ATL: DELTA - Post-Tropical - Discussion

[cycloneye]

Shower and thunderstorm activity has become more consolidated since
yesterday near a tropical wave located over the central Caribbean
Sea. Environmental conditions are expected to become more conducive
for development, and a tropical depression could form next week
while the system moves westward or west-northwestward at about 15
mph across the central and western Caribbean Sea and then into the
southern Gulf of Mexico. Locally heavy rainfall and gusty winds
will be possible across portions of Hispaniola, Jamaica, Cuba, and
the Cayman Islands during the next few days, and interests on those
islands should monitor the progress of this disturbance.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 5 days...medium...60 percent.

[cp79]

Why do I get the feeling we are in for a wild week. We hand everyone getting Covid now, including politicians and a football players. You have two storms about to enter and drift around in the Gulf. Halloween is approaching. Crazy times coming.

[chaser1]

Despite the favourable conditions models don’t even really seem to develop 92L. Wonder if there’s some underlying factor they’re seeing that we’re not?

Water Vaper satellite depiction shows the pretty sharp delineation of the TUTT immediately up against the disturbance with the direct SW mid to upper level flow impacting the disturbance. On one hand, this might well be a catalyst for 92L genesis but at the same time capping near term development by disrupting convection from remaining over center. At the southern end of this TUTT cuts off over the next day or two, we'll just have to wait and see how fast (and where) this cut-off moves and how quick it weakens. If the "center" of 92L orientates itself north or northeast of any cut-off, quicker paced development would likely occur. Everything right now is so fluid and progressive that it's a bit hard to see how it all will play out. Models remain less consistent depicting meso-scale genesis and intensity, while the Euro seems best fit for future track analysis.

[chaser1]

Why do I get the feeling we are in for a wild week. We hand everyone getting Covid now, including politicians and a football players. You have two storms about to enter and drift around in the Gulf. Halloween is approaching. Crazy times coming.

Must be a full moon lol

[FireRat]

Why do I get the feeling we are in for a wild week. We hand everyone getting Covid now, including politicians and a football players. You have two storms about to enter and drift around in the Gulf. Halloween is approaching. Crazy times coming.

Must be a full moon lol

Make that 2 full moons lol! Blue Moon on 10/31, Halloween, spooky times indeed!
I'm also on the October being nuts bandwagon, count me in!

[AtlanticWind]

We are talking east coast metro areas of SFL dade and broward counties which believe it or not only saw sustained strong TS winds during Irma.

I get it, but that’s a postage stamp size parcel of real estate. It’s tough to get a landfall in specific areas like that. The force field is a fun myth.

Anyway, 92L won’t be a LF threat to the E coast anyway.

SE Florida has been way overdue for a hurricane. Fortunately this part of Florida hasn’t seen a landfalling hurricane since Katrina in 2005. Though Wilma that year did also bring hurricane conditions to parts of SE Florida.

Wilma bought Cat 1 conditions to ALL of dade ,broward and palm beach counties and Cat 2 conditions
to many parts of these counties.

[chaser1]

I get it, but that’s a postage stamp size parcel of real estate. It’s tough to get a landfall in specific areas like that. The force field is a fun myth.

Anyway, 92L won’t be a LF threat to the E coast anyway.

SE Florida has been way overdue for a hurricane. Fortunately this part of Florida hasn’t seen a landfalling hurricane since Katrina in 2005. Though Wilma that year did also bring hurricane conditions to parts of SE Florida.

Wilma bought Cat 1 conditions to ALL of dade ,broward and palm beach counties and Cat 2 conditions
to many parts of these counties.

I'll say! I was in W. Pembroke Pines and Wilma brought quite a punch. I and many others had significant roof damage from that storm.

[boca]

I sure seems like we are in the safe zone here in SE Florida and our streak continues, but not so for the panhandle and northern gulf coast.

[cp79]

I sure seems like we are in the safe zone here in SE Florida and our streak continues, but not so for the panhandle and northern gulf coast.

For 92L? I don’t think anyone in Florida on the west coast is in the clear yet.
Looks like it could take a similar track to Dennis four the next 96 hours before it drifts more west into the central gulf.

[chaser1]

If 92L could essentially "sit in place" it sure seems like a small upper level anticyclone would build over it in the wake of the cut-off low to it's west quickly pinching off the southern extension of the TUTT that extends over and south of Hispaniola. One other oddity about this season is how most Octobers seems to stagnate westward progression of tropical waves, and overall "motion" within the tropics - even west Caribbean generally begins to crawl to a very slow process. Gyre related development over Central America seems to take forever to develop. At least for now, we continue to see relative quick T.S. development and rate of strengthening (as Gamma has shown). Will be interesting to see if this continues with 92L, and others to follow. Bigger question is for how long?

[edu2703]

 https://twitter.com/HurricaneManWx/status/1312477453613293568

[chaser1]

I sure seems like we are in the safe zone here in SE Florida and our streak continues, but not so for the panhandle and northern gulf coast.

For 92L? I don’t think anyone in Florida on the west coast is in the clear yet.
Looks like it could take a similar track to Dennis four the next 96 hours before it drifts more west into the central gulf.

I think that as long as the W. Caribbean has a penchant for tropical storms to develop, South and Central Florida continue to run the risk of a storm moving northward to NNE into the lower half of the state. Right now we are interestingly still in a point of this season where the pattern is pushing storms off to the northwest. After this recent cold front I pretty much expected the typical fall pattern to transition and 92L might then had been a significant risk to Florida. Point is, we're simply not there yet. Not sure if we truly evolve to that Fall like pattern in a couple weeks or remain with general mid level ridging over the Southeast Conus for some time to come? One thing to remember is that La Nina like conditions are just now beginning to reverberate and it may well be that this recent strong "cool front" was more an aberration then a sign of more to come any time soon.

[cp79]

The Million dollar question is where does it begin the north turn and at what angle. That’s gonna play a big role in obviously Fla’s forecast. Euro has it moving more wide and into the Central Guld while the GFS Para gets it close to the west coast, giving them nasty weather. Where the center forms is obviously a big player in that.

[aspen]

Vorticity still looks good and is very close to 92L's convection.


I've marked up the MPI map with 92L's potential tracks. It'll likely be in the vicinity of Jamaica going into Monday and possibly as a developing or developed TC. From there, there are two main solutions by the models right now: a further NE track that goes through Cuba and is closer to Florida (white, has been seen with the GFS-Para), or a further SW track that only clips the far end of the island (red, 12z Euro run). I've also marked what I think is the most SW solution possible, which so far isn't shown by any of the models, but isn't impossible.


Any of the SW solutions that minimize or prevent land interaction with Cuba will give 92L/Delta roughly 48-60 hours over 29-31C SSTs and (potentially) low shear, assuming there's a defined TC at 36-48 hours out (mid-Monday). Gamma only had 27 hours between formation and landfall over similarly warm SSTs, and it very rapidly organized into a 70-80 mph TS/C1. If the environment is as favorable as SHIPs predicts it will be, Delta's ceiling will be very high.

[us89]

Up to 40/70

A tropical wave located over the central Caribbean Sea is producing
an area of disorganized showers and thunderstorms. Environmental
conditions are expected to become more conducive for development,
and a tropical depression is likely to form during the early or
middle portions of next week while the system moves westward or
west-northwestward at about 15 mph across the central and western
Caribbean Sea and then into the southern Gulf of Mexico. Locally
heavy rainfall and gusty winds will be possible across portions of
Hispaniola, Jamaica, Cuba, and the Cayman Islands during the next
few days, and interests on those islands should monitor the progress
of this disturbance.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 5 days...high...70 percent.

[toad strangler]

Did this thing go poof? Sure looks like it.

[AnnularCane]

Did this thing go poof? Sure looks like it.

They don't raise percentages on things that go poof.

[TheStormExpert]

Did this thing go poof? Sure looks like it.

Still wouldn’t take much once conditions become more favorable as it has a very defined circulation.

[robbielyn]

Did this thing go poof? Sure looks like it.

Still wouldn’t take much once conditions become more favorable as it has a very defined circulation.

at the mid level no llc

[cycloneye]

A tropical wave accompanied by a low pressure system is located over
the central Caribbean Sea a couple of hundred miles southeast of
Jamaica. The associated shower and thunderstorm activity is
beginning to show some signs of organization. Environmental
conditions are expected to be conducive for additional development,
and a tropical depression is likely to form within the next day or
two. The system should move west-northwestward at 10 to 15 mph
across the central and western Caribbean Sea today through Tuesday,
and then move into the southern or southeastern Gulf of Mexico on
Tuesday night and Wednesday. Locally heavy rainfall and gusty
winds will be possible across portions of Hispaniola, Jamaica, Cuba,
and the Cayman Islands during the next few days, and interests on
those islands should monitor the progress of this disturbance.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...80 percent.