WTXS31 PGTW 030900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 01S (DAHLIA) WARNING NR 014//
RMKS/
1. TROPICAL CYCLONE 01S (DAHLIA) WARNING NR 014
01 ACTIVE TROPICAL CYCLONE IN SOUTH IO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
030600Z --- NEAR 13.8S 112.4E
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.8S 112.4E
---
FORECASTS:
12 HRS, VALID AT:
031800Z --- 15.8S 111.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 200 DEG/ 08 KTS
---
24 HRS, VALID AT:
040600Z --- 17.3S 111.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 200 DEG/ 03 KTS
---
36 HRS, VALID AT:
041800Z --- 17.9S 111.1E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
030900Z POSITION NEAR 14.3S 112.3E.
TROPICAL CYCLONE 01S (DAHLIA), LOCATED APPROXIMATELY 519 NM NORTH
OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWARD AT 13 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS
A PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH
PULSATING CONVECTION STRUGGLING TO ORGANIZE AND CONSOLIDATE. THERE
IS HIGH CONFIDENCE IN THE INITIAL POSITION BASED ON SATELLITE FIXES
AND THE EXPOSED LLCC IN SATELLITE IMAGERY. THE INITIAL INTENSITY IS
ASSESSED AT 35 KNOTS AND IS BASED ON THE HIGHLY SYMMETRIC LOW LEVEL
STRUCTURE AND A 030149Z SATCON ESTIMATE OF 38 KNOTS DESPITE, ALSO
NOTING AGENCY CURRENT INTENSITY ESTIMATES RANGING FROM T1.5 TO T2.5
(25 TO 35 KNOTS). UPPER-LEVEL ANALYSIS SHOWS STRONG EASTERLIES FROM
A NEARBY RIDGE TO SOUTHEAST CREATING A MODERATE WIND SHEAR
ENVIRONMENT. DIFFLUENCE SOUTHWEST OF THE SYSTEM ALSO APPEARS ROBUST
AND AN APPROACHING LONGWAVE TOUGH IS PROVIDING A WEAK POLEWARD
OUTFLOW CHANNEL. SSTS IN THE REGION ARE CURRENTLY FAVORABLE AROUND
28 CELSIUS, HOWEVER TEMPERATURES DECLINE RAPIDLY SOUTH OF 15
DEGREES. TC 01S IS CURRENTLY TRACKING SOUTHWARD ALONG THE WESTERN
BOUNDARY OF A MID-LEVEL SUBTROPICAL RIDGE TO THE EAST. TC 01S WILL
CONTINUE ALONG THE RIDGE BOUNDARY TRACKING SOUTHWEST TO SOUTH-
SOUTHWEST OVER THE NEXT 24 HOURS. THE LLCC IS FORECAST TO REMAIN IN
TACT WITH BOUTS OF FLARING CONVECTION OVER THE NEXT COUPLE DAYS.
HOWEVER, INCREASING WIND SHEAR AND COOLER WATER TEMPERATURES WILL
MITIGATE THE POSSIBILITY OF CONVECTIVE CONSOLIDATION AND THE SYSTEM
WILL PERSIST AS A WEAK TROPICAL CYCLONE. TC 01S IS FORECAST TO
DISSIPATE BY TAU 36. DYNAMIC MODEL GUIDANCE SHOWS CONSISTENCY OVER
THE NEXT 36 HOURS AS THE SYSTEM WEAKENS. BEYOND TAU 36 IT IS UNCLEAR
WHERE THE REMNANTS OF TC 01S WILL TRACK. AS A WEAK DEPRESSION, THE
MID-LEVEL RIDGE WILL HAVE LESS IMPACT ON STEERING AND MOST LIKELY
WILL TRACK BACK NORTH TO NORTHEAST IN THE LOW LEVEL FLOW, LEAVING
THE POSSIBILITY OF REGENERATION SEVERAL DAYS OUT. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 030600Z IS 12 FEET. NEXT WARNINGS AT
031500Z, 032100Z, 040300Z AND 040900Z.
http://www.bom.gov.au/fwo/IDW60284.png?1512024625967