WPAC: JONGDARI - Post-Tropical

[Alyono]

landfall a couple of hours ago. Very heavy rains now occurring

[NotoSans]

Landfall intensity 65kt/975mb according to JMA.

[Alyono]

now looking likely to survive and move toward Shanghai

[shah83]

18z hwrf is impressive on its impacts in the Hangzhou Bay area.

[NotoSans]

Surprised to see JTWC insisting to forecast disspation when models are showing re-intensification within the next few days.

[xtyphooncyclonex]

JMA is now in line with the models.

I wonder what the JTWC guy has to say about being defiant.

[euro6208]

Looks like JTWC isn't too confident about regeneration but mentions the possibility.

WDPN35 PGTW 290900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (JONGDARI) WARNING
NR 30//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 15W (JONGDARI), LOCATED APPROXIMATELY 27 NM
SOUTHWEST OF IWAKUNI, JAPAN, HAS TRACKED WEST-SOUTHWESTWARD AT 15
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A RAPIDLY WEAKENING, PARTIALLY EXPOSED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH DEEP CONVECTION FLARING OVER THE WEST
QUADRANT. ANIMATED RADAR IMAGERY SHOWS A DEFINED LLCC WITH
FRAGMENTED, CURVED BANDING, ESPECIALLY OVER THE WESTERN SEMICIRCLE,
WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. THE SYSTEM
CENTER TRACKED ABOUT 13NM NORTH OF IWAKUNI (RJOI) AT 29/05Z WITH
MAXIMUM SUSTAINED EASTERLY WINDS OF 19 GUSTING TO 28 KNOTS AND
MINIMUM SLP OF 993.0MB. THIS GENERALLY SUPPORTS THE INITIAL
INTENSITY ESTIMATE OF 35 KNOTS. UPPER-LEVEL ANALYSIS REVEALS A
MARGINAL ENVIRONMENT WITH LOW VERTICAL WIND SHEAR AND CONVERGENT
FLOW OVER THE SYSTEM. ADDITIONALLY, INTERACTION WITH LAND IS A MAJOR
FACTOR IN THE RAPID WEAKENING TREND. TS 15W IS TRACKING CYCLONICALLY
AROUND THE NORTHERN PERIPHERY OF A BROAD, VERTICALLY STACKED LOW
SITUATED OVER WESTERN JAPAN WITH THE SUBTROPICAL RIDGE (STR)
POSITIONED TO THE NORTHWEST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. AS MENTIONED PREVIOUSLY, TS 15W IS EMBEDDED WITHIN THE
NORTHERN PERIPHERY OF A BROAD, BAROCLINIC LOW, WHICH REFLECTS DOWN
TO THE SURFACE. SURFACE DATA TO INCLUDE ASCAT, FEATURE TRACK WINDS
AND SURFACE OBSERVATIONS INDICATE THIS SURFACE LOW IS VERY LARGE,
ABOUT 1200NM DIAMETER, AND EXTENDS FROM THE KOREAN PENINSULA
SOUTHWARD ACROSS THE EAST CHINA SEA AND WESTERN JAPAN. SURFACE DATA
AS WELL AS 850MB VORTICITY PRODUCTS PROVIDE EVIDENCE OF A DEVELOPING
CIRCULATION / SECONDARY VORTICITY MAXIMA SOUTH OF SHIKOKU ISLAND.
THIS UNUSUAL, COMPLEX SYNOPTIC PATTERN WILL PROVIDE THE BASIS FOR
THE REMAINDER OF THE TS 15W FORECAST DISCUSSION. WITH THE EXCEPTION
OF EEMN, THE BULK OF THE NUMERICAL GUIDANCE NOW INDICATES THAT TS
15W WILL TRACK CYCLONICALLY AROUND THE WESTERN PERIPHERY OF THE LOW
AND WILL MERGE WITH THE SECONDARY LOW DEVELOPING SOUTH OF SHIKOKU.
TS 15W IS FORECAST TO CONTINUE WEAKENING AS IT TRACKS OVER LAND AND
WILL ALSO WEAKEN AS IT INTERACTS WITH THE CONVERGENT ENVIRONMENT
ASSOCIATED WITH THE DEEP BAROCLINIC LOW. THE CURRENT FORECAST
ANTICIPATES DISSIPATION BETWEEN TAU 36 AND 48. HOWEVER, THE
NUMERICAL MODELS INDICATE THE MERGED SYSTEM WILL RE-INTENSIFY AFTER
A PERIOD OF QUASI-STATIONARY TRACK MOTION AS IT TRACKS WESTWARD
TOWARD EASTERN CHINA AFTER TAU 72. IF THIS SCENARIO OCCURS, JTWC
WILL LIKELY REGENERATE 15W BUT NOT UNTIL THERE IS CLEAR EVIDENCE
THAT A DISTINCT TROPICAL SYSTEM EXISTS BASED ON ASCAT DATA AND
MICROWAVE IMAGERY. DESPITE THE COMPLEX PATTERN AND LARGE DEGREE OF
UNCERTAINTY, NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT. HOWEVER,
CONFIDENCE REMAINS LOW DUE TO THE UNCERTAINTY IN THE INTENSITY
FORECAST, TIMING AND DEGREE OF MERGER, AND EXTENDED TRACK FORECAST.//
NNNN

[euro6208]

Not looking too good right now...

[euro6208]

TPPN14 PGTW 290927

A. TROPICAL STORM 15W (JONDARI)

B. 29/0900Z

C. 33.71N

D. 131.00E

E. FIVE/HMWRI8

F. N/A

G. IR/EIR/VIS/MSI

H. REMARKS: 63A/PBO PRLY ORGNZD LLCC/ANMTN. DVORAK VALUES
UNAVAILABLE DUE TO LLCC OVER LAND.

I. ADDITIONAL POSITIONS:
29/0354Z 34.18N 131.73E AMS2


LOWE

[euro6208]

[euro6208]

JMA is now in line with the models.

I wonder what the JTWC guy has to say about being defiant.

Yup the so called not official agency but gains more attention worldwide.

[euro6208]

Still optimistic about development...

WDPN35 PGTW 291500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 15W (JONGDARI)
WARNING NR 31//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 15W (JONGDARI), LOCATED APPROXIMATELY 42
NM EAST-NORTHEAST OF SASEBO, JAPAN, HAS TRACKED SOUTHWESTWARD AT 12
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A RAPIDLY WEAKENING LOW-LEVEL CIRCULATION CENTER
(LLCC) WITH LIMITED DEEP CONVECTION FLARING OVER THE SOUTHERN
SEMICIRCLE. ANIMATED RADAR IMAGERY SHOWS A DETERIORATING LLCC WITH
FRAGMENTED CONVECTIVE BANDING AND A WEAKLY DEFINED LLCC, WHICH
SUPPORTS THE INITIAL POSITION WITH FAIR CONFIDENCE. THE INITIAL
INTENSITY IS ASSESSED AT 30 KNOTS BASED ON THE WEAK OVERALL
STRUCTURE. UPPER-LEVEL ANALYSIS REVEALS A MARGINAL ENVIRONMENT WITH
LOW VERTICAL WIND SHEAR AND CONVERGENT FLOW OVER THE SYSTEM.
ADDITIONALLY, INTERACTION WITH LAND IS A MAJOR FACTOR IN THE RAPID
WEAKENING TREND. TD 15W IS TRACKING CYCLONICALLY AROUND THE NORTHERN
PERIPHERY OF A BROAD, VERTICALLY STACKED LOW SITUATED OVER WESTERN
JAPAN WITH THE SUBTROPICAL RIDGE POSITIONED TO THE NORTHWEST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. AS MENTIONED PREVIOUSLY, TD 15W IS EMBEDDED WITHIN THE
NORTHERN PERIPHERY OF A BROAD, BAROCLINIC LOW, WHICH REFLECTS DOWN
TO THE SURFACE. SURFACE DATA TO INCLUDE ASCAT, FEATURE TRACK WINDS
AND SURFACE OBSERVATIONS INDICATE THIS SURFACE LOW IS VERY LARGE,
ABOUT 1200NM DIAMETER, AND EXTENDS FROM THE KOREAN PENINSULA
SOUTHWARD ACROSS THE EAST CHINA SEA AND WESTERN JAPAN. SURFACE DATA
AS WELL AS 850MB VORTICITY PRODUCTS PROVIDE EVIDENCE OF A DEVELOPING
CIRCULATION / SECONDARY VORTICITY MAXIMA (INVEST 91W) SOUTH OF
SHIKOKU ISLAND. THIS UNUSUAL, COMPLEX SYNOPTIC PATTERN WILL PROVIDE
THE BASIS FOR THE REMAINDER OF THE TD 15W FORECAST DISCUSSION. THE
NUMERICAL GUIDANCE NOW INDICATES THAT TD 15W WILL TRACK CYCLONICALLY
AROUND THE WESTERN PERIPHERY OF THE LOW AND WILL MERGE WITH THE
SECONDARY LOW DEVELOPING SOUTH OF SHIKOKU. TD 15W IS FORECAST TO
CONTINUE WEAKENING AS IT TRACKS OVER LAND AND WILL ALSO WEAKEN AS IT
INTERACTS WITH THE CONVERGENT ENVIRONMENT ASSOCIATED WITH THE DEEP
BAROCLINIC LOW. THE CURRENT FORECAST ANTICIPATES DISSIPATION BY TAU
36. HOWEVER, THE NUMERICAL MODELS INDICATE THE MERGED SYSTEM WILL RE-
INTENSIFY AFTER A PERIOD OF QUASI-STATIONARY TRACK MOTION AS IT
TRACKS WESTWARD TOWARD EASTERN CHINA AFTER TAU 48. IF THIS SCENARIO
OCCURS, JTWC WILL LIKELY REGENERATE 15W BUT NOT UNTIL THERE IS CLEAR
EVIDENCE THAT A DISTINCT TROPICAL SYSTEM EXISTS BASED ON ASCAT DATA
AND MICROWAVE IMAGERY. DESPITE THE COMPLEX PATTERN, NUMERICAL MODEL
GUIDANCE IS IN FAIR AGREEMENT. HOWEVER, CONFIDENCE REMAINS LOW DUE
TO THE UNCERTAINTY IN THE INTENSITY FORECAST, TIMING AND DEGREE OF
MERGER, AND EXTENDED TRACK FORECAST.//
NNNN

[Alyono]

GFS has a very strong typhoon going up the Hangzhou Bay

[xtyphooncyclonex]

JMA is now in line with the models.

I wonder what the JTWC guy has to say about being defiant.

Yup the so called not official agency but gains more attention worldwide.

Gains more attention worldwide? Perhaps that is subjective. That's from your point of view. Probably worldwide pertains to the West.

Please be realistic. Even the JTWC's model depicts a strong typhoon. Most models don't just expect regeneration, but they note RI

[euro6208]

WDPN35 PGTW 292100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 15W (JONGDARI)
WARNING NR 32//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 15W (JONGDARI), LOCATED APPROXIMATELY 72 NM
SOUTH OF SASEBO, JAPAN, HAS TRACKED SOUTH-SOUTHWESTWARD AT 16 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A PARTIALLY EXPOSED LOW-LEVEL CIRCULATION CENTER
(LLCC) WITH FLARING DEEP CONVECTION, LIMITED TO THE SOUTHERN
SEMICIRCLE. ANIMATED RADAR IMAGERY SHOWS A BROAD LLCC WITH
FRAGMENTED CONVECTIVE BANDING STARTING TO WRAP AROUND A WEAKLY
DEFINED LLCC. THE INITIAL POSITION IS PLACED WITH POOR CONFIDENCE
BASED ON THE WEAK LLCC. THE INITIAL INTENSITY IS ASSESSED AT 30
KNOTS BASED ON THE PGTW AND RJTD DVORAK CURRENT INTENSITY ESTIMATES
OF T2.0 (30 KNOTS) AND T2.5 (35 KNOTS) RESPECTIVELY. UPPER-LEVEL
ANALYSIS REVEALS A MARGINALLY FAVORABLE ENVIRONMENT WITH LOW
VERTICAL WIND SHEAR (10-15 KNOT) BEING OFFSET BY UPPER LEVEL
CONVERGENCE OVER THE SYSTEM. TD 15W IS TRACKING CYCLONICALLY AROUND
THE NORTHERN PERIPHERY OF A BROAD, VERTICALLY STACKED LOW LOCATED
SOUTHEAST OF JAPAN.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE, HOWEVER, THE STORM IS NO
LONGER EXPECTED TO DISSIPATE BELOW 25 KNOTS BEFORE RE-INTENSIFYING.
THE FORECAST HAS BEEN EXTENDED TO 120 HOURS INSTEAD OF DISSIPATING
OVER WATER AT TAU 36.
B. THERE ARE THREE SIGNIFICANT CIRCULATIONS IMPACTING THE TRACK
AND INTENSITY OF TD 15W, MAKING FOR AN EXTREMELY COMPLEX
ENVIRONMENT. IN THE SHORT TERM (THROUGH TAU 36), STEERING FOR TD 15W
IS PRIMARILY DRIVEN BY THE LOW PRESSURE MENTIONED ABOVE. FOR THIS
PERIOD, THE TRACK IS QUASI-STATIONARY WHILE THE CYCLONE GRADUALLY
INTENSIFIES. ADDITIONALLY, A SECONDARY 850MB VORTICITY MAXIMUM
(INVEST 91W) WILL ROTATE CYCLONICALLY AND MERGE WITH 15W BY TAU 36.
THIS SECONDARY CIRCULATION CONTRIBUTES TO THE LOOP DEPICTED IN THE
FORECAST TRACK. AFTER TAU 36, A SUBTROPICAL RIDGE (STR) OVER CHINA
WILL DOMINATE AND THE TRACK WILL SHIFT WESTWARD. DURING THIS PERIOD,
THE CYCLONE WILL INTENSIFY TO REACH 60 KNOTS BY TAU 72. DESPITE THE
GUIDANCE BEING IN FAIR AGREEMENT THROUGH TAU 72, CONFIDENCE IN THE
FORECAST TRACK IS LOW DUE TO THE COMPLEXITY OF THE ENVIRONMENT.
C. BEYOND TAU 72, THE STR WILL CONTINUE TO DOMINATE THE STEERING
AND TD 15W WILL FOLLOW A WESTWARD TRACK UNTIL MAKING LANDFALL NEAR
SHANGHAI JUST AFTER TAU 96. AFTER MAKING LANDFALL, THE CYCLONE IS
EXPECTED TO WEAKEN SIGNIFICANTLY DUE TO LAND INTERACTION AND
DECREASE TO AN INTENSITY OF 35 KNOTS BY TAU 120. ALTHOUGH NUMERICAL
MODEL GUIDANCE REMAINS IN FAIR AGREEMENT, THERE IS CONSIDERABLE
SPREAD IN TRACK SPEED AND DIRECTION. THEREFORE, CONFIDENCE REMAINS
LOW IN THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

[galaxy401]

Not often we get a potential typhoon hitting Shanghai from the east.

[euro6208]

TPPN14 PGTW 292159

A. TROPICAL DEPRESSION 15W (JONGDARI)

B. 29/2100Z

C. 31.27N

D. 129.53E

E. FIVE/HMWRI8

F. T1.5/2.0/W2.5/30HRS STT: D0.0/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 49A/PBO PTLY XPSD LLCC/ANMTN. CNVCTN WRAPS .30 ON
LOG10 SPIRAL YIELDING A DT OF 1.5. NO MET/PT DUE TO LLCC OVER
LAND 24 HRS PRIOR. DBO DT.

I. ADDITIONAL POSITIONS: NONE


ZOUFALY

[euro6208]

[euro6208]

TPPN14 PGTW 300033

A. TROPICAL DEPRESSION 15W (JONGDARI)

B. 30/0000Z

C. 31.07N

D. 129.33E

E. FIVE/HMWRI8

F. T2.0/2.5 STT: D0.5/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 49A/PBO PTLY XPSD LLCC/ANMTN. CNVCTN WRAPS .35 ON
LOG10 SPIRAL YIELDING A DT OF 2.0. NO MET/PT DUE TO LLCC OVER
LAND 24 HRS PRIOR. DBO DT. *NOTE - 29/1800Z AND 29/2100Z FIXES
REANALYZED TO INCREASE CI (T1.5/2.5).*

I. ADDITIONAL POSITIONS:
29/1922Z 31.63N 129.27E SSMS
29/2234Z 31.17N 129.42E SSMS


ZOUFALY