WPAC: SAOLA - Post-Tropical

[Hayabusa]

91W.INVEST

WP, 91, 2023082200, , BEST, 0, 185N, 1275E, 15, 0, DB, 0, , 0, 0, 0, 0, 0, 0, 0, 0, 0, W, 0, , 0, 0, INVEST, ,

91W INVEST 230822 0000 18.5N 127.5E WPAC 15 0

[Hayabusa]

[Hayabusa]

Euro operational 00z finally develops it

[Hayabusa]

EPS 00z

[Hayabusa]

WWJP27 ‎RJTD ‎220600
WARNING ‎AND ‎SUMMARY ‎220600.
WARNING ‎VALID ‎230600.
WARNING ‎IS ‎UPDATED ‎EVERY ‎6 ‎HOURS.
TROPICAL ‎DEPRESSION ‎1006 ‎HPA ‎AT ‎19N ‎127E ‎NNW ‎SLOWLY.

[doomhaMwx]

This appears to be organizing fast. Earlier ASCAT didn't find an LLCC but more recent MW suggests one could be forming underneath the robust MLC.




Latest Euro ensemble has good amount of typhoon-intensity members, a huge contrast from 12Z which had nothing!

[Hayabusa]

Eps 06z

[doomhaMwx]

Latest HY-2 pass shows that 91W's LLCC is partially exposed with 20kt winds occurring west of it, under the deep convection. A nearby ship (ID: DUUBLZG) also reported 1004.6 mb MSLP at 07Z. 91W is close to becoming a TC although convection has weakened in the last few hours.

[Hayabusa]

Up to medium

ABPW10 PGTW 222000
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/222000Z-230600ZAUG2023//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION (INVEST 90W) PREVIOUSLY LOCATED NEAR
19.4N 153.1E IS NOW LOCATED NEAR 18.0N 151.5E, APPROXIMATELY 482 NM
NORTHEAST OF GUAM. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY AND A
220730Z SSMIS 91GHZ MICROWAVE IMAGE DEPICT A WEAK, FULLY EXPOSED, AND
RAGGED LOW LEVEL CIRCULATION (LLC) WITH FLARING CONVECTION THAT IS
OFFSET EASTWARD. FORMATIVE, ALBEIT FRAGMENTED, BANDING IS ALSO FLARING
TO THE SOUTH. SCATTEROMETER DATA FROM A 220830Z PASS SHOWS 20-KNOT
WIND BARBS 40-NM TO THE NORTH AND EAST OF THE LLC. ANALYSIS SHOWS THAT
INVEST 90W IS IN A MARGINALLY FAVORABLE ENVIRONMENT WITH STRONG
POLEWARD OUTFLOW AND WARM (30C) SEA SURFACE TEMPERATURES OFFSET BY
MODERATE TO STRONG (15-20 KNOT) RELATIVE VERTICAL WIND SHEAR AND
SUBSIDENCE ALONG THE NORTHERN PERIPHERY CAUSED BY A MID-LATITUDE
TROUGH. GLOBAL MODELS AGREE THAT 90W WILL DRIFT TO WEST-SOUTHWESTWARD
OVER THE NEXT 24 HOURS WITH GRADUAL DEVELOPMENT THEN TURN MORE
NORTHWARD AFTER TAU 36. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED
AT 17 TO 23 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 HIGH. SEE REF A
(WTPN21 PGTW 221400) FOR FURTHER DETAILS.
(2) THE AREA OF CONVECTION (INVEST 91W) PREVIOUSLY LOCATED NEAR
19.2N 128.1E IS NOW LOCATED NEAR 19.0N 126.9E, APPROXIMATELY 435 NM
SOUTH OF KADENA AB OKINAWA, JAPAN. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS PERSISTENT DEEP CONVECTION WITH STRONG MID-
LEVEL TURNING. A 221727Z ATMS 88.2GHZ PASS INDICATES THE LOW LEVEL
CIRCULATION CENTER IS POSITIONED ON THE NORTHEAST EDGE OF A WEAK
CURVED BAND OF DEEP CONVECTION WITH THE BULK OF THE DEEP CONVECTION
CONFINED TO THE SOUTHWEST QUADRANT. ENVIRONMENTAL ANALYSIS INDICATES
MARGINALLY FAVORABLE CONDITIONS FOR DEVELOPMENT WITH WARM (29-30C) SST
AND LOW VERTICAL WIND SHEAR (10-15 KTS) OFFSET BY WEAK OUTFLOW ALOFT
AND THE PRESENCE OF DRY AIR. GLOBAL MODELS SHOW A STEADY NORTHWARD
TRACK WITH SLOW DEVELOPMENT 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.

[Hayabusa]

Euro 12z lots of intense ensembles, operational peaks at ~940mb, strongest ensemble 915mb

[doomhaMwx]

TCFA

WTPN21 PGTW 230230

THE AREA OF CONVECTION (INVEST 91W) PREVIOUSLY LOCATED NEAR
19.0N 126.9E IS NOW LOCATED NEAR 19.1N 126.4E, APPROXIMATELY 442 NM
SOUTH OF KADENA AB, OKINAWA, JAPAN. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY AND A 222146Z SSMIS 91GHZ PASS DEPICT A CONSOLIDATING LLCC WITH
DEEP CONVECTION BUILDING OVER THE CENTER AND FORMATIVE BANDING IN THE
SOUTHWEST QUADRANT. ENVIRONMENTAL ANALYSIS INDICATES GENERALLY FAVORABLE
CONDITIONS FOR DEVELOPMENT WITH WARM (29-30C) SST, LOW VERTICAL WIND
SHEAR (5-10 KTS), AND GOOD OUTFLOW ALOFT. GLOBAL MODELS SHOW A STEADY
NORTHWARD TRACK WITH GRADUAL DEVELOPMENT OVER THE NEXT 48 HOURS.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 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.

[Hayabusa]

Eps 18z

[Hayabusa]

Euro 00z intense typhoon traversing the Luzon strait

[Hayabusa]

Euro 00z peaks it 927 mb... peak ensemble 907 mb

[doomhaMwx]

Most probably a TC now. It's even more organized than what JTWC classified as 08W east of the Marianas earlier today.

[doomhaMwx]

06Z GFS now develops 91W into an intense typhoon as well.

[Hayabusa]

EPS 06Z

[ElectricStorm]

Latest HWRF down to 944mb at the end up the run

[doomhaMwx]

Most probably a TC now. It's even more organized than what JTWC classified as 08W east of the Marianas earlier today.

The latest ASCAT pass confirms 91W is now a tropical depression and 30kts at that. With this data, an upgrade from JTWC should be coming at 18Z.

[Hayabusa]

09W NINE 230823 1800 19.6N 125.3E WPAC 25 1001