SEPac: Tropical Cyclone Arthur/08F/09P

[Chacor]

TROPICAL DEPRESSION 08F [1002 HPA] CENTRE WAS LOCATED NEAR 11.9S
176.4W AT 210730 UTC MOVING EAST SLOW MOVING. POSITIONS POOR BASED ON
MTSAT EIR IMAGERY WITH ANIMATION, PERIPHERAL SURFACE OBSERVATIONS.
LLCC DIFFICULT TO LOCATE. SYSTEM ORGAINISATION HAS IMPROVED.
CONVECTION POPPING NEAR LLCC. 08F IS IN A FAVOURABLE ENVIRONMENT,
JUST SOUTH OF UPPER [250 HPA] OUTLOW. SHEAR IS MINIMAL. OUTLOW GOOD
IN ALL QUARDRANTS. BAND WRAPS 0.2 ON LOG10 SPIRAL YIELDING DT=1.5 PT
AGREES. T NUMBER LIMITED TO CONTRAINTS THUS YIELDING
T1.5/1.5/D0.5/12HRS.
GLOBAL MODELS INDICATE DEVELOPMENT IN THE NEXT 24 HOURS WITH GRADUAL
EASTWARD MOVEMENT.

THE POTENTIAL FOR 08F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT
24 TO 48 HOURS IS MODERATE TO HIGH.

From JTWC:
F. T1.5/1.5/STT: D0.5/15HRS (21/1130Z)

[Aslkahuna]

JTWC had an alert on this one last I checked (about an hour ago).

Steve

[Chacor]

WTPS21 PGTW 212030
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT/212021ZJAN07//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 12.1S 176.4W TO 13.8S 172.1W
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 IM-
AGERY AT 211800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 12.3S 176.1W. THE SYSTEM IS MOVING SOUTHEASTWARD AT 04
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.1S
176.4W IS NOW LOCATED NEAR 12.3S 176.1W, APPROXIMATELY 335 NM WEST-
NORTHWEST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED ENHANCED INFRARED
AND MULTISPECTRAL SATELLITE IMAGERY REVEAL DEEP CONVECTION LOCATED
DIRECTLY OVER THE LOW-LEVEL CIRCULATION CENTER (LLCC), WITH STRONG
LOW LEVEL INFLOW FROM THE SOUTHEAST AND NORTHWEST WRAPPING INTO THE
SYSTEM. UPPER LEVEL ANALYSIS CONTINUES TO INDICATE A FAVORABLE
ENVIRONMENT FOR DEVELOPMENT, WITH THE DISTURBANCE LOCATED JUST TO
THE SOUTH OF THE 200 MB ANTICYCLONE AXIS. VERTICAL WIND SHEAR OVER
THE SYSTEM REMAINS LOW, AND THE ANTICYCLONE ALOFT IS PROVIDING RADIAL
OUTFLOW CHANNELS. MAXIMUM SUSTAINED WINDS ARE ESTIMATED AT 25 TO 30
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1000 MB.
DUE TO INCREASED, SYMMETRICAL DEEP CONVECTION OVER THE LLCC, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFCANT TROPICAL CYCLONE WITH-
IN THE NEXT 24 HOURS IS GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
222030Z.//

[HurricaneBill]

Next name on the list is Zita.

[HURAKAN]

Tropical Disturbance Advisory Number A1 issued from RSMC NADI
Jan 22/2047 UTC 2007 UTC.

Correction to Dvorak..MET..
Tropical Depression 08F [998hPa] centre was re-located near 12.4S
175.2W at 221800 UTC. Position poor based on HRES MTSAT imagery with
animation. Depression moving east about 03 knots. Maximum 10-minute
average winds estimated at 25 to 30 knots and may incerease to 35
knots within 60 miles of centre in the next 12 to 24 hours.

Organisation generally improved past 6 to 12 hours. Development
influenced by diurnal variations. Convection still getting organised
but in last 6 hours, increased spatially and tops cooling. Outflow
rather restricted but developing to south and north. Dvorak based on
wrap of 0.4 on log10 spiral yielding a DT=2.5. MET=2.5, PAT=2.5.
Final T based on DT, thus T2.5/2.5/D0.5/24hrs. 08F lies under minimal
shear. SST around 29 to 30C. 08F expected to be gradually steered
east-southeast under a west to northwest steering field. Global
models generally agree on an east southeast track and further
intensification.
Potential for TD 08F to develop into a tropical cyclone in the next
in the next 24 hours is high.

The next Tropical Disturbance Advisory on TD 08F will be issued
around 230200 UTC.

[P.K.]

Dvorak estimates are now as high as T3.0 for this. In this case this is the estimate from TCWC Brisbane.

Tropical Low WNW of Samoa

222300 UTC

12.0S 174.6W

Analysis based on: MTSAT EIR and VIS 2222330 UTC.

Latitude Detection Sum : 3

Longitude Detection Sum: 8

Rotation in Vis and dry IR intrusion places possible centre east of coldest
cloud but still under anvil cloud. Dvorak based on shear pattern.
T3.0/3.0/D1.0/24HRS

[HurricaneBill]

If this becomes a storm, its name will be "Arthur".

[Chacor]

WTPS21 PGTW 222030
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT 222021Z JAN 07//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 12.6S 175.6W TO 14.9S 168.8W
WITHIN THE NEXT 06 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 IM-
AGERY AT 221900Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 12.8S 175.2W. THE SYSTEM IS MOVING EAST-SOUTHEASTWARD AT 03
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.3S
176.1W IS NOW LOCATED NEAR 12.6S 175.6W, APPROXIMATELY 275 NM WEST-
NORTHWEST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS A LARGE AREA OF PERSISTENT DEEP CONVECT-
ION OVER THE LOW LEVEL CIRCULATION CENTER (LLCC). A 221627Z AMSU
IMAGE DEPICTS A WELL-DEFINED LLCC WITH WEAK BANDING DEVELOPING
OVER THE SOUTHERN SEMI-CIRCLE. UPPER LEVEL ANALYSIS CONTINUES TO
INDICATE A FAVORABLE ENVIRONMENT FOR FURTHER DEVELOPMENT WITH THE
DISTURBANCE LOCATED UNDER A DEVELOPING ANTICYCLONE WITH WEAK VERTICAL
WIND SHEAR. ADDITIONALLY STRONG NORTHWESTERLY FLOW ASSOCIATED WITH
A MIDLATITUDE TROUGH IS ENHANCING POLEWARD OUTFLOW. MAXIMUM SUST-
AINED WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1000 MB. BASED ON THE FAVORABLE
ENVIRONMENT, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS GOOD. THIS
SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED
BY 232030Z.//

[Chacor]

426
WWSO21 ABRF 231231
IDQ20015
Australian Government Bureau of Meteorology
Queensland
Tropical Cyclone Warning Centre

Tropical Low W of Samoa

2312000 UTC

13.4S 173.8W

Analysis based on: MTSAT EIR 231030 UTC and surface observations.

Latitude Detection Sum : 8

Longitude Detection Sum: 19

T2.0/2.5/S/24HRS

Dvorak Analysis: Centre fix poor. Cloud pattern remains loosely organised with
little evidence of strong low level circulation centre. DT based on shear
pattern.

Next bulletin available at 231700 UTC

[P.K.]

TD08 has been named TC Arthur at 1200 GMT today.

[Chacor]

WTPS11 NFFN 241200
Tropical Disturbance Advisory Number A8 issued from RSMC NADI
Jan 24/1424 UTC 2007 UTC.

TROPICAL CYCLONE ARTHUR 08F [995HPA] CENTRE WAS LOCATED NEAR 14.7S
165.6W AT 241200 UTC. POSITION POOR BASED ON HRES MTSAT EIR IMAGERY
WITH ANIMATION AND PERIPHERAL SURFACE OBSERVATIONS. CYCLONE MOVING
EAST-SOUTHEAST ABOUT 21 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS
ESTIMATED AT 35 TO 40 KNOTS CLOSE THE CENTRE INCREASING TO 45 KNOTS
IN THE NEXT 12 HOURS. EXPECT WINDS OVER 33 KNOTS WITHIN 120 MILES OF
CENTRE IN THE NORTHEASTERN SEMICIRCLE AND WITHIN 90 MILES IN THE
SOUTHWESTERN SEMICIRCLE.

ORGANISATION SIGNIFICANTLY INCREASED IN THE PAST 3-4 HOURS WITH CDO
DEVELOPING OVER LLCC AND COLD CONVECTIVE BAND WRAPPING INTO THE
CENTRE. OUTFLOW POOR IN NORTHERN QUADRANT BUT GOOD ELSEWHERE. CYCLONE
LIES UNDER CVA REGION WITH DIVERGENCE ALOFT. CYCLONE CURRENTLY LIES
IN LOW SHEAR AREA BUT WILL ENCOUNTER INCREASING SHEAR AS IT MOVES
FURTHER SOUTH. DVORAK BASED ON WRAP OF 0.9 ON LOG10 SPIRAL YIELDING A
DT=3.5 MET=3.0 PAT=3.5. THUS, T3.0/3.0/D1.5/24HRS. SST AROUND 29 TO
30C. SYSTEM EXPECTED TO ACCELERATE EAST-SOUTHEAST UNDER A WESTERLY
STEERING FIELD. GLOBAL MODELS GENERALLY AGREE ON AN EAST SOUTHEAST
TRACK AND SOME INTENSIFICATION.

FORECAST:
12HRS VALID AT 250000 UTC NEAR 15.2S 163.3W MOV ESE 12KT WITH 45KT
CLOSE TO CENTRE. 24HRS VALID AT 251200 UTC NEAR 15.8S 160.9W MOV ESE
12KT WITH 50KT CLOSE TO CENTRE.

OUTLOOK:
36HRS VALID AT 260000 UTC NEAR 16.7S 159.0W MOV ESE 10KT WITH 50KT
CLOSE TO CENTRE.
48HRS VALID AT 261200 UTC NEAR 17.4S 157.7W MOV ESE 07KT WITH 40KT
CLOSE TO CENTRE.


THE NEXT TROPICAL DISTURBANCE ADVISORY ON TD 08F WILL BE ISSUED
AROUND 242000 UTC.

[Chacor]

WTPS11 NFFN 250000
Tropical Disturbance Advisory Number A10 issued from RSMC NADI
Jan 25/0202 UTC 2007 UTC.

TROPICAL CYCLONE ARTHUR 08F [975HPA] CENTRE WAS LOCATED NEAR 15.7S
160.8W AT 250000 UTC. POSITION FAIR BASED ON HRES MTSAT/GOES-11
EIR/VIS IMAGERY WITH ANIMATION. CYCLONE MOVING EAST-SOUTHEAST ABOUT
22 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS ESTIMATED AT 60 KNOTS CLOSE
THE CENTRE INCREASING TO 65 KNOTS IN THE NEXT 12 TO 24 HOURS. EXPECT
WINDS OVER 47 KNOTS WITHIN 30 MILES OF CENTRE AND OVER 33 KNOTS
WITHIN 150 MILES OF CENTRE IN THE SOUTHEASTERN SEMICIRCLE AND WITHIN
100 MILES OF CENTRE IN THE NORTHWESTERN SEMICIRCLE.

ORGANISATION STEADILY INCREASING. BANDING EYE FORMING AND HAS BEEN
CONTRACTING PAST 6 HOURS. COLD CONVECTIVE BANDS WRAPPING TIGHTLY INTO
THE CENTRE. OUTFLOW DEVELOPING STEADILY IN ALL QUADRANTS. CYCLONE
CURRENTLY LIES UNDER CVA REGION WITH STRONG DIVERGENCE AND MINIMAL
SHEAR. HOWEVER ARTHUR ACCELERATING INTO STRONGER SHEAR ZONE AND INTO
REGION PREVIOUSLY TRAVERSED BY TC ZITA. DVORAK BASED ON WRAP OF 1.0
ON LOG10 SPIRAL YIELDING A DT=3.5. 0.5 FOR BANDING YIELDS DT4.0.
MET=3.0 PAT=4.0. THUS, T4.0/4.0/D2.0/24HRS. SYSTEM EXPECTED TO TRACK
FURTHER EAST-SOUTHEAST UNDER A WESTERLY STEERING FIELD BEFORE TURNING
SOUTHEAST GRADUALLY. GLOBAL MODELS GENERALLY AGREE ON AN EAST
SOUTHEAST TRACK AND SOME FURTHER INTENSIFICATION.

FORECAST:
12HRS VALID AT 251200 UTC NEAR 17.3S 156.6W MOV ESE 22KT WITH 65KT
CLOSE TO CENTRE. 24HRS VALID AT 260000 UTC NEAR 20.1S 153.1W MOV ESE
22KT WITH 65KT CLOSE TO CENTRE.

OUTLOOK:
36HRS VALID AT 261200 UTC NEAR 24.0S 150.9W MOV ESE 21KT WITH 60KT
CLOSE TO CENTRE.
48HRS VALID AT 270000 UTC NEAR 28.0S 149.0W MOV ESE 21KT WITH 55KT
CLOSE TO CENTRE.

THE NEXT TROPICAL DISTURBANCE ADVISORY ON TD 08F WILL BE ISSUED
AROUND 250800 UTC.

[HurricaneBill]

NRL has it at 65KT (1-min).

[HURAKAN]

Tropical Disturbance Advisory Number A11 issued from RSMC NADI
Jan 25/0734 UTC 2007 UTC.

TROPICAL CYCLONE ARTHUR 08F [975HPA] CENTRE WAS LOCATED NEAR 16.2S
159.5W AT 250600 UTC. POSITION POOR BASED ON HRES MTSAT/GOES-11
EIR/VIS IMAGERY WITH ANIMATION. CYCLONE MOVING EAST-SOUTHEAST ABOUT
14 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS ESTIMATED AT 60 KNOTS CLOSE
THE CENTRE. EXPECT WINDS OVER 47 KNOTS WITHIN 50 MILES OF CENTRE AND
OVER 33 KNOTS WITHIN 150 MILES OF CENTRE IN THE SOUTHEASTERN
SEMICIRCLE AND WITHIN 100 MILES OF CENTRE IN THE NORTHWESTERN
SEMICIRCLE.

ORGANISATION HAS STEADIED AND SLOWED OVER THE PAST 3-4 HOURS. ARTHUR
UNDERGOING SOME SHEARING WITH LLCC LOCATED ON THE NORTHWESTERN EDGE
OF DEEP CONVECTION. OUTFLOW FAIR TO GOOD IN ALL QUADRANTS. CYCLONE
CURRENTLY LIES UNDER A BROAD WESTERLY FLOW WHICH WILL STEER IT TO THE
SOUTHEAST. ARTHUR WILL ENCOUNTER INCREASING SHEAR AS IT MOVES FURTHER
SOUTHEAST. DVORAK BASED ON SHEAR YIELDING DT=3.5. MET=3.0 PAT=3.5.
THUS, T3.5/4.0/D1.0/24HRS. SYSTEM EXPECTED TO TRACK FURTHER
EAST-SOUTHEAST UNDER A WESTERLY STEERING FIELD BEFORE TURNING
SOUTHEAST GRADUALLY. GLOBAL MODELS GENERALLY AGREE ON AN EAST
SOUTHEAST TRACK AND SOME FURTHER INTENSIFICATION.

FORECAST:
12HRS VALID AT 251800 UTC NEAR 18.6S 156.3W MOV SE 20KT WITH 50KT
CLOSE TO CENTRE. 24HRS VALID AT 260600 UTC NEAR 20.9S 153.6W MOV SE
17KT WITH 40KT CLOSE TO CENTRE.

OUTLOOK:
36HRS VALID AT 261800 UTC NEAR 23.8S 151.6W MOV SSE 17KT WITH 30KT
CLOSE TO CENTRE.
48HRS VALID AT 270600 UTC NEAR 27.3S 149.2W MOV SSE 20KT WITH 25KT
CLOSE TO CENTRE.

THE NEXT TROPICAL DISTURBANCE ADVISORY ON TC ARTHUR WILL BE ISSUED
AROUND 251400 UTC.


Arthur has not much time left to live.

[Chacor]

AFWA has issued its final satfix.

[P.K.]

Arthur is not quite done yet, up to 45kts from 40kts. Down from 990 to 987hPa. The convection does look over the centre now when it wasn't a bit earlier.

GALE WARNING 062 ISSUED FROM RSMC NADI Jan 26/0109 UTC 2007 UTC.

Tropical Cyclone ARTHUR [987hPa] centre was located near 19.7 South
153.9 West at 260000 UTC.
Position poor.
Repeat position 19.7S 153.9W at 260000 UTC.
Cyclone is moving southeast about 20 knots.
Expect sustained winds of 45 knots close to the centre decreasing to
35 knots in the next 12 to 24 hours.
Expect winds over 33 knots within 120 miles of centre in the
southeastern semicircle and within
90 miles of centre in the northwestern semicircle.

Forecast position near 23.1S 151.5W at 261200 UTC
and near 26.8S 149.7W at 270000 UTC.

All vessels within 300 nautical miles of the centre are requested to
send reports every three hours to RSMC NADI. VOS reporting ships use
normal channels. Other vessels fax plus 679 6720190 or email naditcc
at met dot gov dot fj.

This warning cancels and replaces warning 061.

[Chacor]

50kt now.

[P.K.]

Should cross to TCWC Wellington's AOR soon.

STORM WARNING 065 ISSUED FROM RSMC NADI Jan 26/1904 UTC 2007 UTC.

Tropical Cyclone ARTHUR [985hPa] centre was located near 24.5 South
149.7 West at 261800 UTC.
Position poor.
Repeat position 24.5S 149.7W at 261800 UTC.
Cyclone is moving southeast about 20 knots.
Expect sustained winds of 50 knots close to the centre decreasing to
40 knots in the next 12 hours.
Expect winds over 47 knots within 20 miles of centre and
over 33 knots within 120 miles of centre in the
southeastern semicircle and within
90 miles of centre in the northwestern semicircle.

Forecast position near 28.0S 147.4W at 270600 UTC
and near 31.7S 145.0W at 271800 UTC.

All vessels within 300 nautical miles of the centre are requested to
send reports every three hours to RSMC NADI. VOS reporting ships use
normal channels. Other vessels fax plus 679 6720190 or email naditcc
at met dot gov dot fj.

This warning cancels and replaces warning 064.

[Matt-hurricanewatcher]

This is a southeast Pacific storm,,.So yes the southeast Pacific can have storms.

[Coredesat]

This is old, but here's the first TCWC Wellington advisory:

Tropical Cyclone ARTHUR [980hPa]centre was located near 26.1 South
148.5 West at 262300 UTC.
Position fair.

Repeat position 26.1S 148.5W at 262300 UTC.

Cyclone is moving southeast about 20 knots.

Expect sustained winds of 55 knots close to the centre decreasing to
40 knots in the next 12 hours.

Expect winds over 47 knots within 30 miles of centre and
over 33 knots within 120 miles of centre in the
southeastern semicircle and within 90 miles of centre in the
northwestern semicircle.

Forecast position near 29.0S 146.0W at 271200 UTC
and near 33.0S 143.0W at 280000 UTC.

This warning cancels and replaces warning 262.

The JTWC revived Arthur for ONE advisory, saying it had restrengthened to 55 kt, but is still dissipating.