NW Australia: FREDDY - Tropical Cyclone : Discussion

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Re: NW Australia: FREDDY - Tropical Cyclone : Discussion

#41 Postby HURAKAN » Sat Feb 07, 2009 10:54 pm

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by DARWIN TROPICAL CYCLONE WARNING CENTRE
at: 0255 UTC 08/02/2009
Name: Tropical Cyclone Freddy
Data At: 0000 UTC
Latitude: 15.9S
Longitude: 110.4E
Location Accuracy: within 50 nm [95 km]
Movement Towards: west [279 deg]
Speed of Movement: 6 knots [12 km/h]
Maximum 10-Minute Wind: 50 knots [95 km/h]
Maximum 3-Second Wind Gust: 70 knots [130 km/h]
Central Pressure: 983 hPa
Radius of 34-knot winds NE quadrant: 50 nm [95 km]
Radius of 34-knot winds SE quadrant: 50 nm [95 km]
Radius of 34-knot winds SW quadrant: 150 nm [280 km]
Radius of 34-knot winds NW quadrant: 150 nm [280 km]
Radius of 48-knot winds NE quadrant: 30 nm [55 km]
Radius of 48-knot winds SE quadrant: 30 nm [55 km]
Radius of 48-knot winds SW quadrant: 30 nm [55 km]
Radius of 48-knot winds NW quadrant: 30 nm [55 km]
Radius of 64-knot winds:
Radius of Maximum Winds: 20 nm [37 km]
Dvorak Intensity Code: T3.5/3.5/D0.5/24HRS
Pressure of outermost isobar: 1000 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: 08/1200: 16.5S 109.1E: 080 [150]: 050 [095]: 984
+24: 09/0000: 17.1S 107.1E: 110 [205]: 055 [100]: 981
+36: 09/1200: 17.9S 105.0E: 140 [265]: 050 [095]: 984
+48: 10/0000: 18.5S 102.7E: 175 [325]: 045 [085]: 986
+60: 10/1200: 19.3S 100.6E: 220 [410]: 040 [075]: 989
+72: 11/0000: 19.6S 98.7E: 270 [500]: 035 [065]: 992
REMARKS:
Tropical Cyclone Freddy is located far to the northwest of the Western
Australian mainland.

Fix based on extrapolation from 2057 UTC AMSUB microwave image which indicates
the LLCC is located east of a well-defined mid-level convective ring. Curved
band wraps 0.7 and LLCC under convective cold cloud yields DT/MET/PAT 3.5.

Freddy's convective structure has improved overnight, with good outflow to the
NW and development of banding in the western semicircle. The cyclone is forecast
continue to move to the west southwest during the next 48 hours under the
influence of a mid-level ridge to the southeast. Freddy is expected to intensify
at less than the normal rate due to persistent vertical wind shear. After 24 or
36 hours, wind shear is forecast to decrease, but as the cyclone moves over
cooler sea surface temperatures, it is forecast to gradually weaken.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 08/0700 UTC by Darwin TCWC.

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#42 Postby HURAKAN » Sat Feb 07, 2009 11:03 pm

08/0230 UTC 16.1S 110.0E T3.5/3.5 FREDDY -- Southeast Indian
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#43 Postby Crostorm » Sun Feb 08, 2009 6:17 am

IDW24000
Australian Government Bureau of Meteorology
Western Australia

TROPICAL CYCLONE INFORMATION BULLETIN
Issued at 3:44 pm WDT on Sunday 8 February 2009
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE DARWIN

Tropical Cyclone Freddy (Category 2) was located at 3 pm WDT near 16.2S 109.8E,
that is 900 km northwest of Karratha and 780 km northwest of Exmouth and moving
west at 9 kilometres per hour.
Tropical Cyclone Freddy is located well off the northern WA coast and is
expected to continue to move westwards away from the WA mainland.
Gales are not expected to affect the WA coast.
The next Information Bulletin will be issued at 10 pm WDT.


IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by DARWIN TROPICAL CYCLONE WARNING CENTRE
at: 0658 UTC 08/02/2009
Name: Tropical Cyclone Freddy
Data At: 0600 UTC
Latitude: 16.2S
Longitude: 109.8E
Location Accuracy: within 50 nm [95 km]
Movement Towards: west [264 deg]
Speed of Movement: 5 knots [9 km/h]
Maximum 10-Minute Wind: 50 knots [95 km/h]
Maximum 3-Second Wind Gust: 70 knots [130 km/h]
Central Pressure: 985 hPa
Radius of 34-knot winds NE quadrant: 60 nm [110 km]
Radius of 34-knot winds SE quadrant: 60 nm [110 km]
Radius of 34-knot winds SW quadrant: 150 nm [280 km]
Radius of 34-knot winds NW quadrant: 150 nm [280 km]
Radius of 48-knot winds NE quadrant: 35 nm [65 km]
Radius of 48-knot winds SE quadrant: 35 nm [65 km]
Radius of 48-knot winds SW quadrant: 35 nm [65 km]
Radius of 48-knot winds NW quadrant: 35 nm [65 km]
Radius of 64-knot winds:
Radius of Maximum Winds: 30 nm [55 km]
Dvorak Intensity Code: D3.0/3.5/D0.5/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 250 nm [465 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 08/1800: 16.9S 108.2E: 075 [140]: 055 [100]: 982
+24: 09/0600: 17.6S 106.1E: 095 [175]: 050 [095]: 986
+36: 09/1800: 18.3S 103.8E: 120 [220]: 050 [095]: 985
+48: 10/0600: 19.1S 101.6E: 145 [270]: 045 [085]: 987
+60: 10/1800: 19.8S 99.5E: 175 [325]: 040 [075]: 991
+72: 11/0600: 20.1S 97.7E: 205 [380]: 035 [065]: 993
REMARKS:
Tropical Cyclone Freddy is located far to the northwest of the Western
Australian mainland.

Fix based on 0430 UTC TMI microwave image. Some evidence now for development of
a south southwestward track. Dvorak analysis at 0430UTC based on shear pattern
with well-organized low level circulation just outside edge of deep convection
giving DT of 3.0. MET/PT 3.0 but CI held up at 3.5.

Freddy's convective structure remains moderately sheared, with good outflow to
the NW and development of banding in the western semicircle. The cyclone is
forecast continue to move to the west southwest during the next 48 hours under
the influence of a mid-level ridge to the southeast. Freddy is expected to
intensify at less than the normal rate due to persistent vertical wind shear.
After 24 or 36 hours, wind shear is forecast to decrease, but as the cyclone
moves over cooler sea surface temperatures, it is forecast to gradually weaken.


Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 08/1300 UTC by Darwin TCWC.
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Re: NW Australia: FREDDY - Tropical Cyclone : Discussion

#44 Postby Crostorm » Sun Feb 08, 2009 6:18 am

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#45 Postby Crostorm » Sun Feb 08, 2009 6:18 am

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 08 FEB 2009 Time : 103000 UTC
Lat : 16:23:14 S Lon : 108:33:00 E


CI# /Pressure/ Vmax
3.3 / 989.2mb/ 51.0kt


Final T# Adj T# Raw T#
(3hr avg)
3.2 3.2 3.2

Latitude bias adjustment to MSLP : +2.4mb

Center Temp : -66.4C Cloud Region Temp : -67.7C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : INDIAN
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : ON
Rapid Dissipation Flag : OFF
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#46 Postby HURAKAN » Sun Feb 08, 2009 9:38 am

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by DARWIN TROPICAL CYCLONE WARNING CENTRE
at: 1252 UTC 08/02/2009
Name: Tropical Cyclone Freddy
Data At: 1200 UTC
Latitude: 16.6S
Longitude: 108.5E
Location Accuracy: within 50 nm [95 km]
Movement Towards: west southwest [256 deg]
Speed of Movement: 10 knots [19 km/h]
Maximum 10-Minute Wind: 50 knots [95 km/h]
Maximum 3-Second Wind Gust: 70 knots [130 km/h]
Central Pressure: 987 hPa
Radius of 34-knot winds NE quadrant: 60 nm [110 km]
Radius of 34-knot winds SE quadrant: 60 nm [110 km]
Radius of 34-knot winds SW quadrant: 150 nm [280 km]
Radius of 34-knot winds NW quadrant: 150 nm [280 km]
Radius of 48-knot winds NE quadrant: 35 nm [65 km]
Radius of 48-knot winds SE quadrant: 35 nm [65 km]
Radius of 48-knot winds SW quadrant: 35 nm [65 km]
Radius of 48-knot winds NW quadrant: 35 nm [65 km]
Radius of 64-knot winds:
Radius of Maximum Winds: 30 nm [55 km]
Dvorak Intensity Code: T3.0/3.5/D0.5/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 250 nm [465 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 09/0000: 17.4S 106.6E: 075 [140]: 050 [095]: 987
+24: 09/1200: 18.3S 104.8E: 095 [175]: 045 [085]: 988
+36: 10/0000: 19.2S 102.6E: 120 [220]: 045 [085]: 988
+48: 10/1200: 20.2S 100.7E: 145 [270]: 040 [075]: 991
+60: 11/0000: 21.0S 98.8E: 175 [325]: 035 [065]: 993
+72: 11/1200: 21.8S 97.6E: 205 [380]: 035 [065]: 992
REMARKS:
Tropical Cyclone Freddy is located far to the northwest of the Western
Australian mainland.

Location is based on extrapolation of recent visible imagery fixes and
corroborated by 0930 UTC AMSUB and 1103 UTC SSMIS fixes [after navigation
correction]. System remains affected by vertical shear and may be starting to
experience the influence of cooler sea surface temperatures, so intensity has
not increased. Dvorak analysis based on shear pattern had centre just inside
the deep overcast, giving DT of 3.5, but MET/PT was assessed at 3.0, giving FT
3.0 and CI 3.5.

The cyclone is forecast continue to move to the west southwest during the next
48 hours under the influence of a mid-level ridge to the southeast. Wind shear
is forecast to decrease over the next 24 hours, but with the cyclone moving over
cooler sea surface temperatures, it is forecast to gradually weaken.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 08/1900 UTC by Darwin TCWC.
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#47 Postby HURAKAN » Sun Feb 08, 2009 10:12 am

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#48 Postby HURAKAN » Sun Feb 08, 2009 11:57 am

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Looking less organized.
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#49 Postby HURAKAN » Sun Feb 08, 2009 4:50 pm

Australian Government Bureau of Meteorology
Western Australia

TROPICAL CYCLONE INFORMATION BULLETIN
Issued at 3:37 am WDT on Monday 9 February 2009
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE DARWIN

Tropical Cyclone Freddy (Category 1) was located at 3 am WDT near 17.0S 107.6E,
that is 1060 km west northwest of Karratha and 880 km northwest of Exmouth and
moving west southwest at 20 kilometres per hour.
Tropical Cyclone Freddy is located far to the northwest of the WA coast. It is
likely to continue to move west southwestwards away from the WA mainland.
Gales are not expected to affect WA.
The next Information Bulletin will be issued at 10 am WDT.
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#50 Postby HURAKAN » Sun Feb 08, 2009 10:47 pm

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#51 Postby HURAKAN » Sun Feb 08, 2009 10:48 pm

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0115 UTC 09/02/2009
Name: Tropical Cyclone Freddy
Data At: 0000 UTC
Latitude: 17.5S
Longitude: 106.9E
Location Accuracy: within 20 nm [37 km]
Movement Towards: west southwest [240 deg]
Speed of Movement: 9 knots [16 km/h]
Maximum 10-Minute Wind: 40 knots [75 km/h]
Maximum 3-Second Wind Gust: 55 knots [100 km/h]
Central Pressure: 992 hPa
Radius of 34-knot winds NE quadrant: 40 nm [75 km]
Radius of 34-knot winds SE quadrant: 40 nm [75 km]
Radius of 34-knot winds SW quadrant: 120 nm [220 km]
Radius of 34-knot winds NW quadrant: 120 nm [220 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: 30 nm [55 km]
Dvorak Intensity Code: D2.5/3.0/W1.0/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 210 nm [390 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 09/1200: 18.5S 104.8E: 050 [095]: 035 [065]: 996
+24: 10/0000: 19.3S 102.6E: 080 [150]: 035 [065]: 995
+36: 10/1200: 20.2S 100.6E: 110 [210]: 030 [055]: 998
+48: 11/0000: 20.9S 98.9E: 145 [270]: 030 [055]: 997
+60: 11/1200: 21.6S 97.7E: 190 [355]: 025 [045]: 999
+72: 12/0000: 21.7S 96.2E: 240 [445]: 025 [045]: 1000
REMARKS:
Freddy has weakened over the last 24 hours although shear has not increased,
indicating cooler waters are already rendering Freddy more susceptible to shear.
Weakening is expected to continue as Freddy moves toward even cooler waters.

Location is based on early VIS imagery and extrapolation of microwave fixes at
1810 and 2207Z. Dvorak analysis based on shear pattern with centre <0.75 but
>0.5 degrees from overcast giving DT of 2.5, which matches MET. CI held at 3.0.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 09/0700 UTC by Perth TCWC.
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#52 Postby HURAKAN » Mon Feb 09, 2009 5:03 am

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0712 UTC 09/02/2009
Name: Tropical Cyclone Freddy
Data At: 0600 UTC
Latitude: 18.3S
Longitude: 105.8E
Location Accuracy: within 20 nm [37 km]
Movement Towards: west southwest [238 deg]
Speed of Movement: 11 knots [21 km/h]
Maximum 10-Minute Wind: 35 knots [65 km/h]
Maximum 3-Second Wind Gust: 50 knots [95 km/h]
Central Pressure: 996 hPa
Radius of 34-knot winds NE quadrant: 40 nm [75 km]
Radius of 34-knot winds SE quadrant: 40 nm [75 km]
Radius of 34-knot winds SW quadrant: 120 nm [220 km]
Radius of 34-knot winds NW quadrant: 120 nm [220 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: 30 nm [55 km]
Dvorak Intensity Code: T2.5/3.0/W0.5/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 130 nm [240 km]
Storm Depth: Medium
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 09/1800: 19.3S 103.7E: 050 [095]: 035 [065]: 995
+24: 10/0600: 20.1S 101.5E: 080 [150]: 030 [055]: 998
+36: 10/1800: 21.0S 99.6E: 115 [210]: 030 [055]: 997
+48: 11/0600: 21.7S 98.1E: 145 [270]: 025 [045]: 1000
+60: 11/1800: 22.1S 96.8E: 195 [355]: 025 [045]: 999
+72: 12/0600: 21.7S 95.1E: 240 [445]: 025 [045]: 1000
REMARKS:
Freddy has weakened over the last 24 hours although shear has not increased,
indicating cooler waters are already rendering Freddy more susceptible to shear.
Weakening is expected to continue as Freddy moves toward even cooler waters.
The ASCAT pass at 0240 indicated limited gales and gales may already be confined
to the south and southwest but a cautious approach will see high seas warnings
continued for a little while.

Location is based on VIS imagery Dvorak analysis based on shear pattern with
centre <0.75 but >0.5 degrees from overcast giving DT of 2.5, which matches MET.
CI held at 3.0, although with a 6-hour weakening rule [ref. Brown and Franklin]
it could be dropped to 2.5 as early as this issue.



Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 09/1300 UTC by Perth TCWC.
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#53 Postby HURAKAN » Mon Feb 09, 2009 8:47 am

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1300 UTC 09/02/2009
Name: Tropical Cyclone Freddy
Data At: 1200 UTC
Latitude: 18.8S
Longitude: 104.6E
Location Accuracy: within 25 nm [46 km]
Movement Towards: west southwest [242 deg]
Speed of Movement: 12 knots [22 km/h]
Maximum 10-Minute Wind: 35 knots [65 km/h]
Maximum 3-Second Wind Gust: 50 knots [95 km/h]
Central Pressure: 996 hPa
Radius of 34-knot winds NE quadrant: 40 nm [75 km]
Radius of 34-knot winds SE quadrant: 40 nm [75 km]
Radius of 34-knot winds SW quadrant: 100 nm [185 km]
Radius of 34-knot winds NW quadrant: 100 nm [185 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: 30 nm [55 km]
Dvorak Intensity Code: T2.5/3.0/W0.5/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 140 nm [260 km]
Storm Depth: Medium
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 10/0000: 19.6S 102.3E: 055 [100]: 035 [065]: 995
+24: 10/1200: 20.4S 100.5E: 085 [155]: 030 [055]: 998
+36: 11/0000: 20.8S 98.6E: 120 [220]: 030 [055]: 997
+48: 11/1200: 21.3S 97.2E: 150 [280]: 025 [045]: 1000
+60: 12/0000: 21.5S 95.8E: 200 [365]: 025 [045]: 1000
+72: 12/1200: 21.2S 93.8E: 245 [455]: 025 [045]: 1000
REMARKS:
Freddy is at marginal cyclone intensity over open waters well away from the
Australian mainland. Satellite imagery continues to show deep convection
constrained to the west of the centre consistent with ongoing moderate
[15-20knots] wind shear. The cyclone is now moving over cooler waters which
appears to be contributing to the weakening process.

Scatterometry [ASCAT and QSCAT] indicate the system is at marginal TC intensity.
Dvorak analysis: Shear pattern centre -0.5 from deep convection suggesting DT
2.5-3.0; MET/PT2.5 so FT=2.5 and CI held at 3.0.

Gradual weakening is expected as Freddy moves over waters less than 25C.
However, shear is not expected to increase and it is possible that should
convection be sustained overnight with the diurnal peak that gales may persist
particularly on the southwestern side for the next 12-15 hours. Continued steady
west southwest motion is expected.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 09/1900 UTC by Perth TCWC.
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#54 Postby HURAKAN » Mon Feb 09, 2009 6:20 pm

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TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1830 UTC 09/02/2009
Name: Tropical Cyclone Freddy
Data At: 1800 UTC
Latitude: 19.2S
Longitude: 103.5E
Location Accuracy: within 25 nm [46 km]
Movement Towards: west southwest [247 deg]
Speed of Movement: 11 knots [21 km/h]
Maximum 10-Minute Wind: 35 knots [65 km/h]
Maximum 3-Second Wind Gust: 50 knots [95 km/h]
Central Pressure: 996 hPa
Radius of 34-knot winds NE quadrant: 40 nm [75 km]
Radius of 34-knot winds SE quadrant: 50 nm [95 km]
Radius of 34-knot winds SW quadrant: 100 nm [185 km]
Radius of 34-knot winds NW quadrant: 90 nm [165 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: 30 nm [55 km]
Dvorak Intensity Code: T2.5/3.0/W0.5/24HRS
Pressure of outermost isobar: 1002 hPa
Radius of outermost closed isobar: 140 nm [260 km]
Storm Depth: Medium
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 10/0600: 19.9S 101.4E: 055 [100]: 030 [055]: 998
+24: 10/1800: 20.5S 99.4E: 085 [155]: 030 [055]: 998
+36: 11/0600: 21.1S 97.9E: 120 [220]: 025 [045]: 1000
+48: 11/1800: 21.4S 96.5E: 150 [280]: 025 [045]: 1000
+60: 12/0600: 21.2S 94.8E: 200 [365]: 025 [045]: 1000
+72: 12/1800: 21.1S 92.5E: 245 [455]: 025 [045]: 1001
REMARKS:
Freddy is at marginal cyclone intensity over open waters well away from the
Australian mainland. Satellite imagery continues to show deep convection
constrained to the west of the centre consistent with ongoing moderate
[15-20knots] wind shear. The cyclone is now moving over cooler waters which
appears to be contributing to the weakening process.

Gradual weakening is expected as Freddy moves over waters less than 25C. Shear
is not expected to increase and it is possible that gales may persist
particularly on the southwestern side for the next 6-12 hours. Continued steady
west southwest motion is expected.

Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 10/0100 UTC by Perth TCWC.
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Re: NW Australia: FREDDY - Tropical Cyclone : Discussion

#55 Postby HURAKAN » Mon Feb 09, 2009 8:13 pm

Image

WTXS32 PGTW 092100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE 14S (FREDDY) WARNING NR 008//
RMKS/
1. TROPICAL CYCLONE 14S (FREDDY) WARNING NR 008
02 ACTIVE TROPICAL CYCLONES IN SOUTH IO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
091800Z --- NEAR 19.3S 103.5E
MOVEMENT PAST SIX HOURS - 240 DEGREES AT 11 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: 19.3S 103.5E
---
FORECASTS:
12 HRS, VALID AT:
100600Z --- 20.2S 101.0E
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: 260 DEG/ 10 KTS
---
24 HRS, VALID AT:
101800Z --- 20.5S 98.8E
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
092100Z POSITION NEAR 19.5S 102.9E.
TROPICAL CYCLONE (TC) 14S (FREDDY), LOCATED APPROXIMATELY 615 NM
WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT
11 KNOTS OVER THE PAST SIX HOURS. ANIMATED WATER VAPOR IMAGERY
INDICATES THE SYSTEM HAS LOST A SIGNIFICANT AMOUNT OF CONVECTION
AROUND THE LOW LEVEL CIRCULATION CENTER WHICH HAS BECOME PARTIALLY
EXPOSED. CURRENT CENTRAL WIND SPEED IS BASED ON SATELLITE INTENSITY
ESTIMATES FROM PGTW AND KNES AND FROM A 091019Z QUIKSCAT PASS AND
POSITION IS BASED ON ANIMATED INFRARED IMAGERY AND A 091512Z AMSU
PASS. ENVIRONMENTAL ANALYSIS INDICATES THAT TC 14S REMAINS IN AN AREA
OF MODERATE VERTICAL WIND SHEAR AND COOLER SEA SURFACE TEMPERA-TURES.
THESE FACTORS ARE CONTRIBUTING TO THE GRADUAL DISSIPATION OF THE
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 091800Z IS 13 FEET. REFER TO TROPICAL CYCLONE 13S (GAEL) WARNINGS
(WTXS31 PGTW) FOR TWELVE-HOURLY UPDATES.
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#56 Postby HURAKAN » Tue Feb 10, 2009 9:09 am

TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1217 UTC 10/02/2009
Name: Ex-Tropical Cyclone Freddy
Data At: 1200 UTC
Latitude: 21.0S
Longitude: 99.8E
Location Accuracy: within 25 nm [46 km]
Movement Towards: west southwest [252 deg]
Speed of Movement: 13 knots [24 km/h]
Maximum 10-Minute Wind: 30 knots [55 km/h]
Maximum 3-Second Wind Gust: 45 knots [85 km/h]
Central Pressure: 998 hPa
Radius of 34-knot winds NE quadrant:
Radius of 34-knot winds SE quadrant: 70 nm [130 km]
Radius of 34-knot winds SW quadrant: 70 nm [130 km]
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: 30 nm [55 km]
Dvorak Intensity Code: T2.0/2.5W0.5/24HRS
Pressure of outermost isobar: 1004 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: 11/0000: 21.6S 97.7E: 055 [100]: 030 [055]: 1000
+24: 11/1200: 22.3S 96.4E: 085 [155]: 025 [045]: 1001
+36: 12/0000: 21.9S 95.0E: 120 [220]: 025 [045]: 1002
+48: 12/1200: 21.4S 92.8E: 150 [280]: 025 [045]: 1003
+60: 13/0000: 21.1S 90.0E: 200 [365]: 020 [035]: 1003
+72: 13/1200: 21.3S 87.3E: 245 [455]: 020 [035]: 1003
REMARKS:
Ex-Tropical Cyclone Freddy has weakened over ocean waters of 24C. While the low
level centre has been within 1/2 degree of convection owing to a decrease in
wind shear in the past 24 hours, satellite imagery shows a decline in the
convective vigour.

Dvorak analysis: FT=MET/PT=2.0 and CI at 2.5.

Thus circulation intensity estimated at 30 knots. However, marginal gales may
still be occurring in southern quadrants as a result of the steady west
southwest motion at 12-13 knots, so shipping warnings continue for the short
term.

Copyright Commonwealth of Australia
==
There will be no further bulletins for this system unless it reintensifies.
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Re: NW Australia: FREDDY - Tropical Cyclone : Discussion

#57 Postby Crostorm » Fri Feb 13, 2009 6:07 pm

Freddy Freddy :D

Image
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