SIO: TROPICAL CYCLONE SEAN / TC 24S (JTWC)

[KWT]

Looks like it should slowly weaken from here on according to that forecast...

[HURAKAN]

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0110 UTC 25/04/2010
Name: Tropical Cyclone Sean
Identifier: 13U
Data At: 0000 UTC
Latitude: 17.5S
Longitude: 111.3E
Location Accuracy: within 20 nm [35 km]
Movement Towards: west southwest [251 deg]
Speed of Movement: 6 knots [11 km/h]
Maximum 10-Minute Wind: 40 knots [75 km/h]
Maximum 3-Second Wind Gust: 55 knots [100 km/h]
Central Pressure: 996 hPa
Radius of 34-knot winds NE quadrant: 45 nm [85 km]
Radius of 34-knot winds SE quadrant: 45 nm [85 km]
Radius of 34-knot winds SW quadrant: 45 nm [85 km]
Radius of 34-knot winds NW quadrant: 45 nm [85 km]
Radius of 48-knot winds NE quadrant:
Radius of 48-knot winds SE quadrant:
Radius of 48-knot winds SW quadrant:
Radius of 48-knot winds NW quadrant:
Radius of 64-knot winds:
Radius of Maximum Winds: 15 nm [30 km]
Dvorak Intensity Code: T2.5/3.0/W1.5/24HRS
Pressure of outermost isobar: 1006 hPa
Radius of outermost closed isobar: 100 nm [185 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 25/1200: 17.7S 110.0E: 045 [085]: 030 [055]: 1000
+24: 26/0000: 17.8S 107.9E: 075 [140]: 030 [055]: 1000
+36: 26/1200: 17.8S 104.5E: 105 [195]: 030 [055]: 1004
+48: 27/0000: 17.9S 100.9E: 135 [250]: 030 [055]: 1006
+60: 27/1200: 17.7S 97.8E: 165 [305]: 030 [055]: 1006
+72: 28/0000: 16.8S 95.7E: 195 [360]: 030 [055]: 1008
REMARKS:
Tropical Cyclone Sean has weakened considerably overnight due to moderate to
strong NW shear. Latest UW-CIMSS shear analysis at 00 UTC indicates NW shear
between 25 and 30 knots.

The centre was relocated using the 2330 UTC visible image and microwave imagery
overnight. The visible image showed a fully exposed LLCC with no deep convection
nearby.

Dvorak: Shear pattern gives DT of 1.0 to 1.5. MET is 2.5 based on W+ trend and
PAT is 2.0. FT constrained to 2.5 and CI held at 3.0.

The system is likely to weaken below tropical cyclone intensity by 0600 UTC with
the low level centre expected to move in a general westerly direction.


Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 25/0700 UTC by Perth TCWC.

[HURAKAN]

Poof!

[HURAKAN]

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0705 UTC 25/04/2010
Name: Ex-Tropical Cyclone Sean
Identifier: 13U
Data At: 0600 UTC
Latitude: 18.1S
Longitude: 110.5E
Location Accuracy: within 15 nm [30 km]
Movement Towards: west southwest [237 deg]
Speed of Movement: 10 knots [18 km/h]
Maximum 10-Minute Wind: 30 knots [55 km/h]
Maximum 3-Second Wind Gust: 45 knots [85 km/h]
Central Pressure: 1000 hPa
Radius of 34-knot winds NE quadrant:
Radius of 34-knot winds SE quadrant:
Radius of 34-knot winds SW quadrant:
Radius of 34-knot winds NW quadrant:
Radius of 48-knot winds NE quadrant:
Radius of 48-knot winds SE quadrant:
Radius of 48-knot winds SW quadrant:
Radius of 48-knot winds NW quadrant:
Radius of 64-knot winds:
Radius of Maximum Winds:
Dvorak Intensity Code: T2.0/2.5/W1.5/24HRS
Pressure of outermost isobar: 1008 hPa
Radius of outermost closed isobar: 150 nm [280 km]
Storm Depth: Medium
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 25/1800: 18.5S 108.5E: 045 [085]: 030 [055]: 1002
+24: 26/0600: 18.5S 105.7E: 075 [140]: 030 [055]: 1004
+36: 26/1800: 18.5S 102.1E: 105 [195]: 030 [055]: 1006
+48: 27/0600: 18.5S 98.8E: 135 [250]: 030 [055]: 1006
+60: 27/1800: 18.0S 96.2E: 165 [305]: 030 [055]: 1008
+72: 28/0600: 17.0S 94.3E: 195 [360]: 030 [055]: 1008
REMARKS:
Ex Tropical Cyclone Sean has weakened below cyclone intensity under strong NW
shear. Latest UW-CIMSS shear analysis at 06 UTC indicates NW shear between 25
and 30 knots. The low level circulation centre is fully exposed on visible
imagery with minimal convection nearby.

Dvorak: Shear pattern gives DT of 1.0 to 1.5. MET is 2.0 based on W+ trend and
PAT is 2.0. FT is now 2.0 with CI of 2.5.

The low level circulation centre is expected to track generally westwards under
the influence of low level easterly winds.

Copyright Commonwealth of Australia
==
There will be no further bulletins for this system unless it reintensifies.

[HURAKAN]

Latest

[HURAKAN]

WTXS31 PGTW 250300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 24S (SEAN) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 24S (SEAN) WARNING NR 006
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
250000Z --- NEAR 17.5S 111.3E
MOVEMENT PAST SIX HOURS - 260 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 025 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
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
REPEAT POSIT: 17.5S 111.3E
---
FORECASTS:
12 HRS, VALID AT:
251200Z --- 17.5S 109.6E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 24 HR POSIT: 275 DEG/ 10 KTS
---
24 HRS, VALID AT:
260000Z --- 17.3S 107.5E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
250300Z POSITION NEAR 17.5S 110.9E.
TROPICAL CYCLONE (TC) 24S (SEAN), LOCATED APPROXIMATELY 325 NM NORTH-
NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED WESTWARD AT 08 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
REVEALS A FULLY EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH
DISSIPATING CONVECTION SHEARED TO THE SOUTHEAST. OVER THE PAST 12
HOURS, TC SEAN HAS WEAKENED BY 15 KNOTS DUE TO UNFAVORABLE VERTICAL
WIND SHEAR ASSOCIATED WITH A MID-LATITUDE TROUGH WEST OF THE LLCC.
THE CURRENT INTENSITY OF 35 KNOTS IS BASED ON DECLINING DVORAK
ESTIMATES OF 1.5/2.5 FROM PGTW AND KNES AND IS SUPPORTED BY A 13-
HOUR OLD ASCAT PASS (241350Z) WHICH DEPICTED A MAXIMUM OF 35-KNOT
WINDS. AS THE SYSTEM HAS WEAKENED, IT HAS SHIFTED TO A SHALLOW
STEERING LEVEL AND IS EXPECTED TO CONTINUE TRACKING WESTWARD WITH
THE LOW LEVEL FLOW OVER THE NEXT DAY WHILE DISSIPATING AS A
SIGNIFICANT TROPICAL CYCLONE. THIS IS THE FINAL WARNING ON THIS
SYSTEM BY THE JOINT TYPHOON WARNING CENTER (NAVMARFCSTCEN). THE
SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 250000Z IS 17 FEET.//
NNNN

[thetruesms]

Goodbye, my namesake! I have to admit that I know little about Indian Ocean systems, so this was a fun thread to observe