WPAC: SAOLA - Post-Tropical

[xtyphooncyclonex]

Ready for takeoff.

[mrbagyo]

EWRC ongoing

[underthwx]

EWRC ongoing

https://i.imgur.com/lU84kLl.jpg

Looks like extreme Northeastern Luzon got a bit of rainfall from Goring?

[cycloneye]

09W SAOLA 230828 1800 18.3N 123.9E WPAC 100 953

[doomhaMwx]

As Saola has been deviating west of the forecast tracks and models have also been significantly trending south, an eye/eyewall passage is now looking likely for both the Babuyan and Batanes Islands in the next ~24 hours.

[Hayabusa]

Back to cat 4 and it's now looking pretty good

09W SAOLA 230829 0600 18.9N 123.1E WPAC 120 935

[xtyphooncyclonex]

Grays popping on AVN surrounding a quickly warming eye... oh boy

[doomhaMwx]

Won't be shocked if we see a category 5 in the coming hours.

[aspen]

Very impressive recovery over the last 6-12 hours. This is one of the most symmetrical CDOs I can recall in a WPac system. Once the eye hits WMG, it’s an easy 150-160 kt Cat 5 super.

[xtyphooncyclonex]

ADT starting to skyrocket.

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 9.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 29 AUG 2023 Time : 113000 UTC
Lat : 19:13:47 N Lon : 122:46:47 E


CI# /Pressure/ Vmax
6.5 / 930.3mb/127.0kt


Final T# Adj T# Raw T#
6.5 6.8 6.8

Estimated radius of max. wind based on IR : 22 km

Center Temp : +12.5C Cloud Region Temp : -74.9C

Scene Type : EYE

Subtropical Adjustment : OFF

Extratropical Adjustment : OFF

Positioning Method : ARCHER POSITIONING

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 88nmi
- Environmental MSLP : 1004mb

Satellite Name : HIM-9
Satellite Viewing Angle : 30.4 degrees

[Goomba]

Saola's current structure and location somewhat remind me of Cimaron in 2006, except Cimaron had a CDG ring and it hit Luzon.

[Foxfires]

Wow this thing exploded.

[Hayabusa]

Almost cat 5

09W SAOLA 230829 1200 19.3N 122.7E WPAC 135 922

[cycloneye]

SuperTyhoon.

09W SAOLA 230829 1200 19.3N 122.7E WPAC 135 922

[Sciencerocks]

 https://twitter.com/VortixWx/status/1696512792570789943

[cycloneye]

WDPN32 PGTW 291500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 09W (SAOLA) WARNING NR
024//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 19.3N 122.7E
INITIAL INTENSITY: 135 KTS
GEOGRAPHIC REFERENCE: 298 NM NORTH-NORTHEAST OF MANILA,
PHILIPPINES
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 06 KTS
SIGNIFICANT WAVE HEIGHT: 46 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
SUPER TYPHOON (STY) 09W (SAOLA) HAS LITERALLY EXPLODED OVER THE
PAST 12 HOURS, GOING FROM A MODERATE TYPHOON WITHOUT AN EYE, TO A
135 KNOT STY WITH A 21NM WIDE STADIUM EYE. EYE TEMPERATURES ARE NOW
AN AMAZING +16C, FAR EXCEEDING THE MAGICAL WARM MEDIUM GRAY
THRESHOLD IN THE IRBD IMAGERY. UNFORTUNATELY, THE PHILIPPINE RADAR
NETWORK OVER NORTHEASTERN LUZON APPEARS TO BE DOWN, BUT REGARDLESS,
THE LARGE STADIUM EYE IN THE ENHANCED INFRARED (EIR) IMAGERY AND A
290921Z SSMIS 91GHZ MICROWAVE IMAGE SHOW A VERY WELL-ORGANIZED
SYSTEM, WITH A SINGULAR WIDE BAND OF CONVECTION COMPLETELY
SURROUNDING THE EYE FEATURE. THE INITIAL POSITION IS ASSESSED WITH
HIGH CONFIDENCE BASED ON THE EYE IN THE EIR AND AN EXTRAPOLATION OF
THE MICROWAVE EYE. THE INITIAL INTENSITY IS ASSESSED WITH HIGH
CONFIDENCE BASED ON AN OVERALL ASSESSMENT OF THE AGENCY CURRENT
INTENSITY ESTIMATES OF T6.5 TO T7.0 AND SUBJECTIVE INTENSITY
ESTIMATES BETWEEN 122-132 KNOTS. THE SYSTEM IS MOVING NORTHWEST
ALONG THE SOUTHWESTERN EDGE OF A DEEP SUBTROPICAL RIDGE (STR) TO
THE NORTHEAST. CLEARLY, THE ENVIRONMENT IS CONDUCIVE TO RAPID
INTENSIFICATION, WITH ZESTY SSTS WHICH HAVE RECOVERED FROM THE WEAK
UPWELLING INDUCED BY TRAVERSE OF STY 09W THROUGH THIS SAME REGION
FOUR DAYS AGO. OUTFLOW IS RADIAL BUT RELATIVELY CONFINED TO THE
REGION AROUND THE STORM ITSELF WITH NO CLEAR OUTFLOW CHANNELS.
CIMSS ANALYSIS INDICATES 21 KNOTS OF EASTERLY SHEAR, WHICH MAY IN
FACT BE PRESENT, BUT ANALYSIS OF EARLIER WATER VAPOR IMAGERY SHOWS
AN OUTFLOW ARC EXTENDING EASTWARD AND A SUBSIDENT AREA EAST OF
THAT; A CLASSICAL SETUP FOR RI IN A MODERATE EASTERLY SHEAR
ENVIRONMENT, WHICH OCCURRED IN VERY RAPID SUCCESSION TO THE ACTUAL
ONSET OF THE RI.

INITIAL WIND RADII BASIS: PERSISTENCE

CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) TO THE NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T7.0 - 140 KTS
RJTD: T6.5 - 127 KTS
RCTP: T7.0 - 140 KTS
KNES: T6.5 - 127 KTS
CIMSS ADT: 127 KTS AT 291130Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE
VWS: 15-20 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL

ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING, OTHER THAN THE RAPID
INCREASE IN THE INITIAL INTENSITY.

FORECAST DISCUSSION: STY 09W HAS EXCEEDED ALL EXPECTATIONS, AND
UNDERGONE EXTREME RAPID INTENSIFICATION, EXPLODING FROM NEAR 100
KNOTS AT 290000Z TO 135 KNOTS 12 HOURS LATER. AS THE SYSTEM
TRAVERSES THE NORTHERN BABUYAN ISLANDS OVER THE NEXT 12 HOURS, IT
IS LIKELY TO INTENSIFY ANOTHER FEW KNOTS, WITH THE FORECAST PEAKING
OUT AT 140 KNOTS BY TAU 12. THE SYSTEM WILL THEN CONTINUE TRACKING
WEST-NORTHWEST INTO THE NORTHERN PORTION OF THE SOUTH CHINA SEA
(SCS) THROUGH TAU 48, PASSING WELL SOUTH OF TAIWAN ON ITS WAY
TOWARDS THE CHINESE COAST UNDER THE STEERING INFLUENCE OF THE STR
CENTERED FAR TO THE NORTHEAST. AROUND TAU 48, A RELATIVELY DEEP
MID-LATITUDE TROUGH WILL PASS BY TO THE NORTH, BUT WILL REMAIN FAR
ENOUGH TO THE NORTH TO NOT INFLUENCE THE TRACK OF STY 09W ALL THAT
MUCH. THE TRANSIENT ANTICYCLONE THAT DEVELOPS IN THE WAKE OF THIS
TROUGH, HOWEVER WILL HAVE AN IMPACT, TURNING THE SYSTEM ONTO A MORE
WESTWARD TRACK BY AFTER TAU 48. THE TRANSIENT ANTICYCLONE QUICKLY
MOVES NORTHEAST AND IS ABSORBED INTO THE LARGER STR COMPLEX, BUT
LEAVES BEHIND A SHARP RIDGE WHICH EXTENDS ALL THE WAY FROM SOUTHERN
CHINA TO 40N 160E. THIS RIDGE PATTERN WILL SERVE TO PUSH STY 09W
ONTO A WEST-SOUTHWEST TRACK FROM TAU 72 ONWARD, WITH THE TRACK
SKIRTING THE COAST NEAR HONG KONG BY TAU 96 THEN OPENING THE
DISTANCE TO THE COAST THEREAFTER. IN TERMS OF INTENSITY, AS
MENTIONED, THE SYSTEM IS FORECAST TO PEAK AT 140 KNOTS WITHIN THE
NEXT 12 HOURS. THE CIMSS M-PERC EYEWALL REPLACEMENT CYCLE (EWRC)
MODELS ARE STARTING TO RAMP UP AGAIN, WITH THE FULL-MODEL
PREDICTING A 30 PERCENT PROBABILITY OF EWRC WHILE THE VMAX-MODEL
SHOWING 60 PERCENT. WITH SUCH AN INTENSE SYSTEM UNDER THE INFLUENCE
OF MODERATE EASTERLY SHEAR, THE ONSET OF AN EWRC IS LIKELY WITHIN
THE NEXT 24 HOURS. HENCE THE SYSTEM IS FORECAST TO WEAKEN AS IT
TRACK SOUTHWEST OF TAIWAN, BUT THEN MAINTAIN INTENSITY AS IT TAPS
INTO A MODEST POLEWARD OUTFLOW CHANNEL AROUND TAU 48 WHICH SHOULD
HELP THE SYSTEM TO RECOVER FROM A POSSIBLE EWRC. BY TAU 72, THE
SYSTEM BEGINS TO FEEL THE EFFECTS TO COOLER WATERS, INGESTION OF
DRY CONTINENTAL AIR FROM MAINLAND CHINA AND AN INCREASE IN
MID-LEVEL SHEAR, MARKING THE BEGINNING OF A STEADY WEAKENING TREND
THAT CONTINUES THROUGH THE END OF THE FORECAST PERIOD.

MODEL DISCUSSION: DETERMINISTIC AND ENSEMBLE TRACK GUIDANCE HAS
COME INTO SLIGHTLY BETTER AGREEMENT WITH THE LATEST RUN. THE ECMWF
CONTINUES TO TRACK THE SYSTEM INTO CHINA IN THE VICINITY OF
SHANTAU, WHILE THE GFS CONTINUES TO TAKE A MORE SOUTHERN ROUTE.
HOWEVER, THE ECMWF IS NOW THE SOLE OUTLIER ON THE NORTHERN SIDE OF
THE ENVELOPE WHILE THE MAJORITY OF THE OTHER CONSENSUS MEMBERS HAVE
NOW JOINED THE GFS SIDE, PULLING THE SYSTEM FURTHER SOUTHWARD. THE
CONSENSUS AND THE JTWC FORECAST STILL LIE ON THE NORTHERN EDGE OF
THE TIGHTEST MODEL PACKING IN THE ENVELOPE. IN THE EXTENDED
FORECAST, THE GFS, NAVGEM AND GFS ENSEMBLE AS WELL AS THE CONSENSUS
MEAN SHOW THE SYSTEM BECOMING QUASI-STATIONARY OR TURNING SLOWLY
BACK TOWARDS THE EAST, LIKELY IN RESPONSE TO A FURTHER WESTWARD
TRACK OF TS 10W IN THE PHILIPPINE SEA. WHILE CONSIDERED UNLIKELY AT
THIS TIME, THIS SCENARIO WILL BEAR CLOSE SCRUTINY IN LATER MODEL
RUNS. INTENSITY GUIDANCE IS MIXED AND STRUGGLING TO CATCH UP TO THE
ERI, HOWEVER THE HAFS-A AND COAMPS-TC SUPPORT A GENERALLY FLAT
INTENSITY TREND THROUGH TAU 48 FOLLOWED BY RAPID WEAKENING AS THE
SYSTEM APPROACHES HONG KONG. THE JTWC FORECAST LIES CLOSE TO THE
HAFS-A GUIDANCE THROUGH THE BULK OF THE FORECAST PERIOD.

FORECAST CONFIDENCE:
TRACK 0 - 72 HR: HIGH
TRACK 72-120 HR: MEDIUM
INTENSITY 0 - 72 HR: MEDIUM
INTENSITY 72-120 HR: LOW//
NNNN

[mrbagyo]

JTWC - 135 knots (1-min)/ 922 hPa
CMA - Class 17, 60 m/s (about 216 km/h) - (2 min) / 920 hPa
JMA - 95 knots (10 min) / 940 hPa
PAGASA - 100 knots (10 min) / 935 hPa

[doomhaMwx]

The eye is now threading between Babuyan Island (population: ~2000) and the small, uninhabited Balintang Islands to the north. Extreme conditions are being experienced in these locations as we speak!

[cycloneye]

Very impressive SuperTyphoon.

[underthwx]

Very impressive SuperTyphoon.

https://i.imgur.com/VehhWsb.gif

Without a doubt CE