SE Area of Interest--0% two day, 30% five day odds

[WxWatcher007]

Ok, so normally we wouldn't have threads for current low probability systems, but I guess we're changing that this year. This comes from my bigger overview, which highlights this area of interest. I've been quietly watching for days, and now it's worth discussion. 

This area of potential has been much more interesting than 95L, and has been for a while now for the reasons below. Yesterday most probably sat up as the happy hour GFS showed a strong system attempt to develop in the wake of 95L off the same frontal boundary, this time getting shunted back into the US. Well, although that run of the GFS was way too aggressive, the signal for some sort of follow up development has been on the guidance for a few days now. It's not terribly hard to see why, as the environment looks at least marginally favorable for some development. 

Vorticity

First--the frontal boundary is usually good for getting some vorticity spin up. This fits with climatology. So if something is far enough off the coast there should be some sort of spin that develops in the coming days. Both models pick up on this in the medium range. 

This is not enough for TC genesis. Which leads to the second favorable factor.

Instability

While the tropical Atlantic has been incredibly stable so far this season...

There has been no such issue off the East Coast...in fact, instability has been extremely high. 

What that tells me is that anything that does have spin and can develop an area of low pressure will have a chance to generate convection, which will only help with TC genesis odds as long as the system isn't hugging land the entire time. 

SSTa

Not much analysis needed here. I expect the the southwest Atlantic to be a hotbed of activity this season because that's where the heat is. Any low is going to have a shot with enough time and space to become tropical in this SSTa regime. 

Shear

The key inhibitor here is shear. Often times with these frontal boundary systems near the coast you have shear and drier air that is lurking. That comes with the territory with the frontal boundary. Here it is unclear how favorable a shear environment this potential system will find, but guidance is hinting at a window of lower shear later this week taking hold. 

What makes this particularly interesting is the steering pattern. While the outcome is different in terms of where the area of vorticity goes, the pattern evolution is the same. In the wake of 95L a ridge builds in and traps whatever could develop along the coast. That's something to legitimately watch. Maybe not closely, yet, but at least with a casual eye.  

[BarryStantonGBP]

7 minutes ago, WxWatcher007 said:

In before Barry takes the thread lol. Working on a real OP. 

Hi!

 

3. Off the Southeastern United States:
An area of low pressure could form in a couple of days a few hundred 
miles southeast of the Carolinas.  Some gradual development of this 
system is possible by midweek as the system drifts to the 
northwest. 
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

[WxWatcher007]

7 minutes ago, BarryStantonGBP said:

Hi!

 

3. Off the Southeastern United States:
An area of low pressure could form in a couple of days a few hundred 
miles southeast of the Carolinas.  Some gradual development of this 
system is possible by midweek as the system drifts to the 
northwest. 
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...20 percent.

I had to beat you to the punch haha

[BarryStantonGBP]

Just now, WxWatcher007 said:

I had to beat you to the punch haha

it is ogre 

chances this develops into a bonafide tc?

[GaWx]

Upped from 20% to 30%:

2. Off the Southeastern United States:
A broad area of low pressure is forecast to form in a couple of 
days a few hundred miles off the coast of the southeastern United 
States. Some gradual development of this system is possible during 
the middle or latter part of the week as the system drifts to the 
west or northwest. 
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.