREA OF
DECREASING VERTICAL WIND SHEAR AND FAVORABLE POLEWARD AND
EQUATORWARD OUTFLOW ASSOCIATED WITH RIDGING ALOFT. RECENT
OBSERVATIONS FROM REPORTING STATIONS ALONG THE NORTHEASTERN INDIAN
COAST, NEAR THE CENTER OF LOW PRESSURE, INDICATE SURFACE PRESSURES
RANGING FROM 994 TO 996 MB. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 27 TO 32 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 995 MB. BASED ON THE GOOD LOW LEVEL SIGNATURE, LOW
ESTIMATED CENTRAL SURFACE PRESSURE, AND IMPROVING UPPER LEVEL
SUPPORT, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS IS GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
060030Z.//