WPAC: INVEST 92W

[Hayabusa]

92W INVEST 250729 1800 34.2N 151.4E WPAC 15 0

[Hayabusa]

ABPW10 PGTW 300130
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/300130Z-300600ZJUL2025//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/291952ZJUL2025//
REF/B/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/291951ZJUL2025//
NARR/REFS A AND B ARE TROPICAL CYCLONE WARNINGS.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 29JUL25 1800Z, TROPICAL STORM 12W (KROSA) WAS LOCATED
NEAR 28.7N 142.8E, APPROXIMATELY 426 NM SOUTH-SOUTHEAST OF YOKOSUKA,
JAPAN, AND HAD TRACKED NORTHWARD AT 01 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 40 KNOTS GUSTING TO
50 KNOTS. SEE REF A (WTPN31 PGTW 292100) FOR FURTHER DETAILS.
(2) AT 29JUL25 1800Z, TROPICAL STORM 11W (CO-MAY) WAS LOCATED
NEAR 29.3N 122.9E, APPROXIMATELY 135 NM SOUTH-SOUTHEAST OF SHANGHAI,
CHINA, AND HAD TRACKED NORTH- NORTHWESTWARD AT 09 KNOTS OVER THE PAST
SIX HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 40 KNOTS
GUSTING TO 50 KNOTS. SEE REF B (WTPN33 PGTW 292100) FOR FURTHER
DETAILS.
(3) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
C. SUBTROPICAL SYSTEM SUMMARY:
(1) AN AREA OF CONVECTION (INVEST 92W) HAS PERSISTED NEAR 34.2N
151.4E, APPROXIMATELY 579 NM EAST OF TOKYO, JAPAN. THE SYSTEM IS
CURRENTLY CLASSIFIED AS A SUBTROPICAL CYCLONE, GENERALLY CHARACTERIZED
AS HAVING BOTH TROPICAL AND MIDLATITUDE CYCLONE FEATURES. ANIMATED
INHANCED INFRARED SATELLITE IMAGERY DEPICTS A WEAK LLCC ON THE
SOUTHEASTERN FLANK OF AN UPPER-LEVEL TROUGH, CURRENTLY FULLY EXPOSED
AND BEING SHEARED FROM THE NORTHWEST, WITH A DEEP CONVECTIVE CLOUD
SYSTEM ON THE SOUTHEAST SIDE. ENVIRONMENTAL ANALYSIS REVEALS
UNFAVORABLE CONDITIONS FOR TROPICAL TRANSITION DEFINED BY A DEEP LAYER
OF DRY AIR BEING ADVECTED OVER THE LOW LEVEL CIRCULATION AND HIGH (30
KNOTS) WESTERLY VERTICAL WIND SHEAR ASSOCIATED WITH AN APPROACHING
LONGWAVE TROUGH. FURTHERMORE, THE SYSTEM IS FAST APPROACHING WATERS
NOT CONDUCIVE FOR TROPICAL DEVELOPMENT (COOLER THAN 26C). GLOBAL
DETERMINISTIC MODELS ARE IN AGREEMENT ON A NORTHEASTWARD TRACK WITH AN
ASYMMETRIC WIND FIELD OVER THE NEXT 24 TO 48 HOURS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 25 TO 30 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 SUBTROPICAL SYSTEMS.
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 SUBTROPICAL LOW TO PARA 1.C.(1).
//
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