NW Australia: Tropical Cyclone Ophelia

[Crostorm]

Oh yea

[G.B.]

65kts-974mb

[G.B.]

IDW27300
TROPICAL CYCLONE TECHNICAL SUMMARY: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1244 UTC 03/03/2008
Name: Ophelia
Data At: 1200 UTC
Latitude: 16.8S
Longitude: 116.5E
Location Accuracy: within 25 nm (46 km)
Movement Towards: west southwest (251 deg)
Speed of Movement: 8 knots (15 km/h)
Maximum 10-Minute Wind: 50 knots (95 km/h)
Maximum 3-Second Wind Gust: 70 knots (130 km/h)
Central Pressure: 980 hPa
Radius of 34-knot winds NE quadrant: 45 nm (85 km)
Radius of 34-knot winds SE quadrant: 60 nm (110 km)
Radius of 34-knot winds SW quadrant: 60 nm (110 km)
Radius of 34-knot winds NW quadrant: 50 nm (95 km)
Radius of 48-knot winds NE quadrant: 20 nm (37 km)
Radius of 48-knot winds SE quadrant: 20 nm (37 km)
Radius of 48-knot winds SW quadrant: 20 nm (37 km)
Radius of 48-knot winds NW quadrant: 20 nm (37 km)
Radius of 64-knot winds:
Radius of Maximum Winds: 10 nm (19 km)
Dvorak Intensity Code: T3.5/3.5/W0.5/24HRS
Pressure of outermost isobar: 1004 hPa
Radius of outermost closed isobar: 90 nm (165 km)
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
(UTC) : degrees : nm (km): knots(km/h): hPa
+12: 04/0000: 17.2S 114.8E: 050 (095): 055 (100): 972
+24: 04/1200: 17.8S 113.1E: 075 (140): 055 (100): 972
+36: 05/0000: 18.5S 111.2E: 095 (175): 050 (095): 980
+48: 05/1200: 19.4S 109.7E: 115 (215): 040 (075): 988
REMARKS:
Ophelia is a small system that has weakened under N/NE shear in the last 12 hours.

Dvorak analysis: FT of 3.5 based on shear pattern supported by PAT, with CI at 3.5.

Being such a small system, fluctuations in intensity are to be expected and some re-intensification is still possible overnight should the environmental shear drop even by a small degree as some models suggest.

After 00z 05 March, weakening seems likely with indications of increasing N/NW shear and
movement over cooler SSTs particularly as it moves west of 110E. Models maintain a consistent west to west southwest track for the next 48 hours, approximately parallel to the Pilbara coast under the influence of a persisting mid-level ridge to the south.

Notes:
This product is issued every six hours; the Cyclone Advices (Watches and Warnings) are
usually issued more frequently and contain more useful information for coastal communities.

Time Conversion from UTC to local:
WST add 8 hrs (Add another hour for daylight saving)
CST add 9 hrs 30 min
EST add 10 hrs (Add another hour for daylight saving)
==
The next bulletin for this system will be issued by: 03/1900 UTC by Perth TCWC.

[G.B.]

Position on NRL:

03/0300Z 17.1S 118.1E
03/1200Z 16.6S 116.6E

Shouldn't the direction be WNW rather than WSW?

[HURAKAN]

Convection continues to increase.

[Chacor]

Position on NRL:

03/0300Z 17.1S 118.1E
03/1200Z 16.6S 116.6E

Shouldn't the direction be WNW rather than WSW?

BoM's movement estimate is based on their centre estimates. NRL's are unofficial.

[G.B.]

Thanks for the clarification Chacor. To me satellite images look like Ophelia is going up and not down.

[HURAKAN]

Looking better.

[HURAKAN]

03/1430 UTC 16.4S 116.4E T3.0/3.0 OPHELIA -- South Indian Ocean

45 knot storm according to Dvorak.

[HURAKAN]

Australian Government Bureau of Meteorology
Western Australia

TROPICAL CYCLONE INFORMATION BULLETIN
Issued at 9:40 pm WDT on Monday, 3 March 2008
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

At 9 pm WDT Tropical Cyclone Ophelia [Category 2] was located near 16.8S 116.5E,
that is 440 km north of Karratha and 620 km north northeast of Exmouth moving
west southwest at 15 kilometres per hour.

Tropical Cyclone Ophelia continues to track to the west southwest and does not
pose a threat to coastal communities within the next 48 hours. Ophelia is
expected to continue moving approximately parallel to the coast and eventually
weaken during Wednesday and Thursday well out to sea.

The next Information Bulletin will be issued at 4 am WDT.

[HURAKAN]

Nicely looking.

[G.B.]

IDW27300
TROPICAL CYCLONE TECHNICAL SUMMARY: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0047 UTC 04/03/2008
Name: Ophelia
Data At: 0000 UTC
Latitude: 17.2S
Longitude: 114.6E
Location Accuracy: within 30 nm (55 km)
Movement Towards: west southwest (258 deg)
Speed of Movement: 9 knots (17 km/h)
Maximum 10-Minute Wind: 50 knots (95 km/h)
Maximum 3-Second Wind Gust: 70 knots (130 km/h)
Central Pressure: 982 hPa
Radius of 34-knot winds NE quadrant: 60 nm (110 km)
Radius of 34-knot winds SE quadrant: 80 nm (150 km)
Radius of 34-knot winds SW quadrant: 80 nm (150 km)
Radius of 34-knot winds NW quadrant: 65 nm (120 km)
Radius of 48-knot winds NE quadrant: 20 nm (37 km)
Radius of 48-knot winds SE quadrant: 20 nm (37 km)
Radius of 48-knot winds SW quadrant: 20 nm (37 km)
Radius of 48-knot winds NW quadrant: 20 nm (37 km)
Radius of 64-knot winds:
Radius of Maximum Winds: 10 nm (19 km)
Dvorak Intensity Code: T3.5/3.5/S0.0/12HRS
Pressure of outermost isobar: 1006 hPa
Radius of outermost closed isobar: 120 nm (220 km)
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
(UTC) : degrees : nm (km): knots(km/h): hPa
+12: 04/1200: 17.9S 112.8E: 050 (095): 055 (100): 974
+24: 05/0000: 18.8S 110.8E: 070 (130): 050 (095): 982
+36: 05/1200: 19.6S 109.2E: 085 (155): 045 (085): 986
+48: 06/0000: 20.4S 107.8E: 105 (195): 040 (075): 990
REMARKS:
Dvorak analysis: FT/CI of 3.5 based on curved band wrap of 0.8 supported by MET with CI at 3.5.
Being such a small system, Ophelia's intensity has been vulnerable to shear even though shear
estimates have been less than 15 knots. Convection has increased overnight and in recent
satellite images appears to be more organised. It is possible that some intensification is possible in the next 12/24 hours.
Thereafter weakening seems more likely with movement over cooler SST particularly as it moves west of 110E and south of 20S.
There is high confidence in the continuing steady W/SW track in the next 48 hours based on
strong agreement amongst the range of model guidance with a persisting mid-level ridge to the south.

Notes:
This product is issued every six hours; the Cyclone Advices (Watches and Warnings) are
usually issued more frequently and contain more useful information for coastal communities.

Time Conversion from UTC to local:
WST add 8 hrs (Add another hour for daylight saving)
CST add 9 hrs 30 min
EST add 10 hrs (Add another hour for daylight saving)
==
The next bulletin for this system will be issued by: 04/0700 UTC by Perth TCWC.

[G.B.]

[HURAKAN]

Looking great.

[HURAKAN]

04/0230 UTC 18.2S 113.8E T3.5/3.5 OPHELIA -- South Indian Ocean

Begins to re-intensify.

[G.B.]

IDW27300
TROPICAL CYCLONE TECHNICAL SUMMARY: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0656 UTC 04/03/2008
Name: Ophelia
Data At: 0600 UTC
Latitude: 17.2S
Longitude: 113.6E
Location Accuracy: within 30 nm (55 km)
Movement Towards: west (264 deg)
Speed of Movement: 10 knots (18 km/h)
Maximum 10-Minute Wind: 50 knots (95 km/h)
Maximum 3-Second Wind Gust: 70 knots (130 km/h)
Central Pressure: 982 hPa
Radius of 34-knot winds NE quadrant: 60 nm (110 km)
Radius of 34-knot winds SE quadrant: 100 nm (185 km)
Radius of 34-knot winds SW quadrant: 100 nm (185 km)
Radius of 34-knot winds NW quadrant: 40 nm (75 km)
Radius of 48-knot winds NE quadrant: 20 nm (37 km)
Radius of 48-knot winds SE quadrant: 20 nm (37 km)
Radius of 48-knot winds SW quadrant: 20 nm (37 km)
Radius of 48-knot winds NW quadrant: 20 nm (37 km)
Radius of 64-knot winds:
Radius of Maximum Winds: 10 nm (19 km)
Dvorak Intensity Code: T3.5/3.5/S/12HRS
Pressure of outermost isobar: 1006 hPa
Radius of outermost closed isobar: 120 nm (220 km)
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
(UTC) : degrees : nm (km): knots(km/h): hPa
+12: 04/1800: 18.0S 111.9E: 050 (095): 050 (095): 982
+24: 05/0600: 19.0S 110.0E: 070 (130): 050 (095): 982
+36: 05/1800: 19.8S 108.5E: 085 (155): 045 (085): 986
+48: 06/0600: 20.7S 107.2E: 095 (175): 035 (065): 992
REMARKS:
Dvorak analysis: FT/CI of 3.5 based on curved band wrap of 0.8 supported by MET with CI at 3.5.
Being such a small system, Ophelia's intensity has been vulnerable to shear even though shear
estimates remain less than 15 knots. Deep convection has persisted through the day though the low level centre remains slightly to the north of the mid level circulation.
Intensity is forecast to remain steady over 24 hours and thereafter weakening seems more likely with movement over cooler SST particularly as it moves west of 110E and south of 20S.
There is high confidence in the steady W/SW track in the next 48 hours based on
strong agreement amongst the range of model guidance with a persisting mid-level ridge to the south.

Notes:
This product is issued every six hours; the Cyclone Advices (Watches and Warnings) are
usually issued more frequently and contain more useful information for coastal communities.

Time Conversion from UTC to local:
WST add 8 hrs (Add another hour for daylight saving)
CST add 9 hrs 30 min
EST add 10 hrs (Add another hour for daylight saving)
==
The next bulletin for this system will be issued by: 04/1300 UTC by Perth TCWC.

[G.B.]

[G.B.]

[G.B.]

Convection has decreased

[G.B.]

IDW27300
TROPICAL CYCLONE TECHNICAL SUMMARY: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 1250 UTC 04/03/2008
Name: Ophelia
Data At: 1200 UTC
Latitude: 17.7S
Longitude: 112.8E
Location Accuracy: within 30 nm (55 km)
Movement Towards: west southwest (237 deg)
Speed of Movement: 9 knots (17 km/h)
Maximum 10-Minute Wind: 55 knots (100 km/h)
Maximum 3-Second Wind Gust: 80 knots (150 km/h)
Central Pressure: 974 hPa
Radius of 34-knot winds NE quadrant: 60 nm (110 km)
Radius of 34-knot winds SE quadrant: 100 nm (185 km)
Radius of 34-knot winds SW quadrant: 100 nm (185 km)
Radius of 34-knot winds NW quadrant: 60 nm (110 km)
Radius of 48-knot winds NE quadrant: 20 nm (37 km)
Radius of 48-knot winds SE quadrant: 20 nm (37 km)
Radius of 48-knot winds SW quadrant: 20 nm (37 km)
Radius of 48-knot winds NW quadrant: 20 nm (37 km)
Radius of 64-knot winds:
Radius of Maximum Winds: 10 nm (19 km)
Dvorak Intensity Code: T4.0/4.0/D0.5/24HRS
Pressure of outermost isobar: 1006 hPa
Radius of outermost closed isobar: 120 nm (220 km)
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
(UTC) : degrees : nm (km): knots(km/h): hPa
+12: 05/0000: 18.6S 111.1E: 050 (095): 055 (100): 974
+24: 05/1200: 19.8S 109.4E: 070 (130): 045 (085): 986
+36: 06/0000: 20.7S 107.9E: 090 (165): 040 (075): 990
+48: 06/1200: 21.9S 106.9E: 110 (205): 030 (055): 996
REMARKS:
Dvorak analysis: FT/CI of 4.0 based on embedded centre (MG/DG DT 4.0) averaged over 3 hours.

Ophelia has shown some signs of intensification over the last 6 hours as evident on visible and microwave imagery.

Being such a small system, Ophelia's intensity has been vulnerable to shear even though shear
estimates remain less than 15 knots.

Intensity is forecast to remain steady over the next 12 hours and thereafter weakening seems likely with movement over cooler SSTs particularly as it moves west of 110E and south of 20S.

There is high confidence in the steady southwest track in the next 48 hours based on strong agreement amongst the range of model guidance with a persisting mid-level ridge to the south and an approaching mid-level trough.

Notes:
This product is issued every six hours; the Cyclone Advices (Watches and Warnings) are
usually issued more frequently and contain more useful information for coastal communities.

Time Conversion from UTC to local:
WST add 8 hrs (Add another hour for daylight saving)
CST add 9 hrs 30 min
EST add 10 hrs (Add another hour for daylight saving)
==
The next bulletin for this system will be issued by: 04/1900 UTC by Perth TCWC.