SIO: ALESSIA - Ex-Tropical Cyclone

[supercane4867]

Potential Cyclones:

A trough lies across waters south of the Indonesian Archipelago. There is a
very weak low near 09S 112E, which is about 700km east northeast of Christmas
Island. The low is expected to move east southeast over the next few days. In
the short term, conditions are unfavourable for development. Conditions improve
a little on Friday and Saturday and thus there is a slight chance of
development on Friday or over the weekend.

Likelihood of this system being a tropical cyclone in the Western Region on:
Wednesday Very Low
Thursday Very Low
Friday Low

[jaguarjace]

Finally something to watch above W.A.

[supercane4867]

Finally something to watch above W.A.

GFS had been showing development few days ago but dropped the system now
BOM model still has a depression moving toward WA coast

[Grifforzer]

Tropical Cyclone Warning Center Perth
1:54 PM WST November 20 2013

A trough lies across waters south of the Indonesian Archipelago. A developing low near 10S 113E is expected to move east-southeast over the next few days. Conditions are becoming more favorable as the system moves over warmer 29C ocean waters.

Even if the system doesn't develop into a tropical cyclone, a period of strong to possibly gale force winds, locally higher seas and squally showers could impact Browse Basin and Kimberley coast on Saturday.

Thursday: Very Low
Friday: Low
Saturday: Low

[jaguarjace]

Australian Government Bureau of Meteorology
Western Australia

Updated Tropical Cyclone Day Outlook for Western Region
Issued at 4:52 pm WST on Wednesday 20 November 2013.

Potential Cyclones:
A trough lies across waters south of the Indonesian Archipelago. At 2pm Western
Standard Time a low was situated near 11S 113E. This low is expected to move
steadily east southeast over the next few days, and pass north of the Kimberley
coast over the weekend. This low has shown some development over the last 24
hours and its structure and much of its thunderstorm activity has been
maintained during the less favourable daylight hours. Conditions are moderately
favourable for development over the next few days.

Even if the system does not develop into a tropical cyclone, a period of strong
to possibly gale force winds, locally higher seas and squally showers is likely
as the system moves through waters just north of the Kimberley.

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


Not an official product from SSD. I created this product for informational purposes.

[euro6208]

AN AREA OF CONVECTION HAS PERSISTED NEAR 10.6S 113.7E,
APPROXIMATELY 790 NM NORTH OF LEARMONTH, AUSTRALIA. RECENT ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS PERSISTENT DEEP CONVECTION
OVER A DEVELOPING LOW-LEVEL CIRCULATION CENTER (LLCC). UNFORTUNATELY
RECENT SCATTEROMETRY PASSES MISSED THE AREA BUT A 200148Z AMSU-B
PASS REVEALS GOOD SPIRAL BANDING STRUCTURE IN THE MID-LEVELS WITH A
BROADER APPEARANCE TO THE LLCC. UPPER-LEVEL ANALYSIS INDICATES THE
DISTURBANCE IS LOCATED A COUPLE DEGREES EQUATORWARD OF THE
SUBTROPICAL RIDGE AXIS UNDER 15-20 KNOTS OF VERTICAL WIND SHEAR.
DEEP CONVECTION SEEMS TO BE MAINTAINED BY GOOD POLEWARD OUTFLOW
WHICH CONNECTS INTO THE MID-LATITUDE WESTERLIES. SEA SURFACE
TEMPERATURES ARE FAVORABLE FOR DEVELOPMENT, RANGING FROM 29-31
DEGREES CELSIUS. INTERESTINGLY ENOUGH THERE SEEMS TO BE A COLD
POCKET OF OCEAN HEAT CONTENT LOCATED RIGHT BENEATH THE DISTURBANCE.
MOST MODELS MAINTAIN A WEAK CIRCULATION WHICH TRAVERSES THE NORTH
AUSTRALIAN BASIN DURING THE NEXT SEVERAL DAYS BUT CURRENTLY THERE
ARE NO INDICATIONS OF STRONG DEVELOPMENT IN THE NEAR-TERM. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. THE POTENTIAL FOR
THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS LOW.

[jaguarjace]

AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

TROPICAL CYCLONE FORECAST TRACK MAP
Tropical Low
Issued at 2:15 pm WST Thursday 21 November 2013.



Remarks:
The low is not expected to cause gales during Thursday or Friday. Gales may develop along the north
Kimberley coast on Saturday as the system approaches the coast. Overnight Saturday into Sunday it is likely
to brush the northern Kimberley coast. During Sunday it is likely to weaken as it approaches the west coast of
the Top End.

Rainfall from this system is likely to be confined to coastal areas. Even in coastal areas, rainfall totals are
expected to be less than is typical with a tropical low or cyclone.


NOV 20 1813 UTC - NOV 21 0530 UTC Floater Loops:
>WATER VAPOR Enhancement
>RGB Enhancement
>RAINBOW Enhancement
>RBTOP Enhancement

[jaguarjace]

JOINT TYPHOON WARNING CENTER PEARL HARBOR HAWAII
SIGNIFICANT TROPICAL WEATHER ADVISORY

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.6S
113.7E, IS NOW LOCATED NEAR 11.3S 113.3E, APPROXIMATELY 655 NM NORTH
OF LEARMONTH, AUSTRALIA. RECENT ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A DEVELOPING LOW-
LEVEL CIRCULATION CENTER. A RECENT 201327Z ASCAT PASS SHOWS AN
ELONGATED CIRCULATION ORIENTED ALONG A NORTHWEST-SOUTHEAST AXIS WITH
WIND SPEEDS RANGING FROM 20 TO 25 KNOTS. UPPER-LEVEL ANALYSIS
INDICATES THE DISTURBANCE IS LOCATED A COUPLE DEGREES EQUATORWARD OF
THE SUBTROPICAL RIDGE AXIS UNDER 15-20 KNOTS OF VERTICAL WIND SHEAR.
DEEP CONVECTION SEEMS TO BE MAINTAINED BY GOOD POLEWARD OUTFLOW
WHICH CONNECTS INTO THE MID-LATITUDE WESTERLIES. SEA SURFACE
TEMPERATURES ARE FAVORABLE FOR DEVELOPMENT, RANGING FROM 29 TO 31
DEGREES CELSIUS. MOST MODELS MAINTAIN A WEAK CIRCULATION, WHICH
TRAVERSES NORTHERN AUSTRALIAN OVER THE NEXT SEVERAL DAYS BUT DO NOT
INDICATE STRONG DEVELOPMENT IN THE NEAR-TERM. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.

[stormkite]

It's early in the season for the monsoon trough to form over the northwest. Its good to see the AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY TROPICAL CYCLONE FORECAST TRACK MAP being used and not the usual saturation of JTWC FORECASTS.

[euro6208]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 11.3S
113.3E, IS NOW LOCATED NEAR 13.6S 118.2E, APPROXIMATELY 350 NM
NORTHWEST OF BROOME, AUSTRALIA. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A DEVELOPING LOW
LEVEL CIRCULATION CENTER (LLCC). A RECENT 211400Z METOP-B 89 GHZ
MICROWAVE PASS SHOWS THE LLCC HAS BECOME MORE SYMMETRIC OVER THE
PAST 24 HOURS, BUT INDICATES DEEP CONVECTION REMAINS ALONG THE
SOUTHERN PERIPHERY UNDER THE INFLUENCE OF MODERATE LEVELS OF
VERTICAL WIND SHEAR (15 TO 20 KNOTS). SEA SURFACE TEMPERATURES ARE
FAVORABLE FOR DEVELOPMENT, RANGING FROM 29 TO 31 DEGREES CELSIUS.
MOST MODELS MAINTAIN A WEAK CIRCULATION, WHICH TRAVERSES NORTHERN
AUSTRALIA OVER THE NEXT SEVERAL DAYS BUT DO NOT INDICATE STRONG
DEVELOPMENT IN THE NEAR-TERM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1003 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.

[HurricaneBill]

It's early in the season for the monsoon trough to form over the northwest. Its good to see the AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY TROPICAL CYCLONE FORECAST TRACK MAP being used and not the usual saturation of JTWC FORECASTS.

We always use the BoM maps for this region. Yes, we also post JTWC maps. Some people like to compare/contrast between agencies.

[jaguarjace]

AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

TROPICAL CYCLONE FORECAST TRACK MAP
Tropical Low
Issued at 8:43 am WST Friday 22 November 2013.



Remarks:
The low is not expected to cause gales over the northern Kimberley during Friday. Gales may develop along
the northern Kimberley coast on Saturday as the system approaches. Overnight Saturday into Sunday it is
likely to brush the northern Kimberley coast. During Sunday it is likely to weaken as it approaches the west
coast of the Top End.

Rainfall from this system is likely to be confined to coastal areas. Even in coastal areas, rainfall totals are
expected to be less than is typical with a tropical low or cyclone.


NOV 21 1430 UTC - NOV 21 0030 UTC Floater Loops:
>WATER VAPOR Enhancement
>RGB Enhancement
>RAINBOW Enhancement
>RBTOP Enhancement

[supercane4867]

TPXS10 PGTW 220013
A. TROPICAL DISTURBANCE 90S (SE OF JAVA)
B. 21/2330Z
C. 14.6S
D. 119.0E
E. FIVE/MTSAT
F. T2.0/2.0 STT: S0.0/03HRS
G. IR/EIR
H. REMARKS: 38A/PBO SBC/ANMTN. .45 WRAP YIELDS A DT OF 2.5. PT
WAS 2.0; MET WAS N/A. DBO PT AS EXPANSIVE CONVECTION OVER THE
AREA MAKES A HIGH CONFIDENCE WRAP DIFFICULT; ALSO FOLLOWING
CONSTRAINTS (CHANGE OF 0.5 IN 6HRS).
I. ADDITIONAL POSITIONS: NONE

[stormkite]

It's early in the season for the monsoon trough to form over the northwest. Its good to see the AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY TROPICAL CYCLONE FORECAST TRACK MAP being used and not the usual saturation of JTWC FORECASTS.

We always use the BoM maps for this region. Yes, we also post JTWC maps. Some people like to compare/contrast between agencies.

system.works off of gust speeds and a 10 min sustained wind speed not the 1 min JTWC .


Australian scale of cyclone intensity
▪ Table
Australian scale of cyclone intensity
category wind speed damage
km/hr mph
1 63-90 39-56 some damage to crops, trees, caravans (mobile homes); gusts to 125 km/hr (78 mph)
2 91-125 57-78 heavy damage to crops, significant damage to caravans; gusts of 125-170 km/hr (78-105 mph)
3* 126-165 79-102 some caravans destroyed; some roofs and structures damaged; gusts of 170-225 km/hr (105-140 mph)
4 166-226 103-140 significant damage to roofs and structures; caravans destroyed; gusts of 225-280 km/hr (140-174 mph)
5 >226 >140 widespread destruction; gusts greater than 280 km/hr (174 mph)

[jaguarjace]

JOINT TYPHOON WARNING CENTER PEARL HARBOR HAWAII
TROPICAL CYCLONE WARNING GRAPHIC
SIGNIFICANT TROPICAL WEATHER ADVISORY



REMARKS:
220900Z POSITION NEAR 14.5S 120.5E.
TROPICAL CYCLONE 02S (TWO), LOCATED APPROXIMATELY 237 NM NORTH-
NORTHWESTWARD OF BROOME, AUSTRALIA, HAS TRACKED EAST-SOUTHEASTWARD AT
14 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS THE SYSTEM HAS SIGNIFICANTLY DEEPENED AS FORMATIVE
BANDS WRAPPED TIGHTER INTO THE LOW LEVEL CIRCULATION CENTER THAT HAS
BECOME BETTER-DEFINED. THE INITIAL POSITION AND INTENSITY ARE BASED
ON CLOSELY-SPACED DVORAK FIXES FROM PGTW, APRF, AND KNES. UPPER LEVEL
ANALYSIS INDICATES THE SYSTEM IS UNDER THE RIDGE AXIS IN AN AREA OF
LOW (05-10 KNOT) VERTICAL WIND SHEAR AND GOOD RADIAL OUTFLOW. THE
CYCLONE IS TRACKING ALONG THE OUTER BOUNDARY OF A NEAR-EQUATORIAL
RIDGE TO THE NORTHEAST AND IS EXPECTED TO MOVE ON A GENERALLY
EASTWARD PATTERN TOWARDS DARWIN. THE SYSTEM WILL CONTINUE TO
INTENSIFY OVER THE NEXT 36 HOURS AS UPPER LEVEL CONDITIONS, IN
ADDITION TO WARM SEA SURFACE TEMPERATURES, PREVAIL. AFTERWARDS, THE
CYCLONE WILL DRAG ACROSS THE SWAMPY TERRAIN OF NORTHERN AUSTRALIA
JUST SOUTH OF DARWIN. INTERACTION WITH THE LANDMASS WILL CAUSE ITS
GRADUAL DECAY AND EVENTUAL DISSIPATION BY TAU 120. THE AVAILABLE
NUMERIC GUIDANCE IS IN FAIR AGREEMENT; HOWEVER, GIVEN THE UNCERTAINTY
OF AN OVER LAND TRACK, THERE IS LOW CONFIDENCE IN THE JTWC TRACK
FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220600Z IS 10 FEET. NEXT
WARNINGS AT 222100Z AND 230900Z. THIS WARNING SUPERSEDES AND CANCELS
REF A (WTXS21 PGTW 212300). //
NNNN

[stormkite]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 11.3S
113.3E, IS NOW LOCATED NEAR 13.6S 118.2E, APPROXIMATELY 350 NM
NORTHWEST OF BROOME, AUSTRALIA. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A DEVELOPING LOW
LEVEL CIRCULATION CENTER (LLCC). A RECENT 211400Z METOP-B 89 GHZ
MICROWAVE PASS SHOWS THE LLCC HAS BECOME MORE SYMMETRIC OVER THE
PAST 24 HOURS, BUT INDICATES DEEP CONVECTION REMAINS ALONG THE
SOUTHERN PERIPHERY UNDER THE INFLUENCE OF MODERATE LEVELS OF
VERTICAL WIND SHEAR (15 TO 20 KNOTS). SEA SURFACE TEMPERATURES ARE
FAVORABLE FOR DEVELOPMENT, RANGING FROM 29 TO 31 DEGREES CELSIUS.
MOST MODELS MAINTAIN A WEAK CIRCULATION, WHICH TRAVERSES NORTHERN
AUSTRALIA OVER THE NEXT SEVERAL DAYS BUT DO NOT INDICATE STRONG
DEVELOPMENT IN THE NEAR-TERM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1003 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.

WHEN you use official forecast snippets like this one above you should give the credit to the
authors.

[euro6208]

20131122 1130 -14.6 -121.1 T3.0/3.0 02S NONAME

[jaguarjace]

AUSTRALIAN GOVERNMENT BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

TROPICAL CYCLONE FORECAST TRACK MAP
Tropical Cyclone Alessia
Issued at 8:56 pm WST Friday 22 November 2013.



Remarks:
Tropical Cyclone Alessia has developed northwest of the Kimberley coast. Gales may develop along the
northern Kimberley coast on Saturday as the system approaches. Overnight Saturday into Sunday it is likely
to brush the northern Kimberley coast. During Sunday it is likely to weaken as it approaches the west coast of
the Top End.

[euro6208]

JTWC has Alessia up to 45 knots!

02S ALESSIA 131122 1200 14.5S 121.6E SHEM 45 989

[Hurricane_Luis]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 11.3S
113.3E, IS NOW LOCATED NEAR 13.6S 118.2E, APPROXIMATELY 350 NM
NORTHWEST OF BROOME, AUSTRALIA. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS PERSISTENT DEEP CONVECTION OVER A DEVELOPING LOW
LEVEL CIRCULATION CENTER (LLCC). A RECENT 211400Z METOP-B 89 GHZ
MICROWAVE PASS SHOWS THE LLCC HAS BECOME MORE SYMMETRIC OVER THE
PAST 24 HOURS, BUT INDICATES DEEP CONVECTION REMAINS ALONG THE
SOUTHERN PERIPHERY UNDER THE INFLUENCE OF MODERATE LEVELS OF
VERTICAL WIND SHEAR (15 TO 20 KNOTS). SEA SURFACE TEMPERATURES ARE
FAVORABLE FOR DEVELOPMENT, RANGING FROM 29 TO 31 DEGREES CELSIUS.
MOST MODELS MAINTAIN A WEAK CIRCULATION, WHICH TRAVERSES NORTHERN
AUSTRALIA OVER THE NEXT SEVERAL DAYS BUT DO NOT INDICATE STRONG
DEVELOPMENT IN THE NEAR-TERM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1003 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.

WHEN you use official forecast snippets like this one above you should give the credit to the
authors.

Stormkite, I do agree with you. But most know that this "snippet" comes from the JTWC.