SIO: Mitchell - Tropical Cyclone

[supercane4867]

15kts 1010mb 13.1S 112.7E

[supercane4867]

Potential Cyclones:

Thunderstorm activity continues in the tropical maritime parts of the Western
Region near the monsoon trough which extends to a weak low is near 12.5S
115.5E. The low is expected to move to the west southwest over
the next few days, but is unlikely to develop into a tropical cyclone during
the outlook period.

Likelihood of this system being a tropical cyclone in the Western Region on:
Friday Low
Saturday Low
Sunday Low

[supercane4867]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.4S
113.0E IS NOW LOCATED NEAR 14.8S 112.2E, APPROXIMATELY 455 NM
NORTH-NORTHWEST OF LEARMONTH, AUSTRALIA. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY SHOWS THE ASSOCIATED CENTRAL DENSE OVERCAST HAS
SIGNIFICANTLY DEEPENED OVER THE PAST 12 HOURS. THE SAME ANIMATION
ALSO SHOWS FORMATIVE BANDING ALONG THE NORTHWEST QUADRANT OF THE
SYSTEM. UPPER LEVEL ANALYSIS INDICATES THIS DISTURBANCE IS UNDER A
RIDGE AXIS IN AN AREA OF WEAK (05-10 KNOT) VERTICAL WIND SHEAR AND
FAVORABLE POLEWARD AND EQUATORWARD OUTFLOW. NUMERIC WEATHER
PREDICTION MODELS CONTINUE TO DEVELOP THIS SYSTEM OVER THE NEXT 24-48
HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. IN
VIEW OF THE IMPROVED ORGANIZATION AND THE ENVIRONMENT EXPECTED TO
REMAIN UNCHANGED, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

[Meow]

It is now Tropical Low 04U. What happened to 01U, 02U and 03U?



AXAU01 APRF 280655
IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0655 UTC 28/12/2012
Name: Tropical Low
Identifier: 04U
Data At: 0600 UTC
Latitude: 15.6S
Longitude: 111.7E
Location Accuracy: within 45 nm [85 km]
Movement Towards: south [189 deg]
Speed of Movement: 7 knots [13 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: T2.0/2.0/D0.5/6HRS
Pressure of outermost isobar: 1004 hPa
Radius of outermost closed isobar: 200 nm [370 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 28/1800: 16.6S 111.2E: 070 [130]: 035 [065]: 995
+24: 29/0600: 17.8S 110.8E: 095 [175]: 040 [075]: 993
+36: 29/1800: 19.3S 110.7E: 115 [210]: 050 [095]: 986
+48: 30/0600: 21.1S 110.6E: 135 [245]: 055 [100]: 982
+60: 30/1800: 23.3S 110.1E: 150 [280]: 045 [085]: 988
+72: 31/0600: 25.6S 109.4E: 170 [320]: 035 [065]: 995
REMARKS:
Convective organisation assocaited with system 04U has greatly improved in the
last 24 hours, likely due to Kelvin wave propagating through the area. However
low level cloud lines are not particularly well organised and there are still
low level squall lines emanating from the convection indicative of convective
downdrafts driven by dry air in the mid levels. Hence it may take a little while
to moisten the mid levels before the system can reach TC intensity.
Ocean heat content is high in the vicinity and shear is less than 20 knots.
Upper divergence currently good to east and southeast. Conditions expected to
remain favourable to very favourable over the next two days before the system
moves over cooler water off the west coast. TPW is favourable, i.e. no dry air
threatening the system. Expect development at D or D+ rate.
Cooler waters south of 20S should begin to weaken the system from early Monday.
Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 28/1300 UTC by Perth TCWC.

[Grifforzer]

It is now Tropical Low 04U. What happened to 01U, 02U and 03U?

WWSO21 ABRF 281313
IDQ20015
Australian Government Bureau of Meteorology
Queensland
Tropical Cyclone Warning Centre

SATELLITE ANALYSIS BULLETIN
1313 UTC 28 December 2012
Tropical Low 05F / 03U / 94P
281300UTC
11.1S 160.2E
Analysis based on: MTSAT IR 281130UTC, ASCAT 1111UTC
Latitude Detection Sum: 3
Longitude Detection Sum: 9
T2.5/2.5/D1.0/24HRS
Curved band pattern - 0.4 wrap on log 10 spiral. DT is 2.5. MET is 2.0. Final T
based on DT.
WHR BRISBANE

[euro6208]

WTXS21 PGTW 280930
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
110 NM EITHER SIDE OF A LINE FROM 15.1S 111.8E TO 20.5S 109.8E
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 25 TO 30 KNOTS. METSAT IMAGERY
AT 280630Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.3S 111.7E. THE SYSTEM IS MOVING SOUTHWESTWARD AT 05
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.8S
112.2E IS NOW LOCATED NEAR 15.3S 111.7E, APPROXIMATELY 435 NM
NORTH-NORTHWEST OF LEARMONTH, AUSTRALIA. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY SHOWS A SIGNIFICANT INCREASE IN DEEP CONVECTION
OVER THE PAST 12 HOURS, WITH FORMATIVE BANDING DEVELOPING AROUND THE
PERIPHERY OF THE SYSTEM EVIDENT IN A 280510Z TRMM MICROWAVE IMAGE.
THIS DISTURBANCE LIES JUST TO THE WEST OF AN UPPER LEVEL ANTICYCLONE
CENTER, DIRECTLY BENEATH A SUBTROPICAL RIDGE AXIS IN AN AREA OF
LIGHT (10 TO 15 KNOT) VERTICAL WIND SHEAR AND FAVORABLE DUAL CHANNEL
OUTFLOW. A 280201Z PARTIAL ASCAT PASS SHOWS 25 KNOT NORTHERLY WINDS
ALONG THE EASTERN PERIPHERY OF THE DISTURBANCE, WITH A FEW 30 KNOT
EAST-NORTHEASTERLY WINDS IN THE SOUTHEAST QUADRANT. NUMERICAL MODEL
GUIDANCE DEVELOPS THIS SYSTEM OVER THE NEXT 24 TO 36 HOURS AS IT
CONTINUES TO MOVE TO THE SOUTH-SOUTHWEST. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1004 MB. DUE TO INCREASING CONSOLIDATION OF THE
LLCC AND A FAVORABLE UPPER LEVEL ENVIRONMENT, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
290930Z.//
NNNN

[euro6208]

TPXS10 PGTW 281516 COR

A. TROPICAL DISTURBANCE 95S (NW OF AUSTRALIA)

B. 28/1432Z

C. 15.8S

D. 111.0E

E. FIVE/MTSAT

F. T2.0/2.0/D0.5/21HRS STT: S0.0/03HRS

G. IR/EIR

H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAP OF .35 ON LOG10
SPIRAL YIELDS A DT OF 2.0. PT AND MET AGREE. DBO DT. CORRECTED
LONGITUDE IN LINE D.

I. ADDITIONAL POSITIONS:
28/0954Z 15.5S 111.2E SSMS
28/1224Z 15.7S 111.1E SSMS


UEHARA

[Meow]

They still do not want to name a tropical cyclone with 10-min maximum sustained winds at 35 knots.

AXAU01 APRF 281900
IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1900 UTC 28/12/2012
Name: Tropical Low
Identifier: 04U
Data At: 1800 UTC
Latitude: 16.1S
Longitude: 110.7E
Location Accuracy: within 35 nm [65 km]
Movement Towards: southwest [223 deg]
Speed of Movement: 7 knots [13 km/h]
Maximum 10-Minute Wind: 35 knots [65 km/h]
Maximum 3-Second Wind Gust: 50 knots [95 km/h]
Central Pressure: 998 hPa
Radius of 34-knot winds NE quadrant:
Radius of 34-knot winds SE quadrant: 120 nm [220 km]
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: 100 nm [185 km]
Dvorak Intensity Code: T2.5/2.5/D1.0/24HRS
Pressure of outermost isobar: 1006 hPa
Radius of outermost closed isobar: 300 nm [555 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 29/0600: 17.1S 110.2E: 065 [120]: 040 [075]: 994
+24: 29/1800: 18.5S 110.1E: 090 [165]: 050 [095]: 988
+36: 30/0600: 20.3S 109.8E: 110 [200]: 055 [100]: 982
+48: 30/1800: 22.2S 109.1E: 130 [235]: 050 [095]: 985
+60: 31/0600: 24.3S 108.4E: 150 [275]: 045 [085]: 988
+72: 31/1800: 26.1S 108.1E: 165 [310]: 040 [075]: 990
REMARKS:
Convective organisation associated with system 04U has improved in the
last 24 hours. This is likely due to a Kelvin wave propagating through the area.
Mean winds of 35 knots in the southeast quadrant only. Expect mean winds of 30
knots in the remaining quadrants.
Ocean heat content is high in the vicinity and shear is less than 15 knots.
Upper divergence currently good to east and southeast. Conditions expected to
remain favourable to very favourable over the next two days before the system
moves over cooler water off the west coast. TPW is favourable, i.e. no dry air
threatening the system. Expect development at D or D+ rate.
Cooler waters south of 20S should begin to weaken the system from early Monday.
Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 29/0100 UTC by Perth TCWC.

[supercane4867]

TROPICAL CYCLONE 06S (SIX) WARNING NR 001
WTXS31 PGTW 282100
1. TROPICAL CYCLONE 06S (SIX) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
281800Z --- NEAR 16.3S 110.7E
MOVEMENT PAST SIX HOURS - 205 DEGREES AT 07 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
REPEAT POSIT: 16.3S 110.7E
---
FORECASTS:
12 HRS, VALID AT:
290600Z --- 17.6S 110.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 195 DEG/ 09 KTS
---
24 HRS, VALID AT:
291800Z --- 19.3S 109.9E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
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 - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 190 DEG/ 09 KTS
---
36 HRS, VALID AT:
300600Z --- 21.0S 109.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 195 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
301800Z --- 22.8S 109.0E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 200 DEG/ 08 KTS
---
72 HRS, VALID AT:
311800Z --- 25.6S 107.8E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
282100Z POSITION NEAR 16.6S 110.6E.

THIS WARNING SUPERSEDES AND CANCELS REF A, JOINT TYPHOON WRNCEN
PEARL HARBOR HI 280930Z DEC 12 TROPICAL CYCLONE FORMATION ALERT
(WTXS21 PGTW 280930 )
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 281800Z IS 10 FEET.
NEXT WARNINGS AT 290300Z, 290900Z, 291500Z AND 292100Z.
//

[P.K.]

They still do not want to name a tropical cyclone with 10-min maximum sustained winds at 35 knots.

They don't consider it a TC until 34kt mean winds extend more than half way round the centre. At the moment these winds are confined to one quad, hence not being named.

[HURAKAN]

TC Mitchell

[euro6208]

1. TROPICAL CYCLONE 06S (MITCHELL) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
291200Z --- NEAR 18.9S 110.2E
MOVEMENT PAST SIX HOURS - 185 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
050 NM NORTHWEST QUADRANT
REPEAT POSIT: 18.9S 110.2E


REMARKS:
291500Z POSITION NEAR 19.4S 110.1E.
TROPICAL CYCLONE (TC) 06S (MITCHELL), LOCATED APPROXIMATELY 290 NM
NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWARD
AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
SATELLITE IMAGERY (IR) DEPICTS THE LOW-LEVEL CIRCULATION CENTER
HAS BECOME ELONGATED AND CONVECTION HAS WEAKENED WITH A SMALL COLD
DENSE OVERCAST FEATURE BEGINNING TO FORM. THE INITIAL POSITION IS
BASED ON THE IR LOOP AND SATELLITE FIXES FROM MULTIPLE REPORTING
AGENCIES. THE INITIAL INTENSITY IS ASSESSED AT 40 KNOTS BASED ON THE
WEAKENING TREND OBSERVED IN THE IR AND DECREASING DVORAK INTENSITY
ESTIMATES FROM ALL AGENCIES. UPPER-LEVEL ANALYSIS REVEALS TC 06S HAS
MAINTAINED POLEWARD OUTFLOW INTO THE SUBTROPICAL JET LOCATED OVER
CENTRAL AUSTRALIA BUT THE UPPER-LEVEL LOW WHICH WAS ENHANCING THIS
OUTFLOW HAS FILLED. TC 06S IS FORECAST TO CONTINUE
TRACKING SOUTH-SOUTHWESTWARD THROUGH THE FORECAST PERIOD ALONG THE
WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE THAT IS MERIDIONALLY
ORIENTED ALONG THE WESTERN COAST OF AUSTRALIA. DYNAMIC MODEL
GUIDANCE IS IN GOOD AGREEMENT LENDING TO HIGH CONFIDENCE IN THE JTWC
TRACK FORECAST, WHICH IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS. TC 06S IS FORECAST TO MAINTAIN INTENSITY FOR THE NEXT 12
HOURS AND THEN SLOWLY WEAKEN AS COOLER SEA SURFACE TEMPERATURES (24
TO 26 DEGREES CELSIUS) ARE ENCOUNTERED SOUTH OF 20S. TC 06S IS
EXPECTED TO DISSIPATE BY TAU 48 DUE TO THE DECREASING ENVIRONMENTAL
CONDITIONS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 291200Z IS 17 FEET.
NEXT WARNINGS AT 300300Z AND 301500Z.//
NNNN

[Grifforzer]

Only has gale force winds in one southern quadrant downgraded to Tropical Low

IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0156 UTC 30/12/2012
Name: Ex-Tropical Cyclone Mitchell
Identifier: 04U
Data At: 0000 UTC
Latitude: 21.1S
Longitude: 110.2E
Location Accuracy: within 30 nm [55 km]
Movement Towards: south [175 deg]
Speed of Movement: 11 knots [20 km/h]
Maximum 10-Minute Wind: 35 knots [65 km/h]
Maximum 3-Second Wind Gust: 50 knots [95 km/h]
Central Pressure: 995 hPa
Radius of 34-knot winds NE quadrant:
Radius of 34-knot winds SE quadrant: 90 nm [165 km]
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: T1.5/2.5/W1.5/24HRS STT:W0.5/6HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 120 nm [220 km]
Storm Depth: Medium
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 30/1200: 23.0S 109.4E: 055 [100]: 035 [065]: 993
+24: 31/0000: 25.3S 108.4E: 080 [145]: 030 [055]: 996
+36: 31/1200: 27.6S 108.2E: 100 [180]: 030 [055]: 994
+48: 01/0000: 29.5S 109.1E: 120 [220]: 025 [045]: 997
+60: 01/1200: 31.5S 111.1E: 140 [255]: 025 [045]: 996
+72: 02/0000: : : :
REMARKS:
Convection and organisation of Ex-Tropical Cyclone Mitchell has continued to
weaken in the last 6-12 hours as it moves south into an unfavourable region of
cooler ocean temperatures. Weakening may also have been influenced by dry air to
the west which appears to be wrapping into the centre. Dvorak FT has reduced to
1.5 based on the reduced area of convection. CI has been reduced to 2.5 with
weakening constraints. Recent Ascat and surface observations indicate gales
persisting in the southeastern quadrant.

ADT is showing a weakening trend but is a little higher, perhaps influenced by
an interpolated forecast position that is too far south. AMSU intensity
estimates also seem to have a high bias.

The system is currently in a moderately sheared environment and is expected to
continue to weaken as it moves further south. Gales may persist in the southeast
quadrant during Sunday.

A consistent south to southwesterly track is likely in the next 24 to 48 hours.

[galaxy401]

This was kinda like a storm back in 2009 that was originally a TC but downgraded to a Tropical Low post analysis due to gale force winds in only one quadrant.

[euro6208]

1. TROPICAL CYCLONE 06S (MITCHELL) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
300600Z --- NEAR 22.6S 110.0E
MOVEMENT PAST SIX HOURS - 185 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 060 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: 22.6S 110.0E

REMARKS:
300900Z POSITION NEAR 23.2S 109.8E.
TROPICAL CYCLONE (TC) 06S (MITCHELL), LOCATED APPROXIMATELY 225 NM
WEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWARD AT 13 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
INDICATES THAT TC 06S HAS CONTINUED TO WEAKEN RAPIDLY WITH LIMITED
SHALLOW CONVECTION AND THE LOW LEVEL CIRCULATION CENTER HAS NOW
BECOME FULLY EXPOSED. A 300457Z TRMM 85 GHZ MICROWAVE IMAGE CONCURS
WITH THE MSI AND ADDITIONALLY SHOWS SOME DRY CONTINENTAL AIR BEING
PULLED INTO THE SYSTEM, WHICH WILL FURTHER WEAKEN TC 06S. THE
INITIAL INTENSITY OF 35 KNOTS IS BASED UPON FALLING DVORAK INTENSITY
ESTIMATES AND THE OVERALL WEAKENING TREND SEEN IN IMAGERY. THERE IS
GOOD CONFIDENCE IN THE INITIAL POSITION BASED ON THE TRMM IMAGE AND
THE MSI LOOP. TC 06S IS TRACKING SOUTHWARD TO SOUTH-SOUTHWESTWARD
ALONG THE WESTERN PERIPHERY OF A DEEP SUBTROPICAL RIDGE, WHICH IS
ENTRENCHED OVER WESTERN AUSTRALIA. TC 06S IS FORECAST TO WEAKEN
THROUGHOUT THE FORECAST PERIOD AND SHOULD DISSIPATE BELOW WARNING
THRESHOLD BY TAU 12 AS IT TRACKS OVER COOL SST (LESS THAN 24C) AND
ENCOUNTERS INCREASING VERTICAL WIND SHEAR. THIS IS THE FINAL WARNING
ON THIS SYSTEM BY THE JOINT TYPHOON WRNCEN PEARL HARBOR HI. THE
SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 300600Z IS 15 FEET.//
NNNN

[Iune]

There've been several storms that were downgraded post-season; recent examples include Ken ('03-'04), Isobel & Odette ('06-'07), Gabrielle ('08-'09), and Angrekk ('10-'11).

[Hurricane_Luis]

Ex-Tropical Cyclone Mitchell