WTPN21 PGTW 040630
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 97W)//

RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 19.3N 138.0E TO 26.7N 135.2E
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 040000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 19.2N 138.3E. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 09
KNOTS.

2. REMARKS: THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR
17.6N 138.9E IS NOW LOCATED NEAR 19.2N 138.3E, APPROXIMATELY 370 NM SOUTH-SOUTHWEST OF IWO TO, JAPAN. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS A DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC)
PARTIALLY OBSCURED BY MID- AND HIGH-LEVEL CLOUDS. DEEP CONVECTION HAS PERSISTED IN THE NORTHERN AND SOUTH-SOUTHWESTERN PERIPHERIES, WITH
WEAKER BURSTS NEAR THE CENTER, REFLECTING AN IMPROVED CONVECTIVE
SIGNATURE OVER THE PAST 12 HOURS. DRIER AIR IS WEDGED ALONG THE
NORTHWESTERN PERIPHERY, LIMITING CONVECTION IN THAT AREA. A 040007Z
METOP-C ASCAT PASS REVEALED A COMPACT CIRCULATION WITH ELEVATED WINDS
NEAR THE CORE, INDICATING THAT THE SYSTEM IS ON THE VERGE OF BECOMING
A TROPICAL DEPRESSION. OVERALL ENVIRONMENTAL CONDITIONS ARE ASSESSED
AS MARGINALLY FAVORABLE WITH LOW TO MODERATE (15-20 KTS) VERTICAL WIND
SHEAR, WARM (28-29 C) SEA SURFACE TEMPERATURES, GOOD EQUATORWARD
UPPER-LEVEL OUTFLOW, AND A ROBUST AMOUNT OF MOISTURE IN THE AREA.
GLOBAL MODELS ARE RELATIVELY CONSERVATIVE WITH DEVELOPMENT ON 97W,
WITH THE GFS AND ECMWF DETERMINISTIC MODELS DEPICTING LIMITED
ADDITIONAL DEVELOPMENT DURING THE NEXT 12 HOURS, BEFORE BROADENING OUT
THE LLCC THEREAFTER. MULTIPLE ENSEMBLE SYSTEMS AND THESE DYNAMICAL
MODELS AGREE ON 97W LARGELY HAVING A BROAD WIND FIELD WHILE
ACCELERATING NORTHWESTWARD. 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
050630Z.//
NNNN


--- ScorpioWeb v0.38a (Linux/x86_64)
* Origin: capitolcityonline.net * KY, USA (1:2320/107)