WDPN31 PGTW 070300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 02W (NEPARTAK)
WARNING NR 17//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   SUPER TYPHOON 02W (NEPARTAK), LOCATED APPROXIMATELY 275 NM
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 14
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A TIGHTLY WOUND CYCLONE WITH A WELL DEFINED EYE
FEATURE GIVING HIGH CONFIDENCE TO THE INITIAL POSITION. CONVECTIVE
BANDING HAS REFORMED OVER THE LAST SIX HOURS ON THE NORTH AND SOUTH
PERIPHERIES AS OBSERVED IN LOCAL RADAR IMAGERY AND A 062234Z SSMIS
91 GHZ IMAGE. THE CURRENT INTENSITY IS ASSESSED AT 150 KNOTS AND
IS BASED ON CURRENT INTENSITY DVORAK ESTIMATES FROM ALL REPORTING
AGENCIES. STY 02W HAS MAINTAINED INTENSITY OVER THE LAST SIX HOURS,
PARTLY DUE TO THE RECENT DEVELOPMENT OF DEEP CONVECTIVE BANDS
FEEDING INTO THE SYSTEM AS WELL AS GOOD DIFLUENCE ALOFT AND VERY
WARM SEA SURFACE TEMPERATURES.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. STY 02W WILL CONTINUE TRACKING GENERALLY WEST-NORTHWESTWARD
ALONG THE PERIPHERY OF THE SUBTROPICAL RIDGE TO THE NORTHEAST UNTIL
IT MAKES LANDFALL OVER CENTRAL TAIWAN IN THE NEXT 12 TO 24 HOURS.
STY 02W WILL WEAKEN CONSIDERABLY BEYOND TAU 24 DUE TO LAND
INTERACTION, THEN REORGANIZE OVER THE TAIWAN STRAIT BEFORE MAKING
LANDFALL AGAIN OVER CHINA SOMETIME BETWEEN TAU 36 AND 48.
   C. IN THE EXTENDED PERIOD, STY 02W WILL CONTINUE TRACKING OVER
LAND ROUNDING THE STEERING RIDGE AXIS, TURNING NORTH, UNTIL IT
DISSIPATES BY TAU 72. NUMERICAL MODELS DIFFER REGARDING THE SPEED
AND TIGHTNESS OF THE POLEWARD TURN ONCE OVERLAND, BUT SHOW TIGHT
GROUPING IN THE TRACK MAKING LANDFALL OVER TAIWAN AND CHINA LENDING
HIGH CONFIDENCE TO THE JTWC FORECAST TRACK.//