ATL: LEE - Post-Tropical - Discussion

[dukeblue219]

South Florida friend said local t v met just said that this storm not only will turn north but was specific in saying it would turn on Sunday morning, thus missing Florida.
Is that a valid statement this far out?

I'm inclined to blame the "friend said" for some of the miscommunication, but that would be an insanely overconfident statement for any met to make.

Sure, it's probably the case, but how it's communicated matters....

[Meteorcane]

Is a recurve definite?

A recurve is not definite unfortunately, it is the most probable solution given climatology and the longwave pattern, but whether this ends up as a threat to the Northeast US/Atlantic Canada will depend upon the pattern evolution in Day 7-10 which is not high confidence at this point (in addition Bermuda naturally will have to watch this carefully). As the NHC mentions, the northeastern Carib islands will have to watch the short-term motion of this system, as although the consensus would take it north lots of things can happen with an incipient disturbance that sometimes defies model predictions. I also wouldn't rule out direct impacts to the Turks and Caicos or maybe far eastern Bahamas.

For Florida and the SE CONUS the odds of any direct impacts is definitely quite low, as the combination of a weak subtropical ridge, combined with a longwave trough over the CONUS in the medium range (5-7 days) would favor at least a turn northward in that period. Whether that ends up as a full recurve NE or even a bend back NW toward the northeastern CONUS/Atlantic Canada is not certain as mentioned early.

[cycloneye]

Wow, the first time NHC has in a first advisory, the 120kt peak intensity.

 https://twitter.com/pppapin/status/1699101194088595703

[Emmett_Brown]

Is a recurve definite?

Most likely, it could be a safe recurve or it could be a problem for Atlantic Canada or Long Island/New England maybe even Bermuda so while I think it’s a definite recurve it could still be a dangerous hurricane for any of the above locations and before the recurve the northern lesser Antilles need to monitor this

Also worth pointing out that the official NHC forecast is the only forecast that matters, and it certainly does not show a recurve in the next 5 days.

[Michele B]

To our members in the Leeward Islands, please read this.

The depression is forecast to become a major hurricane by
this weekend and could bring impacts to the Leeward Islands by that
time. While it is too soon to determine the location and magnitude
of these possible impacts, interests in this area should monitor
the progress of the depression and updates to the forecast.

Today in 1995, Hurricane Luis hit us dead on.
Tomorrow in 2017, Hurricane Irma hit us dead on.
Incredible destruction from both storms.
To say that people here are watching and worrying about this storm, is an understatement.

"Hurricane Fatigue" is a real thing.

Those of us who have ever experienced a Cat 3 or higher storm know it.

I'm calling it a form of PTSD. We in FL are watching this one, too.

[Iceresistance]

Has a proto-eye, and it already looks like a Tropical Storm.


https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb

https://s11.gifyu.com/images/SgAER.gif

700 mb

https://s11.gifyu.com/images/SgAE6.gif

[underthwx]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

What is a "proto-eye"?...

[Iceresistance]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

What is a "proto-eye"?...

An eye-like feature.

Will need pro-mets to confirm it though

[TheBigO]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb
https://s11.gifyu.com/images/SgAER.gif
https://s11.gifyu.com/images/SgAER.gif

700 mb
https://s11.gifyu.com/images/SgAE6.gif
https://s11.gifyu.com/images/SgAE6.gif

The lower the MB number, the higher up in the atmosphere, right?

So 850 mb is like ~4800 ft and 700 mb is ~9900 feet, right?

[Iceresistance]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb
https://s11.gifyu.com/images/SgAER.gif
https://s11.gifyu.com/images/SgAER.gif

700 mb
https://s11.gifyu.com/images/SgAE6.gif
https://s11.gifyu.com/images/SgAE6.gif

The lower the MB number, the higher up in the atmosphere, right?

So 850 mb is like ~4800 ft and 700 mb is ~9900 feet, right?

Yes, the lower the number, the higher up in the atmosphere.

[Tireman4]

Waiting patiently on WXman57 to chime in

This is Mr. Wxman 57's Gardener. He told me to tell you all he is closely monitoring the situation and get with you in a short while. Meanwhile, back to mowing the yard on his palatial estate.

[KirbyDude25]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb
https://s11.gifyu.com/images/SgAER.gif
https://s11.gifyu.com/images/SgAER.gif

700 mb
https://s11.gifyu.com/images/SgAE6.gif
https://s11.gifyu.com/images/SgAE6.gif

Looking at the vorticity maps on UW-CIMSS, looks like TD13 is stacked all the way from 925 mb to 500 mb, which bodes very well for its future intensification

[cycloneye]

The big ones bloosom with this configuration.

 https://twitter.com/AndyHazelton/status/1699124308931641554

[blueskies]

Thank you all for posting the official NHC forecasts. And your analyses.
Question….does NHC email these forecasts? I remember I used to be on a mailing list for them. Is this still available?

You could try adding the NHC 7 Day Outlook for the Atlantic to your home screen. Do a search on the internet using the terms "NHC 7 day outlook". There is also a two day outlook.

The outlooks are updated at 8 am, 2 pm, 8 pm and 2 am.

[DorkyMcDorkface]

Hello there, Lee:

AL, 13, 2023090518, , BEST, 0, 129N, 411W, 35, 1006, TS

[cycloneye]

TXNT22 KNES 051829
TCSNTL

A. 13L (NONAME)

B. 05/1800Z

C. 12.9N

D. 41.4W

E. THREE/GOES-E

F. T2.5/2.5

G. IR/EIR/VIS

H. REMARKS...5/10 BANDING RESULTED IN A DT OF 2.5. MET AND PT AGREE. THE
FT IS BASED ON THE DT.

I. ADDL POSITIONS

NIL


...ZHU

[SconnieCane]

Should be noted the northern Leeward Islands are in the initial cone; although it would take a lot of left outliers verifying to bring the core over them, NHC rightly mentions potential for some level of impacts there in the first advisory.

[InfernoFlameCat]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb
https://s11.gifyu.com/images/SgAER.gif
https://s11.gifyu.com/images/SgAER.gif

700 mb
https://s11.gifyu.com/images/SgAE6.gif
https://s11.gifyu.com/images/SgAE6.gif

The lower the MB number, the higher up in the atmosphere, right?

So 850 mb is like ~4800 ft and 700 mb is ~9900 feet, right?

Kind of. The more intense the storm, the lower the height the mb is. For example, typhoon tips 850mb was only a few hundred feet above the surface.

[Iceresistance]

Has a proto-eye, and it already looks like a Tropical Storm.

https://s11.gifyu.com/images/SgAEh.gif
https://s11.gifyu.com/images/SgAEh.gif

And it is stacked already to 700 mb, which is very impressive for a TD

850 mb
https://s11.gifyu.com/images/SgAER.gif
https://s11.gifyu.com/images/SgAER.gif

700 mb
https://s11.gifyu.com/images/SgAE6.gif
https://s11.gifyu.com/images/SgAE6.gif

The lower the MB number, the higher up in the atmosphere, right?

So 850 mb is like ~4800 ft and 700 mb is ~9900 feet, right?

Kind of. The more intense the storm, the lower the height the mb is. For example, typhoon tips 850mb was only a few hundred feet above the surface.

Well, this is different, this is the atmospheric height level.

[Iceresistance]

It was at a 2.0 earlier today!

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

----- Current Analysis -----
Date : 05 SEP 2023 Time : 184020 UTC
Lat : 12:40:13 N Lon : 40:57:40 W


CI# /Pressure/ Vmax
2.3 /1010.3mb/ 33.0kt


Final T# Adj T# Raw T#
2.3 2.6 2.9

Center Temp : -42.7C Cloud Region Temp : -40.6C

Scene Type : CURVED BAND with 0.71 ARC in MD GRAY

Subtropical Adjustment : OFF

Extratropical Adjustment : OFF

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : 0.2T/hour
Weakening Flag : OFF
Rapid Dissipation Flag : OFF