WPAC: Ex-Tropical Storm MERANTI (1010/11W)

[supercane]

12Z JMA analysis:
TROPICAL DEPRESSION 1004 HPA AT 22N 122E WEST 10 KT.

JTWC issued an updated significant tropical weather advisory to upgrade development chance to fair:
ABPW10 PGTW 071400
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS REISSUED/071400Z-080600ZSEP2010//
REF/A/MSG/NAVMARFCSTCEN PEARL HARBOR HI/071353ZSEP2010//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 071200Z, TROPICAL STORM 10W (MALOU) WAS LOCATED NEAR
35.4N 131.9E, APPROXIMATELY 190 NM WEST OF KYOTO, JAPAN, AND HAD
TRACKED EAST-NORTHEASTWARD AT 16 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 35 KNOTS GUSTING
TO 45 KNOTS. SEE REF A (WTPN33 PGTW 071500) FOR THE FINAL WARNING ON
THIS SYSTEM.
(2) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 24.6N
124.4E, IS NOW LOCATED NEAR 22.0N 122.5E, APPROXIMATELY 130 NM EAST-
SOUTHEAST OF KAOHSIUNG, TAIWAN. ANIMATED INFRARED SATELLITE IMAGERY
DEPICTS A PARTIALLY-EXPOSED, WELL-DEFINED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH AN AREA OF DEEP CONVECTION PERSISTING OVER THE
SOUTHWEST QUADRANT. A 071009Z SSMIS IMAGE AND TAIWAN RADAR DATA
INDICATE CURVED CONVECTIVE BANDING WRAPPING WEAKLY FROM THE SOUTHERN
TIP OF TAIWAN INTO THE SOUTHWEST QUADRANT. UPPER-LEVEL ANALYSIS
INDICATES AN UNFAVORABLE ENVIRONMENT WITH MODERATE, NORTHERLY
VERTICAL WIND SHEAR ASSOCIATED WITH AN ENCROACHING TUTT CELL.
ANIMATED WATER VAPOR IMAGERY, HOWEVER, INDICATES THAT THE TUTT CELL
HAS WEAKENED AND BECOME BROADER IN THE PAST 06 HOURS. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. BASED ON THE WELL-
DEFINED LLCC AND FORMATIVE BANDING, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO FAIR.
(2) NO OTHER SUSPECT AREAS.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
3. JUSTIFICATION FOR REISSUE: UPDATED PARA. 1.A.(1) TO REFLECT FINAL
WARNING FOR TS 10W AND UPGRADED AREA IN PARA. 1.B.(1) TO FAIR.//
NNNN



Increasing T numbers:
TXPN26 KNES 071538
SIMWIR
A. TROPICAL DISTURBANCE (90W)
B. 07/1501Z
C. 22.1N
D. 121.9E
E. THREE/MTSAT
F. T2.0/2.0/D1.5/24HRS
G. IR/EIR/SWIR/SSMIS/TMI
H. REMARKS...CENTER IS LOCATED LESS THAN 3/4 DEGREE FROM NEARBY STRONGEST
GRADIENT IN TEMPERATURE RESULTING IN A DT OF 2.5. MET IS 1.0 WHILE PT
IS 1.5. FT BASED ON CONSTRAINTS.
I. ADDL POSITIONS
07/1152Z 22.4N 122.7E SSMIS
07/1208Z 22.3N 122.2E TMI
...TURK
=

Center still exposed on microwave:

[supercane]

JMA 18Z analysis:
WARNING.
TROPICAL DEPRESSION 1004 HPA
AT 21.8N 121.5E SEA SOUTH OF OKINAWA MOVING WESTSOUTHWEST 10 KNOTS.
POSITION FAIR.
MAX WINDS 30 KNOTS NEAR CENTER.

WTPN21 PGTW 072000
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
140 NM EITHER SIDE OF A LINE FROM 22.0N 122.2E TO 21.8N 118.0E
WITHIN THE NEXT 06 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME. METSAT
IMAGERY, SYNOPTIC DATA AND RADAR DATA AT 071900Z INDICATE THAT A
CIRCULATION CENTER IS LOCATED NEAR 21.8N 121.7E. THE SYSTEM IS
MOVING WEST-SOUTHWESTWARD AT 08 KNOTS. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 17 TO 22 KNOTS AND MINIMUM SEA LEVEL PRESSURE
IS ESTIMATED TO BE NEAR 1004 MB. THIS IS SUPPORTED BY NEARBY SHIP AND
SURFACE OBSERVATIONS.
2. REMARKS: THE PERSISTENT AREA OF CONVECTION DESCRIBED IN PARA 1 IS
NOW LOCATED APPROXIMATELY 105 NM EAST-SOUTHEAST OF KAOHSIUNG, TAIWAN.
ANIMATED INFRARED SATELLITE IMAGERY DEPICTS A PARTIALLY-EXPOSED,
WELL-DEFINED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH AN AREA OF DEEP
CONVECTION PERSISTING OVER THE SOUTHWEST QUADRANT. ADDITIONALLY,
FORMATIVE BANDING HAS BEGUN TO WRAP TIGHTER INTO THE LLCC.
UPPER-LEVEL ANALYSIS INDICATES A TROPICAL UPPER TROPOSPHERIC TROUGH
(TUTT) CELL TO THE EAST IS HINDERING OUTFLOW TO THE NORTHEAST
QUADRANT OF THE SYSTEM. HOWEVER, WATER VAPOR SATELLITE ANIMATION
SHOWS GOOD EQUATORWARD OUTFLOW AND THE TUTT CELL WEAKENING AS IT
MOVES RAPIDLY WESTWARD. THE DISTURBANCE IS CURRENTLY EXPOSED TO
MODERATE-HIGH VERTICAL WIND SHEAR (VWS) BUT IS FORECAST TO MOVE INTO
AN AREA WITH LOWER VWS. THE SYSTEM IS BEING STEERED BY A MID-LEVEL
SUBTROPICAL RIDGE ANCHORED SOUTH OF JAPAN AND AVAILABLE NUMERIC
GUIDANCE FORECAST IT TO MOVE GENERALLY WEST TO NORTHWESTWARD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELED BY
082000Z.//
NNNN




TXPN26 KNES 072106
SIMWIR
A. TROPICAL DISTURBANCE (90W)
B. 07/2032Z
C. 21.5N
D. 121.2E
E. THREE/MTSAT
F. T2.0/2.0/D1.0/24HRS
G. IR/EIR/SWIR/AMSRE
H. REMARKS...DT=3.0 BASED ON SHEAR PATTERN WITH LOW LEVEL CENTER ON
EDGE OF OVERCAST. PT=2.0. MET=2.0. FT BASED ON MET.
I. ADDL POSITIONS
07/1755Z 21.5N 121.3E AMSRE
...SCHWARTZ
=

[Typhoon10]

HKO has this moving into SCS, maybe just becoming a TD, then heading back towards Taiwan

[StormingB81]

NRL took it off the site.

[Chacor]

Probably means JTWC is upgrading it.

[StormingB81]

Your right. It is back on there with a map like a TCFA However I tried to get it off JTWC however it says the site is not available so I cannot confirm it.

[StormingB81]

Here it is:

SUBJ/TROPICAL CYCLONE FORMATION ALERT//
WTPN21 PGTW 072000
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
140 NM EITHER SIDE OF A LINE FROM 22.0N 122.2E TO 21.8N 118.0E
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 17 TO 22 KNOTS. METSAT IM-
AGERY, SYNOPTIC DATA AND RADAR DATA AT 071900Z INDICATE THAT A
CIRCULATION CENTER IS LOCATED NEAR 21.8N 121.7E. THE SYSTEM IS
MOVING WEST-SOUTHWESTWARD AT 08 KNOTS.
2. REMARKS:
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 082000Z.

[supercane]

Already posted the TCFA above earlier in the day. Here's the first advisory on TD 11W.

WTPN31 PGTW 080300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL DEPRESSION 11W (ELEVEN) WARNING NR 001
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
080000Z --- NEAR 21.3N 120.6E
MOVEMENT PAST SIX HOURS - 245 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE, RADAR AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 21.3N 120.6E
---
FORECASTS:
12 HRS, VALID AT:
081200Z --- 21.5N 119.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 305 DEG/ 06 KTS
---
24 HRS, VALID AT:
090000Z --- 22.2N 118.6E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 320 DEG/ 09 KTS
---
36 HRS, VALID AT:
091200Z --- 23.6N 117.4E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
VECTOR TO 48 HR POSIT: 320 DEG/ 11 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
100000Z --- 25.3N 115.9E
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
080300Z POSITION NEAR 21.4N 120.3E.
THIS WARNING SUPERSEDES AND CANCELS REF A, NAVMARFCSTCEN 071951Z
SEP 10 TROPICAL CYCLONE FORMATION ALERT (WTPN21 PGTW 072000 )
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 080000Z IS 9 FEET.
NEXT WARNINGS AT 080900Z, 081500Z, 082100Z AND 090300Z.
REFER TO TROPICAL DEPRESSION 10W (MALOU) WARNINGS (WTPN33 PGTW)
FOR SIX-HOURLY UPDATES.
//

[supercane]

[Typhoon10]

HKO now have it, but track moving WSW then moving NNW just after passing south of Taiwan.

http://www.hko.gov.hk/wxinfo/currwx/tc_pos_1015.htm

[theavocado]

Your right. It is back on there with a map like a TCFA However I tried to get it off JTWC however it says the site is not available so I cannot confirm it.

Clearly the USNO site is not set up for all the traffic the western Pacific season generates.

As a workaround, someone I work with noticed that there is an RSS feed that supplies the information to the USNO site and it seems to be up when the site is down:

http://www.usno.navy.mil/NOOC/nmfc-ph/R ... wc-rss.php

[supercane]

WDPN31 PGTW 080300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 11W WARNING NR 01//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
A. TROPICAL DEPRESSION (TD) 11W (ELEVEN), LOCATED APPROXIMATELY
80 NM SOUTH-SOUTHEAST OF KAOHSIUNG, TAIWAN, HAS TRACKED WEST-
SOUTHWESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED
SATELLITE IMAGERY SHOWS THE WELL-DEFINED LOW-LEVEL CIRCULATION CENTER
(LLCC) HAS MOVED UNDER THE AREA OF DEEP CONVECTION TO THE SOUTHWEST.
ADDITIONALLY, FORMATIVE BANDING HAS RAPIDLY CONSOLIDATED AND WRAPPED
TIGHTER INTO THE LLCC. THE INITIAL POSITION IS BASED ON A RADAR
REFLECTIVITY LOOP FROM TAIWAN WITH HIGH CONFIDENCE. THE CURRENT
INTENSITY IS BASED ON DVORAK ESTIMATES FROM KNES AND PGTW AND FROM A
SHIP OBSERVATION LESS THAN 60 NM TO THE SOUTHEAST REPORTING 30-KNOT
WINDS AND 1001 MB SEA LEVEL PRESSURE. WATER VAPOR SATELLITE ANIMATION
SHOWS GOOD EQUATORWARD OUTFLOW AND 11W MOVING AWAY FROM THE TROPICAL
UPPER TROPOSPHERIC (TUTT) CELL TO THE NORTHEAST THAT WAS EARLIER
HINDERING POLEWARD OUTFLOW AND CAUSING HIGH VERTICAL WIND SHEAR
(VWS). THE SYSTEM IS BEING STEERED BY A LOW- TO MID-LEVEL SUBTROPICAL
RIDGE ANCHORED SOUTH OF JAPAN.
3. FORECAST REASONING.
A. THIS IS THE FIRST PROGNOSTIC REASONING FOR THIS SYSTEM.
B. AS TD 11W MOVES AWAY FROM THE TUTT CELL, VWS IS EXPECTED TO
DECREASE, ALLOWING THE SYSTEM TO GRADUALLY INTENSIFY. AFTER TAU 24,
THE SYSTEM WILL TRACK ON A MORE NORTHWEST TRAJECTORY ALONG THE
SOUTHWEST PERIPHERY OF THE AFOREMENTIONED STEERING RIDGE. TD 11W IS
EXPECTED TO MAKE LANDFALL NEAR SHANTOU, CHINA, AND DISSIPATE OVER
LAND BY TAU 48. THE INITIAL NUMERIC GUIDANCE IS VERY LIMITED AND
SPREAD OUT SIGNIFICANTLY OVER TIME. GFS IS TO THE RIGHT OF THE MODEL
ENVELOPE AND FAVORS AN ABRUPT POLEWARD MOTION. UKMET IS TO THE LEFT
AND PREDICTS A FLATTER, MORE WESTWARD DIRECTION. THIS TRACK FORECAST
IS TO THE LEFT OF CONSENSUS AND ACCOUNTS FOR A DEVELOPING CYCLONE
STEERED AT A HIGHER LEVEL AND WITH THE AID OF UPPER AIR OBSERVATIONS
FROM HONG KONG AND SHANTOU.//


TXPN26 KNES 080350
SIMWIR
A. 11W (NONAME)
B. 08/0232Z
C. 21.0N
D. 120.4E
E. THREE/MTSAT
F. T2.0/2.0/D0.5/24HRS
G. IR/EIR/VIS/SSMIS
H. REMARKS...BANDING MEASURES 5/10 FOR DT OF 2.5. MET IS 2.5. PT IS
2.0. FT BASED ON PT/CONSTRAINTS.
I. ADDL POSITIONS
07/2241Z 21.3N 121.2E SSMIS
08/0024Z 21.3N 120.9E SSMIS
...MS
=

[supercane]

00Z JMA analysis:
WARNING.
TROPICAL DEPRESSION 1004 HPA
AT 20.9N 120.7E BASHI CHANNEL MOVING SOUTHWEST 10 KNOTS.
POSITION FAIR.
MAX WINDS 30 KNOTS NEAR CENTER.

[supercane]

Latest ASCAT:

[dexterlabio]

WTPN31 PGTW 080900
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 11W (ELEVEN) WARNING NR 002
UPGRADED FROM TROPICAL DEPRESSION 11W
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
080600Z --- NEAR 21.2N 119.6E
MOVEMENT PAST SIX HOURS - 270 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND RADAR
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 21.2N 119.6E
---
FORECASTS:
12 HRS, VALID AT:
081800Z --- 21.9N 118.4E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 310 DEG/ 07 KTS
---
24 HRS, VALID AT:
090600Z --- 22.8N 117.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 335 DEG/ 07 KTS
---
36 HRS, VALID AT:
091800Z --- 24.1N 116.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 335 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
100600Z --- 25.5N 115.9E
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
080900Z POSITION NEAR 21.4N 119.3E.
TROPICAL STORM (TS) 11W (ELEVEN), LOCATED APPROXIMATELY 310 NM EAST
OF HONG KONG, HAS TRACKED WESTWARD AT 10 KNOTS OVER THE PAST SIX
HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY INDICATES IMPROVED
CONVECTIVE BANDING WRAPPING INTO A PARTIALLY-EXPOSED LOW-LEVEL
CIRCULATION CENTER (LLCC). ANIMATED WATER VAPOR IMAGERY INDICATES
IMPROVED OUTFLOW WITH A DEVELOPING ANTICYCLONE OVER THE CENTER AND
ENHANCED POLEWARD OUTFLOW INTO A TUTT CELL EAST OF TAIWAN. A 080209Z
ASCAT IMAGE DEPICTS NUMEROUS 30-35 KNOT WIND VECTORS AROUND THE
CENTER. DVORAK ESTIMATES RANGE FROM 30-35 KNOTS. RECENT SURFACE
OBSERVATIONS NEAR THE CENTER INDICATE SLP NEAR 995 MB AND 35-45 KNOT
SURFACE WINDS. THE CURRENT INTENSITY IS BASED PRIMARILY ON THE ASCAT,
DVORAK ESTIMATES AND SLP VALUE. OVERALL, THE SYSTEM IS CONSOLIDATING
AND WARRANTS UPGRADE TO TS STRENGTH BASED ON THE AVAILABLE EVIDENCE.
TS 11W IS EXPECTED TO TRACK NORTHWESTWARD ALONG THE SOUTHWEST
PERIPHERY OF THE LOW- TO MID-LEVEL SUBTROPICAL STEERING RIDGE
SITUATED ACROSS EASTERN CENTRAL CHINA. TS 11W IS EXPECTED TO PEAK AT
40-45 KNOTS AND SHOULD DISSIPATE OVER LAND BY TAU 48. MODEL
TRACKERS, WHICH ARE LIMITED TO NOGAPS, WBAR, GFDN AND GFS, PLUS
ECMWF AND UKMO FIELDS SUPPORT THIS FORECAST. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 080600Z IS 10 FEET. NEXT WARNINGS AT 081500Z, 082100Z,
090300Z AND 090900Z.//
NNNN

[Infdidoll]

New weather site for the West Pac you might want to bookmark:

http://www.westernpacificweather.com/

Good video analysis of the West Pac.

I didn't expect anything to come from this at all, but looks like it's got some good convection built...Somebody's in for a good storm, anyway.

[Chacor]

WTPQ21 RJTD 080900
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 080900UTC 20.0N 119.3E FAIR
MOVE WSW 09KT
PRES 1002HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 090900UTC 21.5N 116.9E 120NM 70%
MOVE WNW 07KT
PRES 996HPA
MXWD 035KT
GUST 050KT =

[KWT]

From supercanes image earlier on looks like there maybe two competing circulations with the stronger one clearly further east but the 2nd one which isn't closed is still trying to get going.

[supercane]

Advisory catch-up:
SUBJ: TROPICAL STORM 11W (ELEVEN) WARNING NR 004
WTPN31 PGTW 082100
1. TROPICAL STORM 11W (ELEVEN) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
081800Z --- NEAR 21.0N 118.9E
MOVEMENT PAST SIX HOURS - 280 DEGREES AT 05 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
REPEAT POSIT: 21.0N 118.9E
---
FORECASTS:
12 HRS, VALID AT:
090600Z --- 21.6N 117.9E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 320 DEG/ 06 KTS
---
24 HRS, VALID AT:
091800Z --- 22.5N 117.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 325 DEG/ 06 KTS
---
36 HRS, VALID AT:
100600Z --- 23.5N 116.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 335 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
101800Z --- 24.8N 115.6E
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
082100Z POSITION NEAR 21.2N 118.6E.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 081800Z IS 13 FEET.
NEXT WARNINGS AT 090300Z, 090900Z, 091500Z AND 092100Z.
//
BT
#0001
NNNN

WDPN31 PGTW 081500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 11W WARNING NR 03//
RMKS/
1. FOR METEOROLOGISTS.
2. 12 HOUR SUMMARY AND ANALYSIS.
A. TROPICAL STORM (TS) 11W (ELEVEN), LOCATED APPROXIMATELY 305 NM
EAST-SOUTHEAST OF HONG KONG, HAS TRACKED WESTWARD AT 08 KNOTS OVER
THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY INDICATES
A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) WITH DEEP
CONVECTIVE BANDING PRIMARILY OVER THE SOUTHERN SEMI-CIRCLE. ANIMATED
WATER VAPOR IMAGERY INDICATES THAT THE TUTT CELL, WHICH HAD PROVIDED
IMPROVED POLEWARD (EASTWARD) OUTFLOW, HAS TRACKED WEST OVER TAIWAN
AND IS PRODUCING WEAK TO MODERATE (10-15 KNOT) NORTHERLY VERTICAL
WIND SHEAR (VWS). A 080849Z SSMIS COMPOSITE IMAGE AND A 081059Z
AMSU IMAGE SHOW CURVED BANDING WRAPPING INTO THE EXPOSED LLCC,
WHICH IS LOCATED ON THE NORTHERN EDGE OF THE DEEP CONVECTION. RADAR
IMAGERY ALSO SUPPORTS THE CURRENT POSITION WITH GOOD CONFIDENCE.
THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES OF 35 KNOTS
FROM BOTH PGTW AND KNES AS WELL AS AN EARLIER 080211Z ASCAT IMAGE
SHOWING NUMEROUS 30-35 KNOT WIND VECTORS AROUND THE CENTER.
3. FORECAST REASONING.
A. NO CHANGE IN FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 11W IS TRACKING WESTWARD UNDER THE STEERING INFLUENCE OF
THE LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR), WHICH EXTENDS WESTWARD
ALONG 28-30N LATITUDE INTO EASTERN CHINA FROM A HIGH CENTERED NEAR
27N 140E. GFS IS INDICATING A SHARP TURN NORTHWARD AFTER TAU
12. MODEL FIELDS INDICATE GFS IS WEAKENING THE SYSTEM TOO RAPIDLY AND
IS LOSING THE CIRCULATION COMPLETELY BY TAU 36. NOGAPS IS TURNING
THE SYSTEM SHARPLY NORTHWARD AFTER TAU 24 AND ALSO WEAKENS THE
SYSTEM TOO RAPIDLY. NOGAPS/GFS ARE INITIALIZING THE STR WELL BUT
APPEAR TO BE WEAKENING THE STR TOO RAPIDLY, DRIVING THE SYSTEM
DIRECTLY INTO THE EXISTING STR. THIS HAS BEEN A CONTINUING PROBLEM
OVER THE PAST 24 HOURS. THE REMAINING MODELS (ECMWF, JGSM, GFDN AND
WBAR) ARE IN GOOD AGREEMENT AND INDICATE A NORTHWESTWARD TRACK THAT
MAKES SENSE WITH THE LATEST 500/700MB ANALYSIS OF THE STR. TS 11W IS
EXPECTED TO STRENGTHEN TO A PEAK INTENSITY OF 40 TO 45 KNOTS BY TAU
24 AS THE TUTT CELL WEAKENS AND NORTHERLY VWS DECREASES. THE SYSTEM
IS FORECAST TO MAKE LANDFALL BY TAU 36 AND WILL DISSIPATE BY TAU 48.
THE FORECAST TRACK IS FASTER THAN THE MODEL CONSENSUS AND LEFT OF
CONSENSUS DUE TO THE AFOREMENTIONED NOGAPS/GFS POLEWARD BIAS.//
NNNN

[supercane]

WTPN31 PGTW 082100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 11W (ELEVEN) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
081800Z --- NEAR 21.0N 118.9E
MOVEMENT PAST SIX HOURS - 280 DEGREES AT 05 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
REPEAT POSIT: 21.0N 118.9E
---
FORECASTS:
12 HRS, VALID AT:
090600Z --- 21.6N 117.9E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 320 DEG/ 06 KTS
---
24 HRS, VALID AT:
091800Z --- 22.5N 117.1E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 325 DEG/ 06 KTS
---
36 HRS, VALID AT:
100600Z --- 23.5N 116.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 48 HR POSIT: 335 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
101800Z --- 24.8N 115.6E
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
082100Z POSITION NEAR 21.2N 118.6E.
TROPICAL STORM (TS) 11W (ELEVEN), LOCATED APPROXIMATELY 280 NM
EAST-SOUTHEAST OF HONG KONG, HAS TRACKED WESTWARD AT 05 KNOTS OVER
THE PAST SIX HOURS. ANIMATED INFRARED (IR) IMAGERY REVEALS A
PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER WITH DEEP CONVECTION
SHEARING TO THE SOUTHEAST OF THE SYSTEM. THE CURRENT POSITION AND
PAST SIX HOUR MOTION ARE BASED ON ANIMATED IR IMAGERY WITH POOR
CONFIDENCE. THE CURRENT INTENSITY IS BASED ON DVORAK ESTIMATES FROM
PGTW AND KNES OF 35 KNOTS. UPPER LEVEL ANALYSIS INDICATES NORTH-
NORTHWESTERLY VERTICAL WIND SHEAR OVER THE SYSTEM, ASSOCIATED WITH
THE UPPER LEVEL LOW MOVING WESTWARD INTO EASTERN CHINA AND
CONTINUING TO IMPINGE POLEWARD OUTFLOW. TS 11W IS CURRENTLY TRACKING
ALONG THE SOUTHERN PERIPHERY OF A WESTERN EXTENSION OF A LOW TO MID-
LEVEL SUBTROPICAL STEERING RIDGE (STR) STATIONED SOUTH OF MAINLAND
JAPAN. TS 11W IS FORECAST TO INTENSIFY SLIGHTLY AND SLOWLY TURN
POLEWARD AS THE RIDGE IS WEAKENED BY AN APPROACHING MID-LATITUDE
TROUGH. THE SYSTEM IS EXPECTED TO MAKE LANDFALL BY TAU 36 AND
DISSIPATE AS A SIGNIFICANT TROPICAL CYCLONE BY TAU 48. NUMERICAL
MODEL GUIDANCE IS IN FAIR AGREEMENT, WITH THE EXCEPTION OF GFS WHICH
RAPIDLY WEAKENS THE STR AND DRIVES THE SYSTEM POLEWARD FASTER AND
SOONER. GFDN, WBAR, NGPS, ECMWF, AND JGSM MODEL TRACKERS HAVE ALL
SHIFTED SLIGHTLY EASTWARD FROM THE PREVIOUS 12Z TRACKERS, INDICATING
THE STEERING RIDGE MAY WEAKEN SOONER THEN PREVIOUSLY FORECAST. THIS
FORECAST IS CONSISTENT WITH THE PREVIOUS FORECAST AND REMAINS WEST
OF CONSENSUS TO ACCOUNT FOR THE AFOREMENTIONED GFS POLEWARD BIAS AND
UPPER AIR SOUNDINGS FROM HONG KONG, AND SHANTOU, CHINA INDICATING
EASTERLY FLOW. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 081800Z IS 13
FEET. NEXT WARNINGS AT 090300Z, 090900Z, 091500Z AND 092100Z.//
NNNN




WTPQ21 RJTD 082100
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 082100UTC 20.6N 118.8E FAIR
MOVE NW SLOWLY
PRES 1002HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 092100UTC 23.4N 118.1E 120NM 70%
MOVE N 07KT
PRES 996HPA
MXWD 035KT
GUST 050KT =




TXPN26 KNES 082142
SIMWIR
A. 11W (NONAME)
B. 08/2032Z
C. 21.1N
D. 118.9E
E. THREE/MTSAT
F. T3.0/3.0/D1.0/24HRS
G. IR/EIR
H. REMARKS...LLC HAS NOT MOVE MUCH OVER PAST FEW POSITIONS HOWEVER
CONVECTION HAS INCREASED AND DT=3.0 BASED ON SHEAR PATTERN. FT BASED
ON PT.
I. ADDL POSITIONS
NIL
...SWANSON
=