WTPS31 PGTW 110300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 18P (HAMISH) WARNING NR 012//
RMKS/
1. TROPICAL CYCLONE 18P (HAMISH) WARNING NR 012
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
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WARNING POSITION:
110000Z --- NEAR 24.2S 155.2E
MOVEMENT PAST SIX HOURS - 285 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 085 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
REPEAT POSIT: 24.2S 155.2E
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FORECASTS:
12 HRS, VALID AT:
111200Z --- 23.6S 154.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 325 DEG/ 04 KTS
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24 HRS, VALID AT:
120000Z --- 22.9S 154.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 325 DEG/ 04 KTS
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36 HRS, VALID AT:
121200Z --- 22.2S 153.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 48 HR POSIT: 320 DEG/ 04 KTS
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EXTENDED OUTLOOK:
48 HRS, VALID AT:
130000Z --- 21.5S 153.0E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
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REMARKS:
110300Z POSITION NEAR 24.0S 155.1E.
TROPICAL CYCLONE (TC) 18P (HAMISH), LOCATED APPROXIMATELY 230 NM
NORTHEAST OF BRISBANE, AUSTRALIA, HAS TRACKED WESTWARD AT 04 KNOTS
OVER THE PAST 06 HOURS. ANIMATED MULTISPECTRAL SATELLITE AND RECENT
MICROWAVE IMAGERY SHOW A FULLY EXPOSED LOW LEVEL CIRCULATION CENTER
TRACKING WESTWARD AWAY FROM THE DEEP CONVECTION WHICH IS SHEARED TO
THE EAST. THE CURRENT POSITION AND MOTION ARE BASED UPON THE
ANIMATED IMAGERY AS WELL AS A 102022Z QSCAT IMAGE. THE CURRENT
INTENSITY IS BASED ON DVORAK ESTIMATES RANGING FROM 35 TO 55 KNOTS
AND THE PREVIOUSLY MENTIONED QSCAT IMAGE. AFTER REVERSING DIRECTION
NEAR 10/12Z THE SYSTEM HAS TRACKED SLOWLY WESTWARD OVER THE PAST 12
HOURS, AND IS FORECAST TO TRACK INCREASINGLY NORTHWESTWARD UNDER THE
STEERING INFLUENCE OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE WHICH IS
BUILDING WEST AND SOUTH OF THE SYSTEM. THIS DEVELOPMENT IS EVIDENT
ON THE 10/12Z 700 MB ANALYSIS. TC 18P WILL MAINTAIN SLOW FORWARD
TRACK SPEED AS IT BATTLES COMPETING STEERING FLOW BETWEEN THE
PRIMARY INFLUENCE TO THE WEST AND SOUTH AND NORTHWESTERLY FLOW
ORIGINATING FROM A WEAKER RIDGE BUILDING TO THE NORTHEAST. TC 18P
WILL WEAKEN STEADILY OVER THE FORECAST PERIOD AND ULTIMATELY
DISSIPATE AS A SIGNIFICANT TROPICAL CYCLONE NEAR TAU 48 WHILE MOVING
NORTHWESTWARD ALONG THE AUSTRALIAN COAST. THIS FORECAST IS BASED
UPON THE MAJORITY OF DYNAMIC AIDS (WITH THE EXCEPTION OF NGPS AND
WBAR) WHICH DEPICT THE NORTHWESTERLY MOTION AND CONTINUED WEAKENING
TREND. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 110000Z IS 20 FEET. NEXT
WARNINGS AT 111500Z AND 120300Z.
