WTXS32 PGTW 070900
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
REF/A/MSG/NAVPACMETOCCEN/PEARL HARBOR HI/070152MAR2007//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. TROPICAL CYCLONE 18S (JACOB) WARNING NR 002
02 ACTIVE TROPICAL CYCLONES IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
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WARNING POSITION:
070600Z --- NEAR 12.5S 107.3E
MOVEMENT PAST SIX HOURS - 275 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 12.5S 107.3E
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FORECASTS:
12 HRS, VALID AT:
071800Z --- 12.2S 106.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 300 DEG/ 03 KTS
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24 HRS, VALID AT:
080600Z --- 11.9S 106.0E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 345 DEG/ 02 KTS
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36 HRS, VALID AT:
081800Z --- 11.5S 105.9E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 025 DEG/ 02 KTS
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EXTENDED OUTLOOK:
48 HRS, VALID AT:
090600Z --- 11.1S 106.1E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
---
REMARKS:
070900Z POSITION NEAR 12.4S 107.1E.
TROPICAL CYCLONE (TC) 18S (JACOB), LOCATED APPROXIMATELY 385 NM
SOUTH OF JAKARTA, INDONESIA, HAS TRACKED WESTWARD AT 08 KNOTS
OVER THE PAST SIX HOURS. TC 18S IS TRACKING ALONG THE WESTWARD
EXTENSION OF A SUBTROPICAL STEERING RIDGE ANCHORED OVER SOUTH-
WESTERN AUSTRALIA. THIS RIDGE EXTENSION IS EXPECTED TO WEAKEN
IN RESPONSE TO AN APPROACHING MIDLATITUDE TROUGH TO THE SOUTH-
WEST OF THE SYSTEM. AS THE STEERING RIDGE WEAKENS, STRONG LOW
TO MID-LEVEL WESTERLY FLOW TO THE NORTH OF THE SYSTEM WILL EXERT
A COMPETING STEERING INFLUENCE. THE SYSTEM WILL SLOW AND BEGIN
TO TURN TO THE NORTH AND THEN TO THE NORTHEAST AS THE MID-LEVEL
WESTERLY FLOW EXERTS MORE OF A STEERING INFLUENCE AND AS THE
SYSTEM INTERACTS WEAKLY WITH TC 17S. UPPER AIR ANALYSIS REVEALS
MODERATE VERTICAL WIND SHEAR AND THIS IS EXPECTED DECREASE ONLY
SLIGHTLY THROUGH THE FORECAST PERIOD. THE APPROACHING MIDLATITUDE
TROUGH WILL INCREASE POLEWARD OUTFLOW AND ALLOW TC 18S TO INTEN-
SIFY AT NEARLY A CLIMATALOGICAL RATE THROUGH TAU 36. AS THE
SYSTEM BECOMES QUASI-STATIONARY BETWEEN TAUS 36 AND 48, UPWELLING
WILL CAUSE A LESS THAN CLIMATOLOGICAL RATE OF INTENSIFICATION.
THE DYNAMIC AIDS ARE IN POOR AGREEMENT AND THE MODEL FIELDS ARE
HAVING DIFFICULTY RESOLVING THE LOW LEVEL ENVIRONMENT FOR THIS
SYSTEM. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 070600Z IS 15 FEET.
NEXT WARNINGS AT 072100Z AND 080900Z. REFER TO TROPICAL CYCLONE
17S (GEORGE) WARNINGS (WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.//