WPAC: TD (ex-Typhoon Fung-wong) inland in China

[Chacor]

This has actually been out there a while now, near 22N 135E. Looks remotely subtropical to me — convection displaced from a hollow centre.

[Chacor]

JTWC TWO:

THE AREA OF CONVECTION LOCATED NEAR 22.0N 139.0E, IS NOW
LOCATED NEAR 22.0N 137.3E, APPROXIMATELY 590 NM EAST-SOUTHEAST OF
OKINAWA, JAPAN. ANIMATED INFRARED SATELLITE IMAGERY INDICATES A
PARTIALLY-EXPOSED BUT IMPROVING LOW-LEVEL CIRCULATION CENTER (LLCC)
WITH FORMATIVE CONVECTIVE BANDING ALONG THE SOUTH QUADRANT. A 210046Z
ASCAT IMAGE SHOWED 10 TO 15 KNOT WINDS NEAR THE POSITION OF THE LLCC.
THE DISTURBANCE REMAINS COLD-CORE BUT INDICATIONS SHOW THAT IT MAY BE
IN THE EARLY STAGES OF TRANSITIONING TO A WARM-CORE SYSTEM. THE EN-
VIRONMENT IS MARGINAL DUE TO THE COLD-CORE NATURE OF THE DISTURBANCE,
HOWEVER VERTICAL WIND SHEAR IS WEAK OVER THE LLCC AND SST IS GREATER
THAN 28C. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15
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 REMAINS POOR.

[Chacor]

LOW PRESSURE AREA 1004 HPA NEAR 22N 137E WNW SLOWLY.

[Chacor]

LOW PRESSURE AREA 1004 HPA NEAR 22N 136E WEST 10 KT.

[Ed Mahmoud]

I didn't exit the chartered Flying Tigers 747 flying from LAX to Cubi Point NAS, RP via Anchorage and Okinawa, but I did see an SR-71 Blackbird on the tarmac through my window at Okinawa.


By cold core, I assume they mean a piece of a TUTT low that cut off, because I can't imagine any other way a cold core low gets down near 20ºN this time of the year in the WestPac.

I could be wrong.

[Chacor]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 22.0N
139.0E, IS NOW LOCATED NEAR 23.1N 135.3E, APPROXIMATELY 455 NM EAST-
SOUTHEAST OF NAHA, OKINAWA. RECENT ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS LARGE SCALE UPPER LEVEL CYCLONIC TURNING WITH DEEP
CONVECTION PRESENT ALONG THE WESTERN PERIPHERY OF THE TURNING. IN
ADDITION, LOW LEVEL CLOUD LINES SHOW LESS PRONOUNCED TURNING NEAR
THE SURFACE. A 212317Z SSMIS MICROWAVE IMAGE REVEALS WEAK AND
RELATIVELY NEW FORMATIVE BANDING WITHIN THE WESTERN QUADRANTS OF THE
SYSTEM IN ASSOCIATION WITHIN THE TIGHTEST TURNING. A 212056Z
QUIKSCAT PASS SHOWS A WEAK LOW LEVEL CIRCULATION CENTER (LLCC) WITH
10 TO 15 KNOT UNFLAGGED WINDS NEAR THE SYSTEM CENTER. A MORE RECENT
220026Z PARTIAL ASCAT PASS CONFIRMS LITTLE CHANGE IN STORM INTENSITY
NEAR THE LLCC. HOWEVER, BOTH SCATTEROMETRY SOURCES SHOW WINDS IN
EXCESS OF 20 KNOTS ON THE OUTER PERIPHERY OF THE STORM, ESPECIALLY
WITHIN THE WESTERN SEMICIRCLE. UPPER LEVEL ANALYSIS INDICATES
CONVERGENCE ALOFT, WHICH IS LIMITING VERTICAL MOTION AND FURTHER
DEVELOPMENT. THE STORM HAS ALSO MOVED INTO AN AREA OF HIGHER
NORTHEASTERLY VERTICAL WIND SHEAR NEAR 20 KNOTS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. DUE TO THE BROAD AND
AMBIGUOUS STRUCTURE OF THE STORM, AND POOR UPPER LEVEL ENVIRONMENT,
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS REMAINS POOR.

[Chacor]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 23.1N
135.3E IS NOW LOCATED NEAR 22.2N 132.3E, APPROXIMATELY 400 NM SOUTH-
EAST OF NAHA, OKINAWA. RECENT ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS LOW LEVEL CLOUD LINES SPIRALLING INTO A TIGHTENING
LOW LEVEL CIRCULATION CENTER (LLCC) ALSO EVIDENT IN A 212304Z
SSMIS PASS. A 220915Z QUIKSCAT IMAGE INDICATES WEAK WINDS
AT THE CORE OF THE SYSTEM, WITH WINDS IN EXCESS OF 20 KNOTS ALONG
THE OUTER PERIPHERY. SHALLOW CONVECTION HAS PERSISTED ALONG A LINE
OF FORMATIVE BANDING ALONG THE WESTERN PERIPHERY OF THE CIRCULATION.
HOWEVER, THE CIRCULATION REMAINS ALMOST COMPLETELY DEVOID OF
ASSOCIATED DEEP CONVECTION NEAR THE CENTER. UPPER LEVEL ANALYSIS
SUGGESTS THAT AN UPPER LEVEL CYCLONE PREVIOUSLY SUPERIMPOSED ABOVE
THE LLCC HAS PROGRESSED WESTWARD AND THAT ANTICYCLONIC FLOW MAY BE
DEVELOPING ALOFT. THIS POTENTIAL FOR IMPROVED UPPER LEVEL FLOW
COULD SPARK NEW CONVECTIVE DEVELOPMENT. MAXIMUM SUSTAINED SURFACE
WINDS NEAR THE CENTER OF THE DISTURBANCE ARE ESTIMATED AT 10 TO 15
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB.
DUE TO THE LACK OF PERSISTENT DEEP CONVECTION AND POOR UPPER LEVEL
SUPPORT, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS REMAINS POOR.

JMA: TROPICAL DEPRESSION 1002 HPA AT 22N 133E WNW SLOWLY.

[Chacor]

TROPICAL DEPRESSION 1002 HPA AT 22N 132E ALMOST STATIONARY.

[Chacor]

Looking much better today.



WARNING.
TROPICAL DEPRESSION 1002 HPA
AT 21.5N 132.4E SEA SOUTH OF JAPAN ALMOST STATIONARY.
POSITION POOR.
MAX WINDS 30 KNOTS NEAR CENTER.

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 22.2N
132.3E, IS NOW LOCATED NEAR 21.4N 132.7E, APPROXIMATELY 400 NM
SOUTHEAST OF OKINAWA, JAPAN. ANIMATED INFRARED SATELLITE IMAGERY AND
A 231956Z SSMI IMAGE INDICATE IMPROVED CONSOLIDATION OF THE LOW-
LEVEL CIRCULATION CENTER (LLCC) OVER THE PAST 12 HOURS WITH
PERSISTENT CONVECTIVE BANDING ALONG THE SOUTHERN PERIPHERY. RECENT
SCATTEROMETER AND SURFACE DATA SHOW THAT THE LLCC IS EMBEDDED WITHIN
A MONSOON DEPRESSION WITH STRONGER WINDS ALONG THE SOUTHERN SEMI-
CIRCLE. UPPER-LEVEL ANALYSIS DEPICTS A MARGINAL, BUT IMPROVING,
ENVIRONMENT WITH WEAK TO MODERATE VERTICAL WIND SHEAR AND FAIR
DIFFLUENCE ALOFT. THE MODELS INDICATE THAT THE UPPER-LEVEL TROUGH
(CURRENTLY INHIBITING CONVECTION OVER THE NORTH SEMI-CIRCLE) WILL
WEAKEN LEAVING BROAD DIFFLUENT, EASTERLY FLOW WHICH SHOULD ALLOW THE
SYSTEM TO DEVELOP FURTHER. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 12 TO 18 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1003 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO
FAIR.

[HURAKAN]

It looks more tropical today.

[Chacor]

WARNING.
TROPICAL DEPRESSION 1002 HPA
AT 22.4N 134.0E SEA SOUTH OF JAPAN ALMOST STATIONARY.
POSITION POOR.
MAX WINDS 30 KNOTS NEAR CENTER.

[RL3AO]

PAGASA names it TD Igme



Severe Weather Bulletin Number ONE
Tropical Cyclone Alert: Tropical Depression "IGME"
Issued at 11:30 a.m., Thursday, 24 July 2008 The active low pressure area inside the Philippine Area of Responsibility (PAR) has formed into a tropical depression and was named "IGME".
Location of Center:
(as of 10:00 a.m.) 1,060 kms East Northeast of Basco, Batanes
Coordinates: 21.8°N, 132.8°E
Strength: Maximum sustained winds of 60 kph near the center
Movement: West Northwest at 07 kph
Forecast Positions/Outlook: Friday morning:
920 kms East Northeast of Basco, Batanes
Saturday morning:
780 kms East Northeast of Basco, Batanes
Sunday morning:
650 kms Northeast of Basco, Batanes

[Typhoon Hunter]

JTWC have just issued a TCFA for this system. It's looking a lot better than it was yesterday. Maybe another one for Taiwan, a few of the models certainly think so.

WTPN21 PGTW 240600
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 21.0N 132.9E TO 22.0N 127.3E
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 15 TO 20 KNOTS. METSAT IM-
AGERY AT 240530Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 21.1N 132.6E. THE SYSTEM IS MOVING WEST-SOUTHWESTWARD AT 02
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 21.4N
132.7E, IS NOW LOCATED NEAR 21.1N 132.5E, APPROXIMATELY 405 NM
SOUTHEAST OF OKINAWA, JAPAN. ANIMATED INFRARED SATELLITE IMAGERY AND
A 232252Z SSMIs IMAGE INDICATE IMPROVED CONSOLIDATION OF THE LOW-
LEVEL CIRCULATION CENTER (LLCC) OVER THE PAST 12 HOURS WITH
PERSISTENT CONVECTIVE BANDING ALONG THE SOUTHERN PERIPHERY. RECENT
SCATTEROMETER AND SURFACE DATA SHOW THAT THE LLCC IS EMBEDDED WITHIN
A MONSOON DEPRESSION WITH STRONGER WINDS ALONG THE SOUTHERN SEMI-
CIRCLE. UPPER-LEVEL ANALYSIS DEPICTS A MARGINAL, BUT IMPROVING,
ENVIRONMENT WITH WEAK TO MODERATE VERTICAL WIND SHEAR AND FAIR
DIFFLUENCE ALOFT. THE MODELS INDICATE THAT THE UPPER-LEVEL TROUGH
(CURRENTLY INHIBITING CONVECTION OVER THE NORTH SEMI-CIRCLE) WILL
WEAKEN LEAVING BROAD DIFFLUENT, EASTERLY FLOW WHICH SHOULD ALLOW THE
SYSTEM TO DEVELOP FURTHER. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1002 MB. DUE TO ENHANCED CONVECTION AND AN IMPROVED LLCC,
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO GOOD. SEE REF A (WTPN21 PGTW
240600) FOR FURTHER DETAILS.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
250600Z.//

[Typhoon Hunter]

JMA now forecasting a TS within 24 hours:

WTPQ20 RJTD 240600
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 240600UTC 22.4N 133.2E POOR
MOVE ALMOST STATIONARY
PRES 1000HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 250600UTC 23.8N 131.9E 120NM 70%
MOVE NW SLOWLY
PRES 996HPA
MXWD 035KT
GUST 050KT =

[Chacor]

Nice storm.





Rapid intensification possible?

[Typhoon Hunter]

Convection has really exploded over the last few hours. ECMWF, CWB and UKMET all take this into Taiwan at the moment. As ever I'll be keeping a close eye on this.

[Chacor]

WTPQ20 RJTD 241200
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 241200UTC 22.0N 132.3E POOR
MOVE W SLOWLY
PRES 998HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 251200UTC 22.5N 129.5E 70NM 70%
MOVE W 07KT
PRES 992HPA
MXWD 045KT
GUST 065KT =

[Chacor]

Here's the JTWC's 1500z discussion (prognostic reasoning):

TROPICAL DEPRESSION (TD) 09W IS TRACKING WEST-NORTHWESTWARD AT 02
KNOTS AND HAS SLOWLY INTENSIFIED OVER THE PAST 12 HOURS, REACHING
WARNING STRENGTH AT 141200Z. THE SYSTEM IS EMBEDDED WITHIN A BROAD
MONSOON DEPRESSION WITH STRONGER WINDS ALONG THE SOUTHERN PERIPHERY
OF THE DISTURBANCE. AN UPPER-LEVEL TROUGH HAS INHIBITED DEVELOPMENT
OVER THE NORTHERN SEMI-CIRCLE, CONFINING THE MAJORITY OF THE DEEP
CONVECTION TO THE SOUTHERN HEMISPHERE OF THE SYSTEM. MULTIPLE CON-
VECTIVE BANDS HAVE DEVELOPED ALONG THE SOUTHERN PERIPHERY OF THE
CYCLONE PROVIDING FAVORABLE EQUATORWARD OUTFLOW.

TD 09W IS TRACKING UNDER THE STEERING INFLUENCE OF THE LOW- TO
MID-LEVEL RIDGE POSITIONED NORTH OF THE SYSTEM. THE CURRENT POSITION
IS BASED ON ANIMATED INFRARED SATELLITE IMAGERY AND A 241008Z 37H
SSMIS IMAGE WHICH DEPICT A MARKED IMPROVMENT IN THE CONSOLIDATION
OF THE LOW-LEVEL CIRCULATION CENTER (LLCC) AS EVIDENCED BY THE DEEP
CONVECTION AND PERSISTENT BANDING ALONG THE SOUTHERN PERIPHERY OF TD
09W. UPPER-LEVEL ANALYSIS SHOWS AN IMPROVING ENVIRONMENT AS THE PREV-
IOUSLY MENTIONED TROUGH WEAKENS AND PROPAGATES WESTWARD AHEAD OF THE
SYSTEM LEAVING IN ITS WAKE AN AREA OF WEAK TO MODERATE VERTICAL WIND
SHEAR AND FAIR DIFFLUENCE ALOFT. THE CURRENT INTENSITY IS BASED ON A
COMBINATION OF A 241001Z PARTIAL QSCAT PASS DEPICTING UNFLAGGED WINDS
OF 20 KNOTS JUST EAST OF THE LLCC AND DVORAK ESTIMATES OF 30 KNOTS
FROM KNES AND RJTD.

THIS IS THE FIRST PROGNOSTIC REASONING FOR TD 09W.

TD 09W IS EXPECTED TO TRACK GENERALLY WESTWARD THROUGH TAU 72
UNDER THE CONTINUED INFLUENCE OF THE LOW- TO MID-LEVEL RIDGE TO THE
NORTH OF THE SYSTEM. THE WEAK UPPER-LEVEL TROUGH WHICH HAD BEEN
INHIBITING CONVECTION OVER THE NORTHERN SEMI-CIRCLE WILL CONTINUE
WEAKENING AND MOVING WESTWARD AHEAD OF THE DISTURBANCE ALLOWING THE
RESULTING BROAD, DIFFLUENT, EASTERLY FLOW TO PROVIDE A MORE FAVORABLE
UPPER LEVEL ENVIRONMENT FOR DEVELOPMENT. A MILD STRENGTHENING OF THE
STEERING RIDGE WILL INDUCE A GRADUAL INCREASE IN FORWARD TRACK SPEED,
AS TD 09W INTENSIFIES SLOWLY UNDER ENHANCED OUTFLOW ASSOCIATED WITH
A CONTINUALLY IMPROVING UPPER LEVEL ENVIRONMENT THROUGH TAU 72.

AFTER TAU 72, THE SYSTEM WILL BEGIN TRACKING NORTHWESTWARD TOWARDS
A WEAKNESS IN THE STEERING RIDGE AS AN APPROACHING MID-LEVEL TROUGH
MOVES OFF OF MAINLAND CHINA INTO THE YELLOW SEA. TD 09W IS EXPECTED
TO BEGIN A STEADY WEAKENING TREND NEAR TAU 96 AS LAND INTERACTION
OVER TAIWAN DISRUPTS THE STRUCTURE OF THE STORM. BEYOND TAU 96, A
DECREASE IN OCEAN HEAT CONTENT OVER THE WATERS OF THE TAIWAN
STRAIT COUPLED WITH INCREASED LAND INTERACTION WILL WEAKEN THE
SYSTEM SIGNIFICANTLY AS IT MAKES LANDFALL OVER EASTERN CHINA NEAR TAU
120. THE DYNAMIC AIDS ARE IN GOOD AGREEMENT WITH BOTH THE EXPECTED
TRACK AND INTENSITIES THROUGHOUT THE ENTIRE NEAR-TERM AND EXTENDED
FORECAST PERIODS.

FORECAST TEAM: DELTA//

[Chacor]

Very impressive.

[HURAKAN]

More rain for Taiwan.