WPAC: PEIPAH - Post-Tropical

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95W INVEST 250829 0600 10.0N 131.0E WPAC 15 0

[Hayabusa]

Latest GFS possibly makes a one system from these two invests...

[Hayabusa]

Now low

ABPW10 PGTW 301800
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/301800Z-310600ZAUG2025//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/301351ZAUG2025//
AMPN/REF A IS A TROPICAL CYCLONE FINAL WARNING.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 30AUG25 1200Z, TROPICAL DEPRESSION 20W (NONGFA) WAS LOCATED
NEAR 18.0N 104.4E, APPROXIMATELY 199 NM SOUTH-SOUTHWEST OF HANOI,
VIETNAM, AND HAD TRACKED WESTWARD AT 21 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 25 KNOTS GUSTING TO 35
KNOTS. SEE REF A (WTPN31 PGTW 301500) FOR THE FINAL WARNING ON THIS
SYSTEM.
(2) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION (INVEST 95W) HAS PERSISTED NEAR 10.4N
133.2E, APPROXIMATELY 204 NM NORTH-NORTHWEST OF PALAU. ANIMATED ENHANCED
INFRARED SATELLITE IMAGERY (EIR) DEPICTS FLARING CONVECTION ALONG THE
SOUTH-SOUTHEASTERN PERIPHERY OF THE POORLY ORGANIZED CIRCULATION CENTER
(LLCC). A 301213Z ASCAT IMAGE REVEALS 15-20 KNOT WINDS TO THE SOUTHWEST
PERIPHERY OF 93W. ENVIRONMENTAL ANALYSIS FOR THE AREA INDICATES
FAVORABLE CONDITIONS FOR DEVELOPMENT WITH LOW VERTICAL WIND SHEAR (10-15
KTS), WARM SEA SURFACE TEMPERATURES (30-31 C), AND MODERATE EQUATORWARD
OUTFLOW ALOFT. GLOBAL DETERMINISTIC MODELS ARE IN FAIR AGREEMENT THAT
95W HAS A CHANCE FOR DEVELOPMENT IN THE NEXT 48 HOURS TRACKING NORTH,
WITH GFS BEING THE MORE AGGRESSIVE. ENSEMBLE MODELS ARE IN AGREEMENT AS
WELL FOR A NORTHERN TRACK WITH GEFS BEING THE MORE AGGRESSIVE. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 13 TO 18 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 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).//
NNNN

[Hayabusa]

TCFA and JMA TC warning

WTPN21 PGTW 021500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 95W//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
180 NM EITHER SIDE OF A LINE FROM 21.0N 131.8E TO 30.0N 130.6E
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 20 TO 25 KNOTS. METSAT
IMAGERY AT 021430Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 21.8N 132.0E. THE SYSTEM IS MOVING NORTH-NORTHEASTWARD AT 13
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 95W) PREVIOUSLY LOCATED NEAR
19.9N 131.8E IS NOW LOCATED NEAR 21.8N 132.0E, APPROXIMATELY 356 NM
SOUTHEAST OF KADENA, JAPAN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) DEPICTS A BROAD AREA OF TROUGHING WITH PERSISTENT CONVECTION. A
RECENT 021252Z ASCATC IMAGE SHOWS A BROAD CIRCULATION HAS FORMED BELOW
THE PERSISTENT CONVECTION ADJACENT TO A SWATH OF 25-30 KNOT GRADIENT
WINDS ENVIRONMENTAL ANALYSIS REVEALS A MARGINAL FAVORABLE ENVIRONMENT
FOR DEVELOPMENT WITH LOW TO MODERATE VERTICAL WIND SHEAR (VWS) OF 15-20
KNOTS, DUAL-CHANNEL UPPER-LEVEL OUTFLOW, AND WARM SEA SURFACE
TEMPERATURES (SST) OF 29-30 C. DETERMINISTIC MODELS INDICATE A CLOSED
CIRCULATION FORMING ADJACENT TO A SWATH OF 25-30 KNOT GRADIENT WINDS
OVER THE NEXT 24-36 HOURS, WITH SLOW INTENSIFICATION AND A NORTHWARD
TRACK TOWARD WESTERN JAPAN. THE GEFS AND ECENS ENSEMBLES ALSO SUPPORT A
NORTHWARD TRACK TOWARD KYUSHU OVER THE NEXT TWO DAYS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 20 TO 25 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
031500Z.//
NNNN

TD a
Issued at 2025/09/02 13:25 UTC
Analysis at 09/02 12 UTC
Grade TD
Scale -
Intensity -
Center position N21°30′ (21.5°)
E133°35′ (133.6°)
Direction and speed of movement N 20 km/h (10 kt)
Central pressure 1006 hPa
Maximum sustained wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)

[Hayabusa]

21W TWENTYONE 250903 1200 27.0N 131.6E WPAC 30 1002

[Hayabusa]

T2515(Peipah)
Issued at 2025/09/03 18:55 UTC
Analysis at 09/03 18 UTC
Grade TS
Scale -
Intensity -
Center position N28°10′ (28.2°)
E130°55′ (130.9°)
Direction and speed of movement N 30 km/h (15 kt)
Central pressure 1002 hPa
Maximum sustained wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of 30-kt wind area 280 km (150 NM)