WTIO21 PGTW 061800
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT CANCELLATION //
REF/A/MSG/NAVPACMETOCCEN PEARL HARBOR HI/051921Z JUN 08//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT (WTIO21
PGTW 051930)//
RMKS/
1. REMARKS:
THIS CANCELS REF A. THE AREA OF CONVECTION PREVIOUSLY LOCATED
NEAR 19.1N 63.7E, IS NOW LOCATED NEAR 19.6N 60.9E, APPROXIMATELY
270 NM SOUTH=SOUTHEAST OF MUSCAT, OMAN. RECENT ANIMATED INFRARED
AND MULTISPECTRAL SATELLITE IMAGERY SHOWS FLARING DEEP CONVECTION
SHEARED TO THE WEST OF A LOW LEVEL CIRCULATION CENTER (LLCC) EVI-
DENT IN A 061432Z SSMI MICROWAVE SATELLITE PASS. THE DISTURBANCE
LIES IN A REGION OF MODERATE EASTERLY VERTICAL WIND SHEAR ON THE
EQUATORWARD SIDE OF AN UPPER LEVEL RIDGE AXIS. VERTICAL SHEAR HAS
INCREASED OVER THE PAST 24 HOURS. WESTWARD DIFFLUENCE ALOFT,
ALTHOUGH WEAKENED FROM 24 HOURS AGO, CONTINUES TO FUEL SOME CON-
VECTIVE DEVELOPMENT, PARTICULARLY TO THE WEST OF THE LLCC. THE
CONVECTION IS NO LONGER SUFFICIENT TO SUSTAIN THE LOW LEVEL
CIRCULATION IN THE PRESENCE OF SUSTAINED SHEAR. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 999 MB.  DUE TO DECREASED LOW
LEVEL ORGANIZATION, AND MODERATE VERTICAL WIND SHEAR, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS DOWNGRADED TO POOR.//