WPAC: CHANTHU - Post-Tropical

[Yellow Evan]

The longer this pinhole lasts the stronger I think Chanthu is. It's ERC has yet to commence contrary to trends last night, evident of a stable structure, which is very rare for pinholes, and the overall satellite presentation has not changed substantially structure wise. More inclined to believe this has been a Category 5 hurricane for ~24 hours now.

[Subtrop]

TPPN11 PGTW 082100

A. SUPER TYPHOON 19W (CHANTHU)

B. 08/2030Z

C. 15.40N

D. 128.73E

E. ONE/HMWRI8

F. T7.0/7.0/D0.5/24HRS STT: D0.5/03HRS

G. IR/EIR

H. REMARKS: 05A/PBO IRREG EYE/ANMTN. OW EYE SURROUNDED BY W
YIELDS AN E# OF 6.0. ADDED 0.5 EYE ADJUSTMENT FOR CMG, TO YIELD
A DT OF 6.5. MET YIELDS A 7.0 AND PT YIELDS A 6.5. DBO MET.

I. ADDITIONAL POSITIONS:
08/1646Z 15.30N 129.23E AMS2
08/1656Z 15.22N 129.38E ATMS


BERMEA

[ElectricStorm]

New JTWC forecast now officially has Chanthu becoming a Cat 5 again, but it's probably already there, and it probably will peak at more than 140kts.

[Ntxw]

The longer this pinhole lasts the stronger I think Chanthu is. It's ERC has yet to commence contrary to trends last night, evident of a stable structure, which is very rare for pinholes, and the overall satellite presentation has not changed substantially structure wise. More inclined to believe this has been a Category 5 hurricane for ~24 hours now.

Once it goes poleward from the SW to W movement the outflow will be better. It's a classic cat 5 long track.

[Iceresistance]

The Inner Core of Chanthu is a perfect circle, literally!

[Yellow Evan]

TPPN11 PGTW 082100

A. SUPER TYPHOON 19W (CHANTHU)

B. 08/2030Z

C. 15.40N

D. 128.73E

E. ONE/HMWRI8

F. T7.0/7.0/D0.5/24HRS STT: D0.5/03HRS

G. IR/EIR

H. REMARKS: 05A/PBO IRREG EYE/ANMTN. OW EYE SURROUNDED BY W
YIELDS AN E# OF 6.0. ADDED 0.5 EYE ADJUSTMENT FOR CMG, TO YIELD
A DT OF 6.5. MET YIELDS A 7.0 AND PT YIELDS A 6.5. DBO MET.

I. ADDITIONAL POSITIONS:
08/1646Z 15.30N 129.23E AMS2
08/1656Z 15.22N 129.38E ATMS


BERMEA

Lol at both JTWC and SAB not relying on DT (not that I think it's a terrible call).

[Kingarabian]

How much of a difference it makes when you have a ridge to the north to force a WSW/W movement vs little ridging and NW movement (Larry).

[aspen]

Probably still a Cat 5 because the pinhole seems immune to EWRCs, although I still can’t help but remember Eta and wonder if maybe Chanthu also isn’t as intense as we’re thinking. SAR supported 150 kt this morning and it’s possible Chanthu is still 150 kt now, but it’s also possible it did weaken to 130-135 kt and has remained at that intensity due to limited outflow in the NW quad.

Also a friend on Discord keeps thinking this is named Chthulu lol.

[aspen]

[Yellow Evan]

Eta was over a colder tropopause so it’s cold top signature is not as impressive as one may think and honestly the storm is more symmetrical and organized than Eta ever was. Reasonable to believe Chanthu is 10 knots stronger than Eta.

[Yellow Evan]

The longer this pinhole lasts the stronger I think Chanthu is. It's ERC has yet to commence contrary to trends last night, evident of a stable structure, which is very rare for pinholes, and the overall satellite presentation has not changed substantially structure wise. More inclined to believe this has been a Category 5 hurricane for ~24 hours now.

Once it goes poleward from the SW to W movement the outflow will be better. It's a classic cat 5 long track.

Tbf this is moving way south of forecast likely because the ridge is being pumped up. We’re getting to the point where this crashes into Luzon.

[Yellow Evan]

ERC probably underway.

[ElectricStorm]

Eye is starting to wobble which can be a sign of an ERC. Maybe that outer eyewall will finally take over.

[Yellow Evan]

TPPN11 PGTW 090009

A. SUPER TYPHOON 19W (CHANTHU)

B. 08/2340Z

C. 15.46N

D. 128.12E

E. ONE/HMWRI8

F. T7.0/7.0/D1.0/24HRS STT: S0.0/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 07A/PBO IRREG EYE/ANMTN. OW EYE SURROUNDED BY W
YIELDS AN E# OF 6.0. ADDED 0.5 EYE ADJUSTMENT FOR CMG, TO YIELD
A DT OF 6.5. MET YIELDS A 7.0 AND PT YIELDS A 6.5. DBO MET.

I. ADDITIONAL POSITIONS:
08/2005Z 15.22N 128.88E SSMS


BERMEA

[Subtrop]

19W CHANTHU 210909 0000 15.5N 128.1E WPAC 140 925

TY2114(Chanthu)
Issued at 2021/09/09 00:45 UTC

Analisys at 09/09 00 UTC
Category TY
Scale -
Intensity Violent
Center Position N15°30′(15.5°)
E128°5′(128.1°)
Direction and speed of movement W 20km/h(10kt)
Central pressure 935hPa
Maximum wind speed near the center 55m/s(105kt)
Maximum wind gust speed 75m/s(150kt)
50-kt wind area WIDE85km(45NM)
30-kt wind area WIDE165km(90NM)

[ElectricStorm]

Eye is contracting, CDO warming, looks like ERC is finally taking place for real this time. Probably not a Cat 5 anymore but it certainly was earlier so it's nice to see JTWC go with 140kts. New track forecast has shifted east and has it landfalling in Taiwan again.

[mrbagyo]

[InfernoFlameCat]

Beautiful. Nice structure. Clearly undergoing EWRC. May still end up with a pinhole though.

[Ed_2001]

Operationals still jumping around and there is a huge spread on the ensembles. Has to be a major headache for forecasters with such a high potential for high impacts but still thus far little certainty.

[doomhaMwx]

Model track guidance has once again shifted back to the right/north. Today's 00Z set of global models now all have the storm passing E of Taiwan before entering the E China Sea — quite a difference from 24hrs ago (but timing/sharpness of poleward turn still vary).



This has also become reflected on the latest agency forecast tracks. Extreme Northern Luzon is not out of the woods yet though, especially the Batanes islands where an eyewall hit or even direct passage from the eye is possible late tomorrow or on Saturday!