WPAC: KOMPASU - Post-Tropical

[Hayabusa]

The 2nd potential storm

93W INVEST 211003 0000 4.7N 148.7E WPAC 15 0

[Hayabusa]

I don't know if this is the one the GFS is showing the Marianas threat where it recurves or the Luzon threat, rather I'm still skeptical of the GFS solution that they would both develop.

[Hayabusa]

Euro 12Z

18Z

[Hayabusa]

Latest ensemble, Euro makes a dominant circulation nearer the Philippines and peaking 930 mb just before striking Luzon... but this ain't 93W(???), it doesn't really develop 93W.

Multimodel


close up

[Hayabusa]

Latest 06Z GFS still develops 93W, but I'm still skeptical of two TCs developing in such proximity, I'm thinking one invest would rip/swallow the other and becoming the dominant one. I guess it depends on where will future 94W form.

[Hayabusa]

06Z Ensemble, but the previous run Euro seems to make 93W the dominant one.

TXPQ27 KNES 041159
TCSWNP

A. TROPICAL DISTURBANCE (93W)

B. 04/1130Z

C. 4.7N

D. 143.7E

E. THREE/HIMAWARI-8

F. T1.5/1.5

G. IR/EIR/SWIR

H. REMARKS...THIS INTENSITY ESTIMATE WAS DERIVED USING 4 KM IR
DATA. 2.5/10 BANDING AROUND THE LLCC YIELDS A DT OF 1.5. MET IS EQUAL
TO 1.0 AND PT IS EQUAL TO 1.5. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...TUGGLE

[dexterlabio]

The model solutions look weird and funny for this one, as well for the future ones predicted to develop in the next 2 weeks.

[Hayabusa]

UKMET

[Hayabusa]

EPS, but the operational jumps to another center cause of multiple circulations

[Hayabusa]

From 92W run

[Hayabusa]

[Hayabusa]

WWJP27 RJTD 070000
WARNING AND SUMMARY 070000.
WARNING VALID 080000.
WARNING IS UPDATED EVERY 6 HOURS.
TROPICAL DEPRESSION 1002 HPA AT 14N 130E ALMOST STATIONARY.

[Hayabusa]

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS/070600Z-080600ZOCT2021//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(2) AN AREA OF CONVECTION (INVEST 93W) HAS PERSISTED NEAR
13.1N 131.4E, APPROXIMATELY 450NM WEST-NORTHWEST OF YAP. THIS SYSTEM
IS EMBEDDED WITHIN THE WESTERN PERIPHERY OF A MONSOON DEPRESSION
WITH STRONG, CONVERGENT LOW-LEVEL WESTERLIES OVER THE SOUTHERN
SEMICIRCLE. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS
AN ELONGATED DISTURBANCE WITH BROAD TURNING AND MULTIPLE VORTEXES.
MSI ALSO INDICATES A MID-LEVEL CIRCULATION CENTER NEAR 13.7N 129.0E,
HOWEVER, THERE IS NO EVIDENCE OF A DEFINED LLC AT THIS TIME. UPPER-
LEVEL ANALYSIS INDICATES A GENERALLY FAVORABLE ENVIRONMENT WITH GOOD
EQUATORWARD OUTFLOW AND LOW TO MODERATE VERTICAL WIND SHEAR. GLOBAL
MODELS INDICATE THIS MONSOON DEPRESSION WILL GRADUALLY CONSOLIDATE
INTO A TROPICAL STORM OVER THE NEXT 2-3 DAYS AS INVEST 93W MERGES
WITH INVEST 94W. THERE IS SIGNIFICANT UNCERTAINTY IN HOW THESE TWO
SYSTEMS WILL DEVELOP AND MERGE WITH HIGH UNCERTAINTY IN TRACK MOTION
AS WELL. 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 LOW.

[Hayabusa]

Issued at 2021/10/07 13:30 UTC
Analisys at 10/07 12 UTC
Category TD
Scale -
Intensity -
Center Position N12°40′(12.7°)
E128°30′(128.5°)
Direction and speed of movement Almost stationary
Central pressure 1004hPa
Maximum wind speed 15m/s(30kt)
Maximum wind gust speed 23m/s(45kt)
Forecast at 10/08 12 UTC
Category TS
Intensity -
Center of probability circle N13°40′(13.7°)
E130°50′(130.8°)
Direction and speed of movement ENE 10km/h(6kt)
Central pressure 998hPa
Maximum wind speed 18m/s(35kt)
Maximum wind gust speed 25m/s(50kt)
Radius of probability circle 165km(90NM)
Forecast at 10/09 12 UTC
Category TS
Intensity -
Center of probability circle N16°20′(16.3°)
E130°50′(130.8°)
Direction and speed of movement N 15km/h(7kt)
Central pressure 996hPa
Maximum wind speed 20m/s(40kt)
Maximum wind gust speed 30m/s(60kt)
Radius of probability circle 280km(150NM)
Forecast at 10/10 12 UTC
Category TS
Intensity -
Center of probability circle N19°0′(19.0°)
E127°30′(127.5°)
Direction and speed of movement NW 20km/h(10kt)
Central pressure 992hPa
Maximum wind speed 23m/s(45kt)
Maximum wind gust speed 35m/s(65kt)
Radius of probability circle 430km(230NM)
Forecast at 10/11 12 UTC
Category STS
Intensity -
Center of probability circle N20°0′(20.0°)
E122°40′(122.7°)
Direction and speed of movement W 20km/h(12kt)
Central pressure 990hPa
Maximum wind speed 25m/s(50kt)
Maximum wind gust speed 35m/s(70kt)
Radius of probability circle 590km(320NM)
Forecast at 10/12 12 UTC
Category TS
Intensity -
Center of probability circle N20°5′(20.1°)
E117°10′(117.2°)
Direction and speed of movement W 25km/h(13kt)
Central pressure 992hPa
Maximum wind speed 23m/s(45kt)
Maximum wind gust speed 35m/s(65kt)
Radius of probability circle 800km(440NM)

[Sciencerocks]

[Sciencerocks]

[Meow]

Huge...

T2118 ( KOMPASU )
Issued on 2021/10/08 16:05

<Analysis at 15 JST, 2021/10/08>
Scale Very large
Intensity/Category Tropical Storm
Center Position 13.8N 131.5E
Direction and speed of movement E 15km/h (9kt)
Central pressure 998hPa
Maximum wind speed 18m/s (35kt)
Maximum wind gust speed 25m/s (50kt)
≥ 30-kt wind area ALL 950km (500NM)
<Forecast for 15 JST, 2021/10/09>
Intensity/Category Tropical Storm
Center Position 16.5N 132.0E
Direction and speed of movement N 15km/h (8kt)
Central pressure 994hPa
Maximum wind speed 20m/s (40kt)
Maximum wind gust speed 30m/s (60kt)
Radius of probability circle 120km (65NM)
<Forecast for 15 JST, 2021/10/10>
Intensity/Category Tropical Storm
Center Position 17.9N 128.5E
Direction and speed of movement WNW 15km/h (9kt)
Central pressure 990hPa
Maximum wind speed 23m/s (45kt)
Maximum wind gust speed 35m/s (65kt)
Radius of probability circle 220km (120NM)
<Forecast for 15 JST, 2021/10/11>
Intensity/Category Severe Tropical Storm
Center Position 19.5N 124.1E
Direction and speed of movement WNW 20km/h (11kt)
Central pressure 985hPa
Maximum wind speed 25m/s (50kt)
Maximum wind gust speed 35m/s (70kt)
Radius of probability circle 330km (180NM)
<Forecast for 15 JST, 2021/10/12>
Intensity/Category Severe Tropical Storm
Center Position 19.2N 118.0E
Direction and speed of movement W 25km/h (14kt)
Central pressure 985hPa
Maximum wind speed 25m/s (50kt)
Maximum wind gust speed 35m/s (70kt)
Radius of probability circle 430km (230NM)
<Forecast for 15 JST, 2021/10/13>
Intensity/Category Severe Tropical Storm
Center Position 18.4N 112.9E
Direction and speed of movement W 20km/h (12kt)
Central pressure 985hPa
Maximum wind speed 25m/s (50kt)
Maximum wind gust speed 35m/s (70kt)
Radius of probability circle 590km (320NM)

[Hayabusa]

Huge...

T2118 ( KOMPASU )
Issued on 2021/10/08 16:05
https://i.imgur.com/7JxeujI.png
<Analysis at 15 JST, 2021/10/08>
Scale Very large

Indeed, when was the last time the "Very Large" scale was used? I think it was 2017 during Typhoon Lan.
Edit: 2019 Tropical Storm Krosa was the last time it was used.

[wxman57]

JMA's center is between 94W and 93W. They're moving the center NE to be associated with 94W. 93W will be absorbed by 94W (Kompasu). Complex very large low pressure area. TS winds are near 18N/136.5E, or about 380nm NE of JMA's position. On that visible satellite loop in a post above, you can see the weak swirl JMA is calling the center. It's starting to consolidate with 94W.

[Subtrop]

WTPN21 PGTW 081530
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 93W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
220 NM EITHER SIDE OF A LINE FROM 12.6N 131.9E TO 17.7N 129.9E
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 30 TO 35 KNOTS. METSAT IMAGERY AT
081500Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 12.6N
131.9E. THE SYSTEM IS MOVING EAST-NORTHEASTWARD AT 06 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED
NEAR 12.4N 131.3E IS NOW LOCATED NEAR 12.6N 131.9E, APPROXIMATELY
351NM NORTH-NORTHWEST OF PALAU. THIS SYSTEM IS CURRENTLY CLASSIFIED
AS A MONSOON DEPRESSION WITH EXPANSIVE GALE-FORCE WINDS OVER THE
EASTERN PERIPHERY OF THE SYSTEM. THE GALE-FORCE WINDS ARE LOCATED
OVER 300NM FROM THE BROAD, POORLY-DEFINED SYSTEM CENTER. AS IS
TYPICAL WITH MONSOON DEPRESSIONS, ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY AND A 080928Z SSMIS 91GHZ MICROWAVE IMAGE DEPICT
EXTENSIVE AREAS OF INTENSE DEEP CONVECTION OVER THE WESTERN,
SOUTHERN AND EASTERN PERIPHERIES WITH NO CENTRAL CONVECTION OVER THE
BROAD, POORLY-DEFINED LOW-LEVEL CIRCULATION. A 081025Z ASCAT-A
PARTIAL IMAGE REVEALS AN ELONGATED, WEAK CIRCULATION WITH 20-25 KNOT
WESTERLY WINDS OVER THE SOUTHERN SEMICIRCLE AND SHARP TROUGHING
EXTENDING NORTHEASTWARD INTO INVEST 94W, WHICH IS ROTATING AROUND
THE PERIPHERY OF INVEST 93W. UPPER-LEVEL ANALYSIS INDICATES A
MARGINAL ENVIRONMENT WITH CONVERGENT NORTHERLY FLOW OVER THE LLC AND
LOW TO MODERATE (10-20 KTS) VERTICAL WIND SHEAR. GLOBAL MODELS
INDICATE THAT THIS MONSOON DEPRESSION WILL STEADILY STRENGTHEN AS IT
TRACKS NORTHWARD TO NORTHWESTWARD OVER THE NEXT TWO DAYS. THE SYSTEM
IS EXPECTED TO GRADUALLY GAIN TROPICAL CYCLONE (WARM-CORE)
CHARACTERISTICS WITH IMPROVED CENTRAL CONVECTION AND A RADIUS OF
MAXIMUM WINDS LESS THAN 100NM. BASED ON THE PERIPHERAL WINDS IN
RECENT ASCAT IMAGERY, MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED
AT 30 TO 35 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE
NEAR 996 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
091530Z.//
NNNN