Severe WX Severe Weather Threat 10/31-11/2

[Kory]

It won’t take much to slow this down another 3-6 hours. This was looking like an overnight threat for most of Dixie. Now it appears early morning. The trend has been to slow it down.

And then the Euro with a solution that would certainly be potent...

 

[rolltide_130]

Lots of timing inconsistencies. The NAM has mysteriously trended down with the CAPE (granted it's still sufficient even as is but I have no idea why its trending it down) and still wants to old onto the overnight idea.

Now if we trend towards the Euro.. this is a potential significant tornado event.. that's all I'm going to say about that..

 

[Kory]

The NAM is sliding the cold front out ahead as the trough is flatter. That's why we're seeing it backpedal.

Flatter trough = faster timing. Vice versa for sharper trough.

 

[tennessee storm chaser]

Lots of timing inconsistencies. The NAM has mysteriously trended down with the CAPE (granted it's still sufficient even as is but I have no idea why its trending it down) and still wants to old onto the overnight idea.

Now if we trend towards the Euro.. this is a potential significant tornado event.. that's all I'm going to say about that..

Yeah. Euro also has a broader base. Trough ... which also leads more tornadic activity

 

[Kory]

Euro looks rough for Thursday.

 

[rolltide_130]

Euro looks rough for Thursday.

Continuing to slow it down as well. The NAM seems like its becoming the outlier in terms of both strength and timing..

 

[Kory]

The euro does have a bias of hanging energy back in the SW longer than normal. But this continues to slow. Will be interesting at 00z.

 

[warneagle]

The 12z NAM also kept the surface low down near the coast, which is an outlier.

 

[rolltide_130]

The 12z NAM also kept the surface low down near the coast, which is an outlier.

Yeah I'm beginning to think the NAM had a bad run. It just completely sheared out the trough and didn't even generate a sfc low where it should have. Looking forward to seeing what the 18z run does. Every 24-36 hours leading up to severe events you get a NAM run that just makes no sense..

 

[Kory]

SREF looks very Euro-ish through 54 hours.

One thing of note, there is a lot of forcing near the Gulf Coast. This may introduce some coastal convection problems, if it is not limited to just along the frontal boundary.

 

[rolltide_130]

SREF looks very Euro-ish through 54 hours.

One thing of note, there is a lot of forcing near the Gulf Coast. This may introduce some coastal convection problems, if it is not limited to just along the frontal boundary.

On the SREF it didn't seem terrible. Forcing down there but it seems to line up with forcing further inland if I"m reading properly. So far there doesn't seem to be a particularly strong signal for stuff to go up way ahead of the frontal boundary either inland or on the coast but I could be reading it wrong/it could change.

 

[rolltide_130]

With that said.. on the Euro however, there could be two waves of storms both with a good thermo and kinematic environment to work with.. the Euro is a very dangerous situation if there is indeed no convective feedback on the coast..

 

[amp1998]

18z NAM has slowed down about 6 hours.

 

[Taylor Campbell]

Wow at the differences in just an 84 hour period. EURO is a different animal. More of its ensembles are trending slower, and it looks like the NAM is trending slower with it.

 

[warneagle]

So far the 3km NAM isn't really developing much coastal convection (although that's only through 06z on Thursday). And the 18z NAM is slowing it down some now.

 

[rolltide_130]

I think the Euro was the one with the coastal convection, but based on how it looks it looks like by the time the coastal convection was even in a position to impact things the initial line had already moved into North AL. I haven't seen any models indicating a big blocking convective blob along the coast hours ahead of the front just yet.

 

[CheeselandSkies]

SPC really playing this one low-key, not that that's the wrong thing to do what with the uncertainty but they might find themselves having to ramp up the wording sharply for Day 3.

 

[Kory]

18z GFS has trended slower...again. Globals seem to be going toward the Euro.

 

[rolltide_130]

18z GFS has trended slower...again. Globals seem to be going toward the Euro.

I think we're beginning to look at a solid midday to afternoon event on Thursday.. the primary uncertainty now is this Gulf convection that doesn't seem overwhelming at the moment and we may not know much about until 24 hours out..

 

[amp1998]

And several of the European ensemble members slow down to a late afternoon Thursday/evening hours.