WPAC: TAPAH - Post-Tropical

[Hayabusa]

97W INVEST 250904 1200 16.4N 117.0E WPAC 15 0

[Hayabusa]

Now low

ABPW10 PGTW 050100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/050100Z-050600ZSEP2025//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/041951ZSEP2025//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 04SEP25 1800Z, TROPICAL STORM 21W (PEIPAH) WAS LOCATED NEAR
33.1N 132.8E, APPROXIMATELY 80 NM SOUTH-SOUTHEAST OF IWAKUNI, JAPAN, AND
HAD TRACKED NORTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. MAXIMUM
SUSTAINED SURFACE WINDS WERE ESTIMATED AT 35 KNOTS GUSTING TO 45 KNOTS.
SEE REF A (WTPN31 PGTW 042100) FOR FURTHER DETAILS.
(2) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION (INVEST 97W) HAS PERSISTED NEAR 17.3N
119.4E, APPROXIMATELY 58 NM WEST-SOUTHWEST OF VIGAN. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A WEAKLY DEFINED
CIRCULATION CENTER THAT IS OBSCURED BY FLARING CONVECTION IN THE
NORTHERN PERIPHERY OF 97W. ENVIRONMENTAL ANALYSIS FOR THE AREA INDICATES
A FAVORABLE CONDITIONS FOR DEVELOPMENT WITH 15-20 KTS OF VERTICAL WIND
SHEAR, WARM SEA SURFACE TEMPERATURES (29-30 C), AND MODERATE EQUATORWARD
OUTFLOW ALOFT. GLOBAL DETERMINISTIC MODELS ARE IN GOOD AGREEMENT THAT
97W WILL DEVELOP AND TRACK NORTHWARD SOUTHWEST OF TAIWAN, WITH GFS
INDICATING FASTER DEVELOPMENT. ENSEMBLES ARE IN GOOD AGREEMENT THAT 97W
WILL TRACK NORTHWARD WITH ECENS BEING THE MORE AGGRESSIVE AND FAVORS THE
DEVELOPMENT SOUTHWEST OF TAIWAN. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 13 TO 18 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO
BE NEAR 1009 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.
(2) NO OTHER SUSPECT AREAS.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.
3. JUSTIFICATION FOR REISSUE: ADDED LOW AREA IN PARA. 1.B.(1).//
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[Hayabusa]

Up to medium

ABPW10 PGTW 050600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS/050600Z-060600ZSEP2025//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/050151ZSEP2025//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 05SEP25 0000Z, TROPICAL STORM 21W (PEIPAH) WAS LOCATED NEAR
33.9N 135.5E, APPROXIMATELY 171 NM EAST OF IWAKUNI, JAPAN, AND HAD
TRACKED EAST-NORTHEASTWARD AT 24 KNOTS OVER THE PAST SIX HOURS. MAXIMUM
SUSTAINED SURFACE WINDS WERE ESTIMATED AT 40 KNOTS GUSTING TO 50 KNOTS.
SEE REF A (WTPN31 PGTW 050300) FOR FURTHER DETAILS.
(2) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR
17.3N 119.4E IS NOW LOCATED NEAR 18.0N 118.9E, APPROXIMATELY 373 NM
SOUTHEAST OF HONG KONG. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS A CONSOLIDATING CIRCULATION CENTER THAT IS OBSCURED BY FLARING
CONVECTION. 050133Z AND 050223Z ASCAT IMAGES REVEAL AN ELONGATED
CIRCULATION WITH A SWATH OF ELEVATED WINDS (15-20 KTS) ALONG THE EASTERN
SIDE OF THE SYSTEM. ENVIRONMENTAL ANALYSIS FOR THE AREA INDICATES A
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW TO MODERATE (15-20 KTS)
VERTICAL WIND SHEAR, WARM (29-30 C) SEA SURFACE TEMPERATURES, AND
MODERATE EQUATORWARD OUTFLOW ALOFT. ENSEMBLES ARE IN GOOD AGREEMENT THAT
97W WILL TRACK NORTHWESTWARD FROM THE WESTERN COASTLINE OF LUZON TOWARDS
MAINLAND CHINA AND CONTINUE TO DEVELOP OVER THE NEXT 48 HOURS. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20 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.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
C. SUBTROPICAL SYSTEM SUMMARY: NONE.//
NNNN

[Hayabusa]

TCFA

WTPN21 PGTW 051430
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 97W) //
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
110 NM EITHER SIDE OF A LINE FROM 17.4N 119.1E TO 19.4N 116.3E
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
IMAGERY AT 051200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 17.6N 118.7E. THE SYSTEM IS MOVING WESTWARD AT 02 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED NEAR
18.0N 118.9E IS NOW LOCATED NEAR 17.6N 118.7E, APPROXIMATELY 381.2 NM
SOUTHEAST OF HONG KONG. ANIMATED ENHANCED INFRARED IMAGERY (EIR) DEPICTS
A CONSOLIDATING CIRCULATION WITH A BAND OF FLARING CONVECTION JUST SOUTH
OF THE CENTER ASSISTING THE SYSTEM WITH A LINE OF CONVERGENCE DEEPENING
THE CONVECTION. A 051241Z METOP-B ASCAT IMAGE REVEALS 15-20 KT WINDS
FROM THE NORTHEAST AND THE SOUTHWEST BEGINNING TO WRAP CLOSER TO THE
CIRCULATION CENTER. ENVIRONMENTAL ANALYSIS FOR THE AREA INDICATES A
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW (10-15 KTS) VERTICAL WIND
SHEAR, WARM (30 C) SEA SURFACE TEMPERATURES, AND MODERATE EQUATORWARD
OUTFLOW ALOFT. ENSEMBLES ARE IN GOOD AGREEMENT THAT 97W WILL TRACK
NORTHWESTWARD TOWARDS MAINLAND CHINA WITH CONTINUED CONSOLIDATION OVER
THE NEXT 24 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15
TO 20 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 HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
061430Z.
//
NNNN

[Hayabusa]

Models track it near if not over Hong Kong as a strengthening storm

[Hayabusa]

TD a
Issued at 2025/09/05 19:10 UTC
Analysis at 09/05 18 UTC
Grade TD
Scale -
Intensity -
Center position N17°35′ (17.6°)
E117°35′ (117.6°)
Direction and speed of movement W 15 km/h (8 kt)
Central pressure 1004 hPa
Maximum sustained wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)

[Hayabusa]

22W TWENTYTWO 250906 0600 18.3N 116.7E WPAC 30 1002

[Hayabusa]

Jma upgrades to TS Tapah

[Hayabusa]

T2516(Tapah)
Issued at 2025/09/08 00:50 UTC
Analysis at 09/08 00 UTC
Grade TY
Scale -
Intensity -
Center position N21°10′ (21.2°)
E112°05′ (112.1°)
Direction and speed of movement NW 20 km/h (12 kt)
Central pressure 975 hPa
Maximum sustained wind speed near center 35 m/s (65 kt)
Maximum wind gust speed 50 m/s (95 kt)
Radius of 50-kt wind area 110 km (60 NM)
Radius of 30-kt wind area SE390 km (210 NM)
NW220 km (120 NM)