ATL: DEBBY - Post-Tropical - Discussion

[aspen]

https://i.imgur.com/W4rdcn4.gif

The convective blowup over Haiti that the GFS has been hinting at might be starting soon.

It’s also on the 12z HWRF, the run that gives 97L the most time over water. If this keeps up through tomorrow morning, we could see the system’s vorticity try to consolidate around the southern coast of Cuba like on the HWRF.

[underthwx]

My question comes after reading this excerpt from the New Orleans AFD...

Now for the elephant. At the moment, global suites are showing the
very large open tropical wave oriented meridionally over Puerto Rico
this morning possibly cutting off a circulation from its northern
end as it reaches central to western Cuba by Sunday or Monday.
This is common in the summer months and its one of the many
things we look for when something is trying to develop. The
steering is fairly straight forward "no pun intended" at first.
This is because the draw will come from the short wave digging
through the midwest this morning. These two features will be
closest when they are meridonal from each other along the 84th
longitude line by late Sat or early Sun with less than 10 degrees
of seperation. This will be the time of greatest draw northward
toward this trough. And whether this develops into a tropical
system or not, the draw of this mass will still be northward
during this time frame. From model perspective, this tropical
feature gets left behind as the short wave quickly swings through
and the tropical cyclone is just not moving fast enough to engage
the trough. This leaves a frontal boundary over or near the coast
and allows the SW CONUS high to then ridge back into the gulf
south blocking this tropical cyclones movement north by late
Monday. This is where models start to have their strongest
disagreement as they differ on how long the keep this ridging
active over the area and timing of the next short wave digging
into the midwest. Nothing to say after Monday at the moment. But a
simimlar solution is found in each model up to that time frame.
Basically, a circulation develops over the eastern
gulf/Florida/Western Atlantic moves northward Sun into Mon before
stalling somewhere near the lat30 line. Now for the biggest
problem with the extended fcast. Every model is bogusing if, when,
how and where they develop this circulation. And this is where
the problem is with fcasting any tropical system; something needs
to actually form first before it can be further assessed as to
what, where and when things will occur. It is always best to keep
up with the latest fcast and make sure you are always prepared,
especially during this time of year.

From what I understand....97L has the possibility of basically stalling/meandering around if it does not get picked up by the shortwave from the midwest?....I know this is a way too early to tell question....if 97L stalls....what are some track scenarios?...

Sound like a discussion from this morning. Things area rapidly evolving and solutions are not out there yet.

...yes....im sorry I left out the discussion time of the NWS New Orleans forecast discussion...it was from the 3:10 am discussion.....

[cycloneye]

That is a lot of rain that WPC is proyecting.

 https://x.com/spann/status/1819120194041643084

[Stratton23]

most of the deeper convection is to the south of the islands, could see a “ center” get pulled more to the south underneath that convection , giving it some more time over water before interacting with cuba, but that also could give it more time over water in the gulf, its the little details that can make a huge difference here

[HurricaneBelle]

With the excessive rainfall projected for the west coast of Florida, this potential Debby is shaping up to be a replay of 2012's Debby. Hopefully it's no stronger than that Debby but moves out quicker.

[jlauderdal]

That is a lot of rain that WPC is proyecting.

 https://x.com/spann/status/1819120194041643084

SE Florida looking good again,for now.

[SouthFLTropics]

I think the area just below the Turks and Caicos and just east of Inagua needs to be watched closely. There is some clear rotation there. May be the mid level center but if it can fire some hot towers it may work its way to the surface.

[ObsessedMiami]

We already have “in house models” from local tv stations.
I can’t say I remember this one
https://x.com/nbergwx/status/1819106009346199953?s=46

[Jr0d]

Expecting a wash here in Key West Saturday. Obviously depending on the path the Florida panhandle may see a significant flood event.

While the wind impact will likely be minimal at best, I do think there will be a even higher than normal chance(for a tropical system)for tornadoes across Florida as it seems like conditions make it favorable for possibly a mini outbreak.

[AtlanticWind]

I am not sure if it is mid level but there seems to be a circulation to
the north of Haiti

[BobHarlem]

Center isn't really obvious on Visible either. I can't get a good feel where this will come together at.

[cycloneye]

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Thu Aug 1 2024

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

Straits of Florida and Eastern Gulf of Mexico (AL97):
A well-defined tropical wave is producing a large area of
disorganized showers and thunderstorms over Hispaniola, the
southeastern Bahamas, and the adjacent waters of the southwestern
Atlantic. The wave is expected to move west-northwestward near or
over Cuba on Friday and then emerge over the Straits of Florida
Friday night or Saturday. Environmental conditions are expected to
be conducive for additional development after that time, and a
tropical depression is likely to form this weekend over the Straits
of Florida or eastern Gulf of Mexico near the Florida Peninsula.

Regardless of development, heavy rains could cause areas of flash
flooding across Florida, Cuba, and the Bahamas through the weekend,
and interests in these locations should continue to monitor the
progress of this system. A NOAA Hurricane Hunter aircraft is
scheduled to investigate this system on Friday, if necessary.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...high...70 percent.

$$
Forecaster Berg

[Hypercane_Kyle]

One thing to watch out for is if this thing develops an LLC south of Cuba. That would dramatically increase its time over water.

[DunedinDave]

Was it Idalia where the center reformed way SE of the center and threw off all the models, eventually leading to landfall in the big bend rather than the panhandle as first forecast? Almost feel like we could be getting a curveball here that are going to force the models to change their trajectory. A storm forming south of Cuba as opposed to north of it would change things, I would presume.

It could also be just a simple thunderstorm blow up south and the center still forms north of Cuba where the mid-level swirl was earlier.

[ConvergenceZone]

It makes sense that it's not doing much now since it doesn't suppose to start organizing until it gets into the eastern Gulf. Like others have pointed out, probably won't be much of a wind maker, but yea could see quite a bit of rain out of it.

[Emmett_Brown]

Just eyeballing it, but if a center is forming, it could be just south of Great Inagua

[cycloneye]

[AL, 97, 2024080200, , BEST, 0, 200N, 728W, 25, 1012, DB][/Div]

[FLLurker32]

When it comes to the panhandle and big bend areas of FL, we do not need much wind to make a very big impact right now.

We’ve had a very active rainy season and many lakes, ponds and rivers are high. They will crest in many areas with a large tropical rain event. The ground is currently saturated and many trees will easily uproot with even TD sustained winds. Most power lines are above ground in this region.

Even a TD in this region right now with enough rain will cause widespread flooding, downed trees and power outages.

The good news? My cousin leads a crew of lineman out of TX. The call was given yesterday for crews to station in Lake City this weekend.

[Stratton23]

Why do i have a weird feeling this is going to pull an Ivan , making a big loop off the SE US - Florida Coast, and make a 2nd landfall in florida? Some of the 18z GEFS members do show this happening, the steering pattern is so erratic, i could be wrong, but just a funny feeling about this one

[Michele B]

When it comes to the panhandle and big bend areas of FL, we do not need much wind to make a very big impact right now.

We’ve had a very active rainy season and many lakes, ponds and rivers are high. They will crest in many areas with a large tropical rain event. The ground is currently saturated and many trees will easily uproot with even TD sustained winds. Most power lines are above ground in this region.

Even a TD in this region right now with enough rain will cause widespread flooding, downed trees and power outages.

The good news? My cousin leads a crew of lineman out of TX. [color=#BF0000]The call was given yesterday for crews to station in Lake City this weekend.

[/color]

Now THAT's the kind of "inside information" that is useful!

Thank you for that. It gives us a glimpse into what tptb are thinking.