ATL: LEE - Post-Tropical - Discussion

[ElectricStorm]

I don't like this one at all, could be a very impactful one down the road

[cycloneye]

This could be a long thread if it follows the modeling. These are the storms everyone looks for to make a season. Definitely would be watching this if I was in the Islands.

Watching very closely from PR. I am sure our friends in the Leewards and Virgin Islands are watching too and we have members from those islands.

[SFLcane]

If this gets into the Caribbean watch out..

[Sciencerocks]

[Craters]

Well, this one certainly has "that look." Dang it.

[Ianswfl]

If this gets into the Caribbean watch out..

You think it will get that far south??

[Iceresistance]

If this gets into the Caribbean watch out..

You think it will get that far south??

Irma 2017 kept diving SW, if she did it, then 95L (Eventually Lee) can do it.

[psyclone]

This could be the northeast caribbean threat that WXman has been warning us about. Probably a peak season long track whopper that ends up as a centerpiece of the season. The look, location, heading and calendar say watch out.

[ConvergenceZone]

Although this will probably be 90% likely to go out to sea away from the US mainland , based on position, climatology, and what the models are seeing, I think it's definitely a threat for the islands.

[kevin]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

[WalterWhite]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

There is a real chance 95L could become a Category V hurricane if it recurves out to sea. The MDR at record-warm temperatures.

[mantis83]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

There is a real chance 95L could become a Category V hurricane if it recurves out to sea. The MDR at record-warm temperatures.

or, if the 12z gfs is right, it will be nothing lol

[IcyTundra]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

There is a real chance 95L could become a Category V hurricane if it recurves out to sea. The MDR at record-warm temperatures.

or, if the 12z gfs is right, it will be nothing lol

Hard to trust the GFS with how inconsistent it is run to run. Will be interesting to see if the Euro trends weaker.

[Hypercane_Kyle]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

There is a real chance 95L could become a Category V hurricane if it recurves out to sea. The MDR at record-warm temperatures.

or, if the 12z gfs is right, it will be nothing lol

GFS struggling highly with genesis this year. It's been doing this dance with 95L for a few days now, whereas the Euro has been very consistent. But it does point to more hostile conditions in the MDR than earlier anticipated.

[ConvergenceZone]

Very impressive already. If Franklin isn't the strongest storm of the season my guess is that this one will be. MH potential imo.

There is a real chance 95L could become a Category V hurricane if it recurves out to sea. The MDR at record-warm temperatures.

I agree. Hopefully Bermuda won't be in the track of this one if it does get that strong...

[Stratton23]

The GFS has a notorious bias for making the background environment look unfavorable, and thats simply not true, the environment is primed for this thing to take off, now its a question if this thing goes south of the islands or north, any land interaction will be key

[cycloneye]

The GFS has a notorious bias for making the background environment look unfavorable, and thats simply not true, the environment is primed for this thing to take off, now its a question if this thing goes south of the islands or north, any land interaction will be key

I think you meant south of the Greater Antilles islands right?

[USTropics]

Looking at visible, we have this healthy wave pouch with a distinct AEW troughing pattern (purple) along with our wave axis (green):


This creates an offset mid-level circulation (MLC), that's vaguely outlined here (orange):


What occurs is we have two points of interest along the eastern flank of the pouch, where vorticity is favored on the northern and southern wave axis (highlighted in red):


While a LLC can develop anywhere within the AEW pouch domain, broadly outlined in blue, both vorticity lobes will typical continue to pivot around the mid-level circulation:


We can see this is the general setup analyzed on the 12z GFS:


As far as the short-term forecast, models have backed off on development for two distinct reasons. In the first 72 hours, both the GFS and ECMWF forecast unidirectional shear. This is where we have weak steering currents from the low levels up to the mid level of the atmosphere (highlighted in red). Meanwhile, wind speed is increasing with heights in a consistent direction (pink). This creates a tilted structure that we can see on visible, with a displacement of the mid-level circulation to the west of the wave axis (this is why the western flank of the AEW is convectively active).


While shear relaxes thereafter, consistent vort training of the northern lobe has the moisture envelope associated with 95L more to the north with each run. In addition, models have trended towards a stronger Katia (and trended more south). This creates increased flow directly to the north of 95L, and this begins to strip some of the moisture envelope away:

[Stratton23]

cycloneye yep thats correct

[eastcoastFL]

Hurricane models at least keep it a sloppy mess through 90 hours.