WTPN21 PGTW 040530
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 1.4N 175.0E TO 6.0N 170.8E
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 18 TO 23 KNOTS. METSAT
IMAGERY AT 040500Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 2.5N 174.4E. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 21
KNOTS.
2. REMARKS:
THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED NEAR 2.7N
177.8E, IS NOW LOCATED NEAR 2.5N 174.4E, APPROXIMATELY 545 NM
SOUTHEAST OF KWAJALEIN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS TIGHT TROUGHING AND SCATTERED CONVECTION. A 040409Z
SSMIS 91GHZ IMAGE REVEALS POORLY ORGANIZED TURNING WITH DEEP
CONVECTION DISPLACED TO THE NORTH. A 032209Z METOP-B ASCAT PASS
INDICATES 20 KNOT WINDS AROUND THE TROUGH AXIS. UPPER LEVEL ANALYSIS
DEPICTS LOW (10-15 KNOTS) VERTICAL WIND SHEAR AND FAVORABLE
DIVERGENCE WITH DUAL OUTFLOW CHANNELS. SEA SURFACE TEMPERATURES (30-
32 CELSIUS) IN THE SURROUNDING WATERS ARE CONDUCIVE FOR FUTURE
DEVELOPMENT. GLOBAL MODELS SHOW LITTLE DEVELOPMENT OVER THE NEXT 48-
72 HOURS, EXCEPT FOR GFS WHICH SHOWS DEVELOPMENT IN THE NEXT 24
HOURS WITH THE SYSTEM MAINTAINING A NORTHWEST TRACK. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 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
050530Z.//
NNNN
(1) THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED
NEAR 3.0N 175.0E, IS NOW LOCATED NEAR 2.7N 177.8E, APPROXIMATELY 600
NM SOUTHEAST OF KWAJALEIN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS A PARTIALLY-EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC)
SURROUNDED BY WEAK, SCATTERED CONVECTION. A 030422Z SSMIS 91GHZ
IMAGE ALSO SHOWS A POORLY-ORGANIZED LLCC. UPPER LEVEL ANALYSIS
DEPICTS LOW (10-15 KNOT) VERTICAL WIND SHEAR AND FAVORABLE POLEWARD
OUTFLOW. SEA SURFACE TEMPERATURES (28-30 CELSIUS) IN THE SURROUNDING
WATERS ARE CONDUCIVE FOR FUTURE DEVELOPMENT. GLOBAL MODELS SHOW
WEAK, SLOW DEVELOPMENT OVER THE NEXT 48-72 HOURS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1010 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.
(1) AN AREA OF CONVECTION (INVEST 90W) HAS PERSISTED NEAR 3.0N
175.0E, APPROXIMATELY 287 NM SOUTHEAST OF KWAJALEIN. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY AND A 021535Z SSMI 85GHZ PARTIAL
IMAGE SHOW A POORLY-ORGANIZED LOW LEVEL CIRCULATION CENTER (LLCC)
WITH SCATTERED CONVECTION. UPPER LEVEL ANALYSIS DEPICTS LIGHT (05-15
KNOT) VERTICAL WIND SHEAR AND FAVORABLE POLEWARD OUTFLOW. A RECENT
ASCAT PASS REVEALS A BROAD AND ASYMMETRIC CIRCULATION CENTER. SEA
SURFACE TEMPERATURES (28-30 CELSIUS) IN THE SURROUNDING WATERS ARE
CONDUCIVE FOR FUTURE DEVELOPMENT. GLOBAL MODELS SHOW WEAK, SLOW
DEVELOPMENT OVER THE NEXT 48-72 HOURS. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1010 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.
