ATL: LEE - Post-Tropical - Discussion

[cycloneye]

 https://twitter.com/TropicalTidbits/status/1699939104245555556

[aspen]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

Not seeing any signs in the recon data, nor in microwave passes from just 2 hours ago.

[Teban54]

https://twitter.com/TropicalTidbits/status/1699939104245555556

Don't forget that even the aggressive hurricane models only showed RI starting tonight, so Lee was 12 hours ahead of schedule.

[wx98]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

Not seeing any signs in the recon data, nor in microwave passes from just 2 hours ago.

The eye is quickly contracting on IR.

[GCANE]

Recon fix is slightly south and west of forecast track

[kronotsky]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

What does eye RH have to do with EWRC? It seems acausal to me that an early EWRC indicator would come from the absolute center of the system.

[BobHarlem]

 https://twitter.com/wxtrackercody/status/1699941739686142043

[GCANE]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

Not seeing any signs in the recon data, nor in microwave passes from just 2 hours ago.

This is the first signs, wont see it on recon flight level winds for a few hours if indeed an EWRC is starting.

[Blown Away]

the core of Lee and its damaging winds north of the Leeward Islands.
There is uncertainty in any northward turn of Lee beginning early
next week, but it is too soon to speculate about specific potential
impacts a week or more out.

Ok, models are overwhelmingly making a N turn well N of the NE Caribbean. The NHC cone hints a slight WNW bend at day 5. The uncertainty has to be will in turn N at 66W or 70W? Not sure what would make the NHC make that statement??

[Sciencerocks]

[Hypercane_Kyle]

Off-hand, the only storm that I can think of that blew up quite as quickly as Lee did was Maria.

[ElectricStorm]

AL, 13, 2023090800, , BEST, 0, 170N, 518W, 135, 933, HU,

[Cyclenall]

This is certainly a historic evening, like last. I was hoping both Lee and Jova would be CAT5s at the same time but no dice. I'm anticipating how fast Lee's pressure is dropping between passes and this contracting of the eye - a sign of a Jova-like eye coming? It would be strange for a ERC this fast in the middle of EI (Wilma's more precarious pinhole eye lasted longer which is far more unstable than Lee's core).

[GCANE]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

What does eye RH have to do with EWRC? It seems acausal to me that an early EWRC indicator would come from the absolute center of the system.

Check this paper
https://journals.ametsoc.org/view/journ ... 0349.1.xml

[WalterWhite]

AL, 13, 2023090800, , BEST, 0, 170N, 518W, 135, 933, HU,

This seems premature given that recon has not completed its mission yet.

[wx98]

AL, 13, 2023090800, , BEST, 0, 170N, 518W, 135, 933, HU,

This seems premature given that recon has not completed its mission yet.

Best track data is updated at 0z regardless of recon or not. It can be corrected later if needed.

[verruckt]

[url]https://i.postimg.cc/G3XM0cHM/4546-E463-FD0-A-4946-97-DB-CD52-F95-EDAAF.jpg [/url]

the core of Lee and its damaging winds north of the Leeward Islands.
There is uncertainty in any northward turn of Lee beginning early
next week, but it is too soon to speculate about specific potential
impacts a week or more out.

Ok, models are overwhelmingly making a N turn well N of the NE Caribbean. The NHC cone hints a slight WNW bend at day 5. The uncertainty has to be will in turn N at 66W or 70W? Not sure what would make the NHC make that statement??

Because models are still models, and the timeframe is a week away.

NOAA's own model (HAFS) shows a prolonged west run before it ends. It's just far too early to tell what's going to happen.

[kronotsky]

The eye drop showed 74% RH at 850mb.
It looks to be drying out,
If trend continues to show lower RH on subsequent eye drops, may be an indicator for an onset EWRC.
Look for mesovorts in the eye to confirm.

What does eye RH have to do with EWRC? It seems acausal to me that an early EWRC indicator would come from the absolute center of the system.

Check this paper
https://journals.ametsoc.org/view/journ ... 0349.1.xml

I think you're drawing the wrong conclusion from the paper. Strong tropical cyclones in general have warm and dry eyes, and the large majority of EWRCs take place in strong storms, so purely by the selection criteria you would expect a dry eye at the onset of the EWRC. Dry eyes are a sign of a healthy circulation that is disrupted by an EWRC, which is why the relative humidity increases by the end of the EWRC as in figure 2.

[GCANE]

Calculated probability of an EWRC has increased significantly

https://tropic.ssec.wisc.edu/real-time/ ... leERC.html

[dukeblue219]

AL, 13, 2023090800, , BEST, 0, 170N, 518W, 135, 933, HU,

This seems premature given that recon has not completed its mission yet.

It's just the facts as they exist on the hour. Nothing more, nothing less, and not an official advisory.