Time and Date in UTZ:

200600

/200600Z-210600ZSEP2024 /200152ZSEP2024 /200552ZSEP2024 NARR/REF A IS A . REF B IS A TROPICAL CYCLONE FORMATION ALERT

TYPHOON WARNINGS for East Asian and Western Pacific:

(180 TO MALAY PENINSULA):

Summary 1:

(1) AT 20SEP24 0000Z, TROPICAL DEPRESSION 15W (PULASAN) WAS LOCATED NEAR 32.0N 120.3E, APPROXIMATELY 78 NM NORTHWEST OF SHANGHAI, CHINA, AND HAD TRACKED NORTHWESTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SUSTAINED SURFACE WINDS WERE ESTIMATED AT 30 KNOTS GUSTING TO 40 KNOTS. SEE REF A (WTPN32 PGTW 200300) FOR FURTHER DETAILS. (2) NO OTHER TROPICAL CYCLONES.

Summary 2:

(1) THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED NEAR 21.2N 127.6E IS NOW LOCATED NEAR 21.7N 127.1E, APPROXIMATELY 368 NM EAST-SOUTHEAST OF TAIPEI, TAIWAN. ANIMATED VISIBLE SATELLITE IMAGERY DEPICTS EXPOSED LOW LEVEL CLOUD LINES WRAPPING INTO A DEFINED CIRCULATION CENTER. CONVECTION IS FLARING IN THE SOUTHERN QUADRANT WITH ANVILS SHEARED TO THE SOUTH. A PARTIAL SCATTEROMETRY PASS SHOWS THE SYSTEM IS FORMING ADJACENT TO AN EXTENSIVE BELT OF 20-30 KNOT SOUTHEASTERLY WINDS TO THE EAST OF THE CIRCULATION. DETERMINISTIC AND PROBABILISTIC MODELS DEPICT A DEEPENING SYSTEM FORMING BESIDE THE WIDE SWATH OF VIGOROUS LOW-LEVEL FLOW AND HEADING GENERALLY NORTHWESTWARD. GLOBAL MODELS INDICATE SLOW DEVELOPMENT; HOWEVER, THEY DO INDICATE A POSSIBILITY FOR THE STRONGER WINDS TO THE EAST TO WRAP AROUND THE CIRCULATION. ENVIRONMENTAL CONDITIONS ARE MARGINALLY FAVORABLE WITH MODERATE EQUATORWARD OUTFLOW ALOFT, MODERATE TO HIGH (20-25 KNOTS) VERTICAL WIND SHEAR AND WARM (30-31 C) SEA SURFACE TEMPERATURES CREATING A CONDUCIVE AREA FOR FURTHER DEVELOPMENT MOVING FORWARD. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO HIGH. SEE REF B (WTPN21 PGTW 200600) FOR FURTHER DETAILS. (2) NO OTHER SUSPECT AREAS.

Summary 3:

NONE.

TYPHOON WARNINGS for U.S West to East Pacific:

(WEST COAST OF SOUTH AMERICA TO 135 EAST):

Summary 1:

NONE.

Summary 2:

NONE.

Summary 3:

NONE