WPAC: JEBI - Post-Tropical

[WAcyclone]

Category 5 sunset

[NotoSans]

I am not in favor of the PGTW Dvorak analysis - there has not been any obvious banding feature on EIR.

[xtyphooncyclonex]

At this rate, 170 kts is already attainable. CDO is deepening. This could be our next Meranti. The ECMWF failed big time in terms of intensity. A few days ago, they predicted a weak system over the Northern Marianas. Got a solid category 5 instead. In contrast to last year and early this year, Jebi has ended up stronger than expected. Huge ACE coming.

[doomhaMwx]

STY Jebi at sunset
08-31-2018 8:20am UTC

http://agora.ex.nii.ac.jp/cgi-bin/iiif/ ... 0FD6565A35

[euro6208]

WDPN31 PGTW 310900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 25W (JEBI) WARNING NR
17//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUPER TYPHOON 25W (JEBI), LOCATED APPROXIMATELY 253 NM NORTHWEST
OF SAIPAN, HAS TRACKED WEST-NORTHWESTWARD AT 14 KNOTS OVER THE PAST
SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A
COMPACT SYSTEM, APPROXIMATELY 145NM DIAMETER CENTRAL DENSE
OVERCAST, WITH A 15NM ROUND EYE. THE INITIAL INTENSITY IS ASSESSED
AT 150 KNOTS,BETWEEN THE PGTW DVORAK CURRENT INTENSITY ESTIMATE OF
T7.5 (155 KNOTS), THE RJTD/KNES ESTIMATES OF T7.0 (140 KTS), AND A
310331Z SATCON ESTIMATE OF 142 KNOTS. A 310721Z GMI 36GHZ COLOR
COMPOSITE IMAGE INDICATES AN EYEWALL REPLACEMENT CYCLE IS ONGOING,
WITH TWO EYEWALLS PRESENT AND A MOAT OF SUBSIDENCE BETWEEN THEM.
UPPER-LEVEL ANALYSIS REVEALS A VERY FAVORABLE ENVIRONMENT WITH LOW
VERTICAL WIND SHEAR, RADIAL OUTFLOW ENHANCED BY A TUTT CELL TO THE
EAST, WARM SSTS (29-31 C) AND HIGH OCEAN HEAT CONTENT VALUES, THAT
HAVE PERMITTED STY 25W TO RAPIDLY INTENSIFY OVER THE PAST SEVERAL
DAYS. STY 25W IS TRACKING ALONG THE SOUTHERN PERIPHERY OF AN EAST-
WEST ORIENTED SUBTROPICAL RIDGE (STR).
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY FROM THE
PREVIOUS WARNING.
B. STY 25W WILL CONTINUE TO TRACK WESTWARD TO WEST-NORTHWESTWARD
THROUGH TAU 24 THEN WILL TURN NORTHWESTWARD TO NORTH-NORTHWESTWARD
ALONG THE WESTERN PERIPHERY OF THE STR THROUGH TAU 72. NUMERICAL
MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 72 WITH A SPREAD OF
235 NM AT TAU 72. BASED ON THE LOW UNCERTAINTY IN THE TRACK
GUIDANCE, CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST IS
HIGH. ENVIRONMENTAL CONDITIONS ARE FORECAST TO REMAIN VERY
FAVORABLE THROUGH TAU 48, THEREFORE, THE SYSTEM WILL MAINTAIN SUPER
TYPHOON INTENSITY UNTIL TAU 48. HOWEVER, DUE TO THE EYEWALL
REPLACEMENT CYCLE, SHORT-TERM INTENSITY FLUCTUATIONS ARE POSSIBLE,
AND THERE IS SOME UNCERTAINTY IN THE JTWC INTENSITY FORECAST
THROUGH TAU 72. ONCE THE PRIMARY EYEWALL IS STARVED OF INFLOW AND
DISSIPATES, INTENSITY IS EXPECTED TO WEAKEN SLIGHTLY, BUT THEN AS
THE SECONDARY EYEWALL DOMINATES, BECOMES THE NEW PRIMARY EYEWALL,
AND CONTRACTS, THE SYSTEM MAY INTENSIFY ONCE AGAIN.
C. AFTER TAU 72, STY 25W WILL ACCELERATE NORTHWARD TO NORTH-
NORTHEASTWARD TOWARD CENTRAL HONSHU AS IT ROUNDS THE STR AXIS. STY
25W WILL GRADUALLY WEAKEN AS A WARM-CORE TROPICAL SYSTEM BEFORE TAU
96 DUE TO AN INCREASINGLY UNFAVORABLE ENVIRONMENT WITH LOWER OCEAN
HEAT CONTENT AND HIGHER VERTICAL WIND SHEAR. STY 25W IS EXPECTED TO
BEGIN EXTRA-TROPICAL TRANSITION (ETT) BY TAU 96 AS IT BEGINS TO
INTERACT WITH A DEEP MIDLATITUDE SHORTWAVE TROUGH DIGGING INTO THE
KOREAN PENINSULA AND WESTERN JAPAN, WHICH WILL TEMPORARILY ENHANCE
OUTFLOW. STY 25W WILL RAPIDLY COMPLETE ETT AS IT BECOMES EMBEDDED
WITHIN THE MIDLATITUDE SHORTWAVE TROUGH AND GAINS FRONTAL
CHARACTERISTICS OVER THE SEA OF JAPAN. THE SYSTEM WILL RAPIDLY
WEAKEN AFTER TAU 96 DUE TO INCREASING VERTICAL WIND SHEAR, COLDER
SSTS IN THE SEA OF JAPAN, AND INCREASED FRICTIONAL EFFECTS FROM
JAPAN. AFTER COMPLETING ETT, THE OCCLUDING EXTRA-TROPICAL LOW IS
FORECAST TO MAINTAIN STORM-FORCE WINDS AND THE WIND FIELD IS
FORECAST TO BECOME MORE EXPANSIVE AND ASYMMETRIC AS IT TRACKS
POLEWARD. MODELS STILL DEPICT SOME VARIATION IN TIMING AND SPEED OF
THE RECURVE AFTER TAU 72. THEREFORE, THERE IS LOW CONFIDENCE IN
THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[1900hurricane]

I guess the flip side of every AMSU pass hitting yesterday is that none are today...

[euro6208]

What a monster

[euro6208]

CIMSS/NESDIS-USAF/NRL AMSU TC Intensity Estimation:
SUPER TYPHOON 25W
Thursday 30aug18 Time: 2241 UTC
Latitude: 17.85 Longitude: 144.68
Storm position corresponds to AMSU-A FOV 13 [1<--->30]
-----------------------------------------------------------------
| Estimated MSLP: 914 hPa
| Estimated Maximum Sustained Wind: 156 kts
| Estimate Confidence: Good ( +/- 10mb +/- 12kts )
-----------------------------------------------------------------
Storm is sub-sampled: Bias correction applied is -18.3 hPa
Channel 8 (~150 hPa) Tb Anomaly: 4.43
Channel 7 (~250 hPa) Tb Anomaly: 4.04
RMW: 9 km
RMW Source is: MW
Environmental Pressure: 1007
Satellite: NOAA-18
ATCF data for Month: 08 Day: 31 Time (UTC): 0000

For imagery, go to http://amsu.ssec.wisc.edu
For all comments and questions mailto:chrisv@ssec.wisc.edu

[doomhaMwx]

RGB satellite animation of STY Jebi from sunrise to sunset today.

(May take quite long to load due to large file size)

https://s1.gifyu.com/images/latest.gif

[Highteeld]

[Highteeld]

12z best track down to 910 mb, still 150 kts

[euro6208]

 https://twitter.com/anthonywx/status/1035497851881750528

[euro6208]

 https://twitter.com/EarthUncutTV/status/1035494386715394051

[mrbagyo]

The surge risk is real.

[euro6208]

Fourth straight 7.5...


TPPN10 PGTW 311221

A. SUPER TYPHOON 25W (JEBI)

B. 31/1150Z

C. 18.57N

D. 141.44E

E. ONE/HMWRI8

F. T7.5/7.5/D1.0/24HRS STT: S0.0/03HRS

G. IR/EIR

H. REMARKS: 01A/PBO EYE/ANMTN. WMG EYE SURROUNDED BY W YIELDS
AN E# OF 6.0. ADDED 1.0 FOR EYE ADJUSTMENT TO YIELD A DT OF
7.0, ADDED 0.5 FOR BF RESULTING IN DT OF 7.5. MET AND PT AGREE.
DBO DT.

I. ADDITIONAL POSITIONS:
31/0721Z 18.32N 142.45E GPMI
31/0832Z 18.30N 142.22E SSMS
31/0851Z 18.33N 142.18E WIND


VEERKAMP

[mrbagyo]

Going downhill.

[1900hurricane]

Looks like eyewall replacement. I don’t think this one will take too long though.

[Cunxi Huang]

Well looks like Jebi just completed one ERC. But recent 36ghz also suggest a strong rain band which could turn into an outer eyewall later on.

[cycloneye]

[mrbagyo]