Potential TC near Solomon Islands

[Nev]

Not going to bother with a separate thread at this stage, but something to watch...

'Tropical cyclone could form near Solomon Islands this week but poses no threat to Queensland, BoM says' - ABC

SW Pacific - MTSAT rb - Jul 29, 0332z.jpg

Edit: Thought this might be worthy of a thread after all.

[Manukau heads obs]

surprising that there is a second tropical low developing this winter

[Nev]

JTWC picked up on this system yesterday evening and this afternoon have upgraded its chances of becoming a TC in the next 24 hrs to medium. RSMC Nadi also picked up on it this afternoon, but only rate its chances in the next 48 hrs as low…

ABPW10 PGTW 300230
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS REISSUED/300230Z-300600ZJUL2015//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/291421ZJUL2015//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
…
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 5.5S
163.7E, IS NOW LOCATED NEAR 4.3S 166.2E, APPROXIMATELY 400 NM
NORTHEAST OF SOLOMON ISLANDS. ANIMATED MSI DEPICTS AN AREA OF DEEP
CONVECTION ASSOCIATED WITH AN ELONGATED LLCC. A RECENT (292006Z)
RSCAT PASS SHOWS GOOD CONSOLIDATED LLCC, WITH LIMITED CONVECTION,
AS CAN BE SEEN IN THE 292204Z METOP-A IMAGE. UPPER-LEVEL ANALYSIS
INDICATES STRONG DIFFLUENCE AND POLEWARD VENTING ASSOCIATED WITH A
DEEP SHORTWAVE TROUGH EAST OF AUSTRALIA. DYNAMICAL MODEL GUIDANCE
INDICATES THAT THIS SYSTEM WILL SLOWLY INTENSIFY AS IT TRACKS
SOUTHEASTWARD UNDER THE UPPER-LEVEL STR. 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.
(2) NO OTHER SUSPECT AREAS.
3. JUSTIFICATION FOR REISSUE: AREA IN PARA 2.B.(1) UPGRADED TO A
MEDIUM.//

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Jul 29/2330 UTC 2015 UTC.

TROPICAL DISTURBANCE CENTRE [1004HPA] ANALYSED NEAR 5.0S 167.0E AT
292100UTC. SLOW MOVING. POSITION POOR.

ORGANISATION HAS SLIGHLY IMPROVED IN THE LAST 24 HOURS. CONVECTION
REMAINS PERSISTENT AROUND LLCC. SYSTEM LIES TO THE NORTH OF AN UPPER
RIDGE IN A MODERATELY SHEARED ENVIRONMENT. SST IS AROUND 30 DEGREES
CELSIUS.

GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND GRADUALLY MOVE IT
WESTWARDS WITH SLIGHT INTENSIFICATION.

POTENTIAL FOR THE SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW.

[bjb]

Yes, been watching this development since Wed.

When living in Solomon Islands and Vanuatu we used to say the only months without cyclones were July and August.
Looks like there is a new norm, cyclones can form any time of year, they are just more frequent in the wet season.

Barry

[Nev]

Hey Barry, yeah it would certainly be another one for the record books if it did develop.

Although JTWC still expect this TD to slowly intensify, this evening they have downgraded its chances of becoming a TC within the next 24 hours to low…

ABPW10 PGTW 310600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS/310600ZJUL2015-010600ZAUG2015//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/310151ZJUL2015//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
…
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 4.6S 166.5E,
IS NOW LOCATED NEAR 6.7S 167.5E, APPROXIMATELY 659 NM NORTH OF PORT
VILA, VANUATU. ANIMATED MSI DEPICTS A DISORGANIZED AREA OF DEEP
CONVECTION ASSOCIATED WITH A BROAD LLCC. RECENT SCATTEROMETRY
DATA SHOWS AN EXPANSIVE CIRCULATION WITH WEAK CORE WINDS. UPPER-LEVEL
ANALYSIS INDICATES STRONG DIFFLUENCE AND POLEWARD VENTING ASSOCIATED
WITH A DEEP SHORTWAVE TROUGH EAST OF AUSTRALIA. DYNAMICAL MODEL
GUIDANCE INDICATES THAT THIS SYSTEM WILL SLOWLY INTENSIFY AS IT
TRACKS SOUTHEASTWARD UNDER THE UPPER LEVEL STR. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS DOWNGRADED TO LOW.

[Nev]

RSMC Nadi this morning have slightly upgraded this TD's chances of becoming a TC in the next 12 to 48 hours to 'low to medium'…

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Jul 31/2318 UTC 2015 UTC.

TROPICAL DISTURBANCE 01F CENTRE [1002HPA] ANALYSED NEAR 8.7S 168.5E
AT 312100UTC. SLOW MOVING. POSITION POOR.

ORGANISATION HAS SLIGHLY IMPROVED IN THE LAST 24 HOURS. DEEP
CONVECTION REMAINS PERSISTENT AROUND LLCC. SYSTEM LIES TO THE NORTH
OF AN UPPER DIFFLUENT RIDGE IN A MODERATE TO HIGH SHEARED
ENVIRONMENT. OUTFLOW GOOD TO THE SOUTH BUT RESTRICTED ELSEWHERE. SST
IS AROUND 29 DEGREES CELSIUS. TD01F IS BEING STEERED TO THE SOUTH BY
A NORTHERLY DEEP LAYER MEAN FLOW TO AN AREA OF INCREASING SHEAR.

GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND GRADUALLY MOVE IT
SOUTHWARDS WITH SLIGHT INTENSIFICATION.

POTENTIAL FOR THE SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW TO MODERATE.

[Nev]

Not surprisingly, JTWC have bumped this TD's chances of becoming a TC within the next 24 hrs back up to medium. Looks a little more organised overnight, despite moving into lower SST's of 28C…

ABPW10 PGTW 012030
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS REISSUED/012030Z-020600ZAUG2015//
…
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 10.1S 170.4E
IS NOW LOCATED NEAR 11.0S 171.5E, APPROXIMATELY 530 NM NORTHWEST OF
NADI, FIJI. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY
DEPICTS A DEVELOPING CENTRAL DENSE OVERCAST FEATURE OBSCURING THE
LOW LEVEL CIRCULATION CENTER WITH IMPROVED CONVECTIVE BANDING
WRAPPING IN FROM THE NORTH. A 011716Z SSMIS 89GHZ MICROWAVE PARTIAL
IMAGE SHOWS ELONGATED LOW REFLECTIVE BANDING WITH THE BULK OF
CONVECTION SHEARED TO THE SOUTHEAST. UPPER LEVEL ANALYSIS INDICATES
STRONG DIFFLUENCE ALOFT AND POLEWARD VENTING ASSOCIATED WITH A DEEP
SHORTWAVE TROUGH EAST OF AUSTRALIA. MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1005 MB. DUE TO THE IMPROVED CONSOLIDATION
SEEN IN THE EIR AND MICROWAVE IMAGERY, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.

[Nev]

JTWC has issued a Tropical Cyclone Formation Alert this evening…

WTPS21 PGTW 020830
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 10.4S 171.4E TO 13.2S 174.9E
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
020800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 11.2S
171.9E. THE SYSTEM IS MOVING SOUTH-SOUTHEASTWARD AT 04 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 11.3S
171.9E IS NOW LOCATED NEAR 11.2S 171.9E, APPROXIMATELY 505 NM
NORTHWEST OF NADI, FIJI. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
DEPICTS A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC)
WITH PERSISTENT DEEP CONVECTION OBSCURING MOST OF THE LLCC. A
020318Z SSMI 37 GHZ IMAGE REVEALS CURVED DEEP CONVECTIVE BANDING
WRAPPING INTO A SLOWLY CONSOLIDATING LLCC. A 011904Z RAPIDSCAT
IMAGE SHOWED EXTENSIVE GALE-FORCE WINDS OVER THE SOUTHERN SEMI-
CIRCLE OF THE SYSTEM, ENHANCED BY THE STRONG GRADIENT ASSOCIATED
WITH THE HIGH PRESSURE SYSTEM CENTERED NEAR NEW ZEALAND. RAPIDSCAT
CONTINUES TO SHOW WEAKER, 15 TO 25 KNOT WINDS, OVER THE NORTHERN
SEMI-CIRCLE. UPPER-LEVEL ANALYSIS INDICATES LOW TO MODERATE
VERTICAL WIND SHEAR OFFSET BY STRONG DIFFLUENCE ALOFT AND POLEWARD
VENTING ASSOCIATED WITH A DEEP UPPER-LEVEL TROUGH EAST OF
AUSTRALIA. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO
30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002
MB. 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
030830Z.//
NNNN

[Manukau heads obs]

is this a symptom of globally warmer than normal sea surface temperatures (which are getting warmer and wamer with global warming)?
(although sea surface temperatures in the area are currently normal)
so maybe its due to twinning or stronger westerlies across the equator

[Nev]

JTWC has declared this low as TC this morning. Note that that's based on 35 kt 1-minute-averages, which is roughly the equivalent of only about 31 kt 10-minute-averages…

WTPS31 PGTW 022100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 01P (ONE) WARNING NR 001//
REF/A/JOINT TYPHOON WRNCEN PEARL HARBOR HI/020821ZAUG2015//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. TROPICAL CYCLONE 01P (ONE) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
021800Z --- NEAR 11.3S 173.1E
MOVEMENT PAST SIX HOURS - 110 DEGREES AT 06 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
...
REMARKS:
022100Z POSITION NEAR 11.4S 173.2E.
TROPICAL CYCLONE (TC) 01P (ONE), LOCATED APPROXIMATELY 511 NM
NORTHWEST OF SUVA, FIJI, HAS TRACKED EAST-SOUTHEASTWARD AT 06
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR)
SATELLITE IMAGERY DEPICTS A PARTIALLY EXPOSED LOW LEVEL CIRCULATION
CENTER (LLCC) WITH AN AREA OF DEEP CONVECTION SHEARED TO THE SOUTH
DUE TO 20-25 KNOT VERTICAL WIND SHEAR (VWS). THE EIR LOOP SHOWS
CONVECTIVE BANDING BEGINNING TO DEVELOP ALONG THE EASTERN PERIPHERY.
A 021857Z SSMIS 91GHZ MICROWAVE IMAGE FURTHER SHOWS A PARTIALLY
EXPOSED LLCC WITH FRAGMENTED BANDING WRAPPING INTO THE SOUTHERN
PERIPHERY FROM THE EAST. THE BYU HIGH RESOLUTION IMAGE FROM A
021030Z ASCAT PASS SHOWS 35 KNOT WINDS WRAPPING AROUND THE WESTERN
PERIPHERY WITH STRONGER GRADIENT WINDS FURTHER SOUTHWEST. UPPER
LEVEL ANALYSIS SHOWS A STRONG POLEWARD OUTFLOW SUSTAINING THE
CURRENT CONVECTION; HOWEVER, THE VWS IS IMPINGING ON QUICKER
CONSOLIDATION. SEA SURFACE TEMPERATURES (SSTS) NEAR 28 CELSIUS ARE
FAVORABLE. THE CURRENT POSITION IS BASED ON THE PARTIALLY EXPOSED
LLCC WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS BASED ON THE
AFOREMENTIONED ASCAT PASS AND SUPPORTED BY A DVORAK INTENSITY
ESTIMATE OF T2.5 (35 KNOTS) FROM PGTW. TC 01P IS TRACKING SLOWLY
SOUTHEASTWARD UNDER THE STEERING INFLUENCE OF A LOW TO MID-LAYERED
SUB-TROPICAL RIDGE (STR) TO THE EAST. A SECOND STR TO THE WEST WILL
REORIENT SOUTH OF THE CYCLONE OVER THE NEXT 12 TO 24 HOURS CAUSING A
TURN TO THE SOUTHWEST. ENVIRONMENTAL CONDITIONS WILL REMAIN MOSTLY
UNCHANGED ALLOWING THE CYCLONE TO INTENSIFY SLIGHTLY REACHING A PEAK
OF 45 KNOTS. BEYOND TAU 36, TC 01P WILL ROUND THE STR AXIS AND
ACCELERATE POLEWARD INTO A HIGH VERTICAL WIND SHEAR ENVIRONMENT AND
RAPIDLY DECREASING SSTS. THIS WILL CAUSE TC 01P TO WEAKEN AND FULLY
DISSIPATE OVER WATER AT THE END OF THE FORECAST PERIOD. LIMITED
MODEL GUIDANCE IS IN AGREEMENT IN THE OVERALL TRACK SHAPE; HOWEVER,
THERE IS A LARGE SPREAD IN THE TIMING OF THE RECURVES. THIS SPREAD
LEADS TO LOW CONFIDENCE IN THE JTWC FORECAST. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 021800Z IS 12 FEET. NEXT WARNINGS AT 030900Z AND
032100Z. THIS WARNING SUPERSEDES AND CANCELS REF A, JOINT TYPHOON
WRNCEN PEARL HARBOR HI 020821ZAUG2015 TROPICAL CYCLONE FORMATION
ALERT (WTPS21 PGTW 020830).//
NNNN

[Nev]

RSMC Nadi completely at odds with JTWC and this morning have downgraded this system's TC chances from low-to-moderate to low within the next 24 to 48 hours. Guess it's unlikely to ever be named…

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Aug 02/2333 UTC 2015 UTC.

TROPICAL DEPRESSION 01F CENTRE [1002HPA] ANALYSED NEAR 12.4S 172.8E
AT 022100UTC. SLOW MOVING. POSITION POOR.

ORGANISATION REMAINS GOOD IN THE LAST 24 HOURS. DEEP CONVECTION
REMAINS PERSISTENT AROUND LLCC IN THE PAST 24 HOURS BUT HAS REDUCED
IN AERIAL EXTEND IN THE PAST 3 HOURS. SYSTEM LIES UNDER AN UPPER
RIDGE IN A MODERATE TO HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE
SOUTH BUT RESTRICTED ELSEWHERE. SST IS AROUND 28 DEGREES CELSIUS.

GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND GRADUALLY MOVE IT
SOUTHWARDS WITH SLIGHT INTENSIFICATION.

POTENTIAL FOR THE SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 TO 48 HOURS IS LOW.

[Nev]

JTWC still calling this a TC, despite today's significant weakening. RSMC Nadi on the other hand still rating its TC chances as low...

WTPS31 PGTW 030900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 01P (ONE) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 01P (ONE) WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
030600Z --- NEAR 10.9S 172.6E
MOVEMENT PAST SIX HOURS - 090 DEGREES AT 02 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
...
REMARKS:
030900Z POSITION NEAR 11.0S 172.6E.
TROPICAL CYCLONE (TC) 01P (ONE), LOCATED APPROXIMATELY 548 NM
NORTHWEST OF SUVA, FIJI, HAS TRACKED EASTWARD AT 02 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS
DECAYING DEEP CONVECTION OVER A PARTIALLY-EXPOSED, BROAD LOW-LEVEL
CIRCULATION CENTER (LLCC). THE CONVECTIVE STRUCTURE HAS WEAKENED
SIGNIFICANTLY AND A 022138Z ASCAT IMAGE SHOWS THAT THE CIRCULATION
HAS BROADENED AS WELL; HOWEVER, GALE FORCE WINDS HAVE PERSISTED OVER
THE SOUTHERN SEMI-CIRCLE. A 030734Z SSMIS IMAGE REVEALS A DEFINED
LLCC WITH SHALLOW BANDING WRAPPING INTO AN ELONGATED CENTER, WHICH
ALONG WITH MSI SUPPORTS THE CURRENT POSITION AND SLOW TRACK MOTION
WITH FAIR CONFIDENCE. UPPER-LEVEL ANALYSIS SHOWS MODERATE NORTHERLY
VERTICAL WIND SHEAR (VWS) OFFSET BY STRONG POLEWARD OUTFLOW;
HOWEVER, THE VWS APPEARS TO BE THE DOMINANT INFLUENCE ON THE SYSTEM
CURRENTLY. SEA SURFACE TEMPERATURES (SSTS) NEAR 28 CELSIUS ARE
FAVORABLE. BASED ON THE ASCAT DATA, THE INITIAL INTENSITY IS HELD AT
35 KNOTS FOR THE TIME BEING ALTHOUGH LATER DATA MAY SUPPORT A LOWER
INTENSITY. TC 01P IS TRACKING SLOWLY EASTWARD UNDER A COMPETING
STEERING INFLUENCE BUT IS EXPECTED TO TURN SOUTHWESTWARD BY TAU 12
AS THE LOW-LEVEL STR SHIFTS SOUTHEAST OF THE SYSTEM. BY TAU 48, THE
STR WILL SHIFT FURTHER EAST AS A TROUGH DEEPENS TO THE SOUTHWEST,
WHICH WILL CAUSE TC 01P TO ACCELERATE SOUTH-SOUTHEASTWARD.
ENVIRONMENTAL CONDITIONS WILL REMAIN MOSTLY UNCHANGED UNTIL AFTER
TAU 36 AT WHICH POINT THE SYSTEM WILL TRACK UNDER THE UPPER-LEVEL
TROUGH AND INTO STRONG WESTERLY FLOW, WHICH WILL SERVE TO RAPIDLY
WEAKEN THE SYSTEM. ADDITIONALLY, RAPIDLY DECREASING SSTS WILL LEAD
TO DISSIPATION BY TAU 72. LIMITED MODEL GUIDANCE IS IN AGREEMENT IN
THE OVERALL TRACK SHAPE; HOWEVER, THERE IS A LARGE SPREAD IN THE
TIMING OF THE RECURVES. THIS SPREAD LEADS TO LOW CONFIDENCE IN THE
JTWC FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 030600Z IS 12
FEET. NEXT WARNINGS AT 032100Z AND 040900Z.//
NNNN

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Aug 03/0933 UTC 2015 UTC.

TROPICAL DEPRESSION 01F CENTRE [1002HPA] ANALYSED NEAR 11.6S 173.3E
AT 030600UTC MOVING SOUTH-SOUTHEAST AT ABOUT 05 KNOTS. POSITION POOR.

ORGANISATION HAS DECREASED AND DEEP CONVECTION HAS DECAYED
SIGNIFICANTLY IN THE PAST 12 HOURS. SYSTEM LIES UNDER AN UPPER RIDGE
IN A MODERATE TO HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE SOUTH
BUT RESTRICTED ELSEWHERE. SST IS AROUND 28 DEGREES CELSIUS.

GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND GRADUALLY MOVE IT
SOUTHWARDS.

POTENTIAL FOR THE SYSTEM TO DEVELOP INTO A TROPICAL CYCLONE IN THE
NEXT 24 HOURS IS LOW.

NO OTHER SIGNIFICANT TROPICAL DISTURBANCE ANALYSED OR FORECAST IN THE
AREA. .

[Nev]

JTWC has issued its Final Warning for this system this morning…

JTWC has issued its Final Warning for this system this morning…

WTPS31 PGTW 032100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 01P (ONE) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 01P (ONE) WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
031800Z --- NEAR 10.7S 172.0E
MOVEMENT PAST SIX HOURS - 235 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
...
REMARKS:
032100Z POSITION NEAR 10.9S 172.0E.
TROPICAL CYCLONE (TC) 01P (ONE), LOCATED APPROXIMATELY 443 NM
NORTH-NORTHEAST OF PORT VILA, VANUATU, HAS TRACKED SOUTHWESTWARD AT
04 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY INDICATES THE CONVECTION HAS CONTINUED TO DISPERSE
AS IT BEGAN TO TRACK POLEWARD INTO INCREASING VERTICAL WIND SHEAR. TC
01P HAS WEAKENED TO BELOW JTWC WARNING CRITERIA AND IS NOT EXPECTED
TO RE-INTENSIFY. 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 031800Z IS 10 FEET.//