(1) AN AREA OF CONVECTION (INVEST 98B) HAS PERSISTED NEAR 4.5N
92.8E, APPROXIMATELY 912 NM EAST-SOUTHEAST OF CHENNAI, INDIA.
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS AN AREA
OF DISORGANIZED, FLARING CONVECTION OBSCURING A BROAD AREA OF LOW
LEVEL TURNING. THE POSITION OF THE SYSTEM CENTER IS PLACED WITH POOR
CONFIDENCE BUT IS CONSTRAINED SOMEWHAT BY A 281017Z SSMIS 91GHZ
IMAGE. THE ENVIRONMENT IS MARGINALLY FAVORABLE FOR CONSOLIDATION
WITH ROBUST EQUATORWARD AND WESTWARD OUTFLOW ALOFT AND WARM (28-29
CELSIUS) SEA SURFACE TEMPERATURES BELOW OFFSET SLIGHTLY BY MODERATE
(10-15 KTS) VERTICAL WIND SHEAR ALONG THE SOUTHERN AND SOUTHWESTERN
QUADRANTS. NUMERICAL MODEL SOLUTIONS ARE IN FAIR AGREEMENT THAT
INVEST 98B WILL CONTINUE TO CONSOLIDATE AS IT DRIFTS WESTWARD
TOWARDS SRI LANKA OVER THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 17 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 LOW.
(1) THE AREA OF CONVECTION (INVEST 98B) PREVIOUSLY LOCATED
NEAR 4.5N 92.8E IS NOW LOCATED NEAR 7.5N 88.2E, APPROXIMATELY 493 NM
EAST OF COLOMBO, SRI LANKA. ANIMATED ENHANCED INFRARED (EIR)
SATELLITE IMAGERY DEPICTS AN AREA OF DEEPENING AND CONSOLIDATING
CENTRAL CONVECTION THAT IS OBSCURING A BROAD LOW LEVEL CIRCULATION.
FORMATIVE BANDING, ALBEIT FRAGMENTED, CAN ALSO BE SEEN CLOSING IN
FROM THE NORTHERN PERIPHERIES. ANALYSIS INDICATES THE ENVIRONMENT IS
FAVORABLE FOR DEVELOPMENT WITH ROBUST EQUATORWARD AND WESTWARD
OUTFLOW ALOFT, WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES, AND LOW
(<15 KTS) VERTICAL WIND SHEAR. NUMERICAL MODEL SOLUTIONS ARE IN GOOD
AGREEMENT THAT INVEST 98B WILL CONTINUE TO CONSOLIDATE AND INTENSIFY
AS IT TRACKS WEST-NORTHWESTWARD TOWARD SRI LANKA. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 17 TO 23 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.
WTIO21 PGTW 300930
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
080 NM EITHER SIDE OF A LINE FROM 6.5N 87.5E TO 6.3N 85.1E 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 25 TO 30 KNOTS. METSAT IMAGERY AT
300830Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 6.5N
87.3E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 10 KNOTS.
2. REMARKS:
ANIMATED ENHANCED MULTISPECTRAL IMAGERY (EMI) DISPLAYS AN AREA OF
FLARING CONVECTION THAT IS OBSCURING A BROAD LOW LEVEL CIRCULATION.
A PARTIAL 300711Z AMSR2 89GHZ PASS SHOWS FORMATIVE BANDING WITH DEEP
CONVECTION IN THE NORTHEAST PERIPHERY. ENVIRONMENTAL ANALYSIS
INDICATES FAVORABLE CONDITIONS FOR TROPICAL DEVELOPMENT WITH ROBUST
POLEWARD AND WESTWARD OUTFLOW ALOFT, LOW (5-10 KTS) VERTICAL WIND
SHEAR (VWS), AND WARM (28-29 CELSIUS) SEA SURFACE TEMPERATURES.
NUMERICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT THAT INVEST 98B WILL
CONTINUE TO CONSOLIDATE AND INTENSIFY AS IT TRACKS WEST-
NORTHWESTWARD TOWARD SRI LANKA. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1000 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
010930Z.
//
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