NATL: HUMBERTO - Remnants - Discussion

[TallyTracker]

Insane microwave images for Humberto:

https://i.ibb.co/Y7LrWcc0/08-L-89-H-20250927165455.webp
https://i.ibb.co/FLBn86hc/2221692.webp
https://i.ibb.co/DD617gN2/08-L-color37-20250927165455.webp

That is rare form for an Atlantic hurricane. I’d be stunned if this is not a Cat 5 and likely more than borderline at that.

[MarioProtVI]

AL, 08, 2025092718, , BEST, 0, 228N, 608W, 135, 926, HU

Fingers crossed they go 5 kt higher for the official advisory like they did several times Thursday and Friday. Although they tend to do that earlier in a system’s life or during initial RI bursts.

Highly doubt so as I’m already starting to see signs of an EWRC kicking in on IR. They’re not gonna upgrade it until it gets a SAB/ADT 7.0 which it very likely won’t.

[Beef Stew]

Eye temp is still over 20°C and there are no signs of deterioration / another EWRC at this point. It's possible that if the upward trend in objective estimates holds for a couple more hours, they'll have what they need to make the call at 21z. As a layperson, this seems at the very least close to Erin's presentation at her peak intensity, but I suppose it makes sense to be a little more conservative in the absence of recon data.

It's very rare for NHC to upgrade to a cat 5 without Recon. I know they famously did for Lorenzo in 2019, but before then Isabel in 2003 was the last time they did.

This is why I was so surprised earlier when they explicitly forecast a 140 kt peak given the lack of recon that would be in the storm. I thought they may be setting the stage to justify an upgrade to cat 5 based on satellite, but then they backed back down to a 135 kt peak in the last advisory (which is also confusing to me), so I feel like they won’t be going any higher than that operationally.

[zhukm29]

TAFB just came in at 140kts:
https://ftp.nhc.noaa.gov/atcf/fix/fal082025.dat

AL, 08, 202509271800, 10, DVTS, CI, , 2280N, 6060W, , 1, 140, 2, 921, 2, DVRK, , , , , , , , , , , , , , L, TAFB, SK, VI, 1, 7070 /////, , , GOES19, CSC, T,

[WaveBreaking]

I think an EWRC is starting to happen based on the slight trochoidal eye motion, the shrinking eye, and even the CDO getting cooler. Usually the CDO gets warmer before an EWRC, but I think this might a case like Erin and Milton where the outer eyewall starts throwing up very deep convection before the inner eyewall dissipates.

[Kingarabian]

T6.5 fix from SAB, somehow that W ring wasn't thick enough.

TXNT23 KNES 271822
TCSNTL

A. 08L (HUMBERTO)

B. 27/1800Z

C. 22.7N

D. 60.7W

E. ONE/GOES-E

F. T6.5/6.5

G. IR/EIR/VIS

H. REMARKS...MWG EYE SURROUNDED BY W AND EMBEDDED IN B RESULTS IN A DT
OF 6.5. THE MET IS 6.5 BASED ON A RAPIDLY DEVELOPING 24 HOUR TREND. THE
PT IS 6.5. THE FT IS BASED ON THE DT.

I. ADDL POSITIONS

NIL


...MONAGHAN

I've seen some outrageous SAB fixes but this one makes sense. Its unfortunately not a clear cut 7.0 on the Dvorak scale.

[StormWeather]

TAFB just came in at 140kts:
https://ftp.nhc.noaa.gov/atcf/fix/fal082025.dat

AL, 08, 202509271800, 10, DVTS, CI, , 2280N, 6060W, , 1, 140, 2, 921, 2, DVRK, , , , , , , , , , , , , , L, TAFB, SK, VI, 1, 7070 /////, , , GOES19, CSC, T,

So what does this mean? Is there a higher chance of seeing the NHC go for the 5?

[Yellow Evan]

SAB did not fix this correctly by all accounts. W ring was >.5 degrees even if a spec of B appeared on the north.

[Kingarabian]

TAFB just came in at 140kts:
https://ftp.nhc.noaa.gov/atcf/fix/fal082025.dat

AL, 08, 202509271800, 10, DVTS, CI, , 2280N, 6060W, , 1, 140, 2, 921, 2, DVRK, , , , , , , , , , , , , , L, TAFB, SK, VI, 1, 7070 /////, , , GOES19, CSC, T,

So what does this mean? Is there a higher chance of seeing the NHC go for the 5?

The blend of SAB/ADT/TAFB CURRENTLY support a blend of 135kts. If ADT can get up to 7.0 by 5pm they will likely pull the trigger. Even if ADT stays at 6.8 or lower they may pull the trigger at 5 pm because the most recent microwave pass was really impressive, and that depiction is only associated with upper echelon hurricanes.

[Teban54]

[bob rulz]

This is a cat 5 if I've ever seen one.

[ScottNAtlanta]

https://i.postimg.cc/bwRwjG45/goes19-vis-g19meso2small-0927-1909z.gif

Beautiful example of the stadium effect

[aspen]

T6.5 fix from SAB, somehow that W ring wasn't thick enough.

TXNT23 KNES 271822
TCSNTL

A. 08L (HUMBERTO)

B. 27/1800Z

C. 22.7N

D. 60.7W

E. ONE/GOES-E

F. T6.5/6.5

G. IR/EIR/VIS

H. REMARKS...MWG EYE SURROUNDED BY W AND EMBEDDED IN B RESULTS IN A DT
OF 6.5. THE MET IS 6.5 BASED ON A RAPIDLY DEVELOPING 24 HOUR TREND. THE
PT IS 6.5. THE FT IS BASED ON THE DT.

I. ADDL POSITIONS

NIL


...MONAGHAN

I've seen some outrageous SAB fixes but this one makes sense. Its unfortunately not a clear cut 7.0 on the Dvorak scale.

I’m curious, why does this fall just below a clear-cut 7.0?

[Ubuntwo]

Knew they were going to go with T6.5.

Sometimes I wonder if they’re even looking at the same imagery as we are (I know that ADT’s Dvorak imagery is slightly different than on TT for some reason).

I've seen some outrageous SAB fixes but this one makes sense. Its unfortunately not a clear cut 7.0 on the Dvorak scale.

I’m curious, why does this fall just below a clear-cut 7.0?

The 18z frame had several blips in the W ring on the north side, which subjectively could prevent the eye from being truly "embedded in W". This was a case of bad timing, as prior to and especially after that frame, the break filled in.

[Teban54]

Recent frames are looking more plausibly like an EWRC.

[Yellow Evan]

I've seen some outrageous SAB fixes but this one makes sense. Its unfortunately not a clear cut 7.0 on the Dvorak scale.

I’m curious, why does this fall just below a clear-cut 7.0?

The 18z frame had several blips in the W ring on the north side, which subjectively could prevent the eye from being truly "embedded in W". This was a case of bad timing, as prior to and especially after that frame, the break filled in.

Even with the B spec (which probably wouldn’t show up on 4 km imagery), the W ring was still greater than .5 degrees though.

[zhukm29]

Some images for posterity:

[zzzh]

Some images for posterity:

https://i.ibb.co/xtDfStLw/VIS202509271708.webp
https://i.ibb.co/pvH6rTZ5/IR-OTT202509271708.webp
https://i.ibb.co/35Qfwk7K/IR-BD202509271708.webp

What is the eye temp?

[StormWeather]

T#6.7 now

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

----- Current Analysis -----
Date : 27 SEP 2025 Time : 191019 UTC
Lat : 22:45:00 N Lon : 60:51:36 W


CI# /Pressure/ Vmax
6.7 / 931.0mb/132.2kt


Final T# Adj T# Raw T#
6.7 6.7 6.7

Estimated radius of max. wind based on IR : 17 km

Center Temp : +19.9C Cloud Region Temp : -70.7C

Scene Type : EYE

Subtropical Adjustment : OFF

Extratropical Adjustment : OFF

Positioning Method : ARCHER POSITIONING

Ocean Basin : ATLANTIC
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 : 97nmi
- Environmental MSLP : 1011mb

Satellite Name : GOES19
Satellite Viewing Angle : 31.1 degrees

[zhukm29]

Some images for posterity:

https://i.ibb.co/xtDfStLw/VIS202509271708.webp
https://i.ibb.co/pvH6rTZ5/IR-OTT202509271708.webp
https://i.ibb.co/35Qfwk7K/IR-BD202509271708.webp

What is the eye temp?

24.62°C