Severe WX Severe Weather Event April 13-14, 2019

[andyhb]

00z Euro holds serve with a very dangerous looking setup from early afternoon Saturday through Sunday. There are some notable similarities here to the Nov 21-23, 1992 event across this same region, which was, of course, a very significant tornado event with a large after-dark component.

I don't currently see any reason why storms won't keep raging through the night here, and they look like they could very well stay discrete/semi-discrete.

 

[Fred Gossage]

The 1992 analog is a very good synoptic one, except for one difference. I think the higher-end stuff would start north/northeast of where it did that event because of the low-level jet waiting until the MS River to really ramp up. I think the tornado threat starts out in Texas, and the higher-end threat starts in northeast LA and southeast AR... but this feels like it's pointed at MS/AL/TN/eventually GA.

 

[Daryl]

 

[CheeselandSkies]

PDS TOR soundings abound across E. TX and most of LA on both NAM and GFS 06Z runs valid for 18Z Saturday, which as as far out as they go. No reason to think 12Z won't be similar.

 

[Kory]

I'd suspect if the timing of the system wasn't falling across the SPC cut off between outlooks, we'd have a 30% look extending into AL. I don't see us escaping at least a moderate risk out of this. Again, I've yet to find a significant mitigating factor for us.

Euro/UKMET have plenty of convection across the free warm sector beginning earlier Saturday night.

 

[Kory]

End of the SREF run, and we're already at 60% sig tor probs.

 

[MattPetrulli]

PDS TOR soundings abound across E. TX and most of LA on both NAM and GFS 06Z runs valid for 18Z Saturday, which as as far out as they go. No reason to think 12Z won't be similar.

NAM is pretty big at 18z indeed, SREF already popping a 60% contour on frame 30. 4/2/17 comes to mind thinking about this setup. We escaped substantial damage that day, but there were a lot of serious signatures on radar with debris and a few tornado emergencies. This time however, we're looking at a more widespread threat that will probably continue into the overnight hours in MS/AL, something that didn't occur with 4/2/17. Also 4/2/17 had a messy warm sector, so that'll be the big question here as we approach the setup.

 

[Kory]

NAM is pretty big at 18z indeed, SREF already popping a 60% contour on frame 30. 4/2/17 comes to mind thinking about this setup. We escaped substantial damage that day, but there were a lot of serious signatures on radar with debris and a few tornado emergencies. This time however, we're looking at a more widespread threat that will probably continue into the overnight hours in MS/AL, something that didn't occur with 4/2/17. Also 4/2/17 had a messy warm sector, so that'll be the big question here as we approach the setup.

Looks like a large EML will slide in ahead of the system capping most of the warm sector until later in the evening and overnight. And by that time, deep layer shear would probably keep storms quite organized, reducing junk convection.

 

[CheeselandSkies]

NAM is pretty big at 18z indeed, SREF already popping a 60% contour on frame 30. 4/2/17 comes to mind thinking about this setup. We escaped substantial damage that day, but there were a lot of serious signatures on radar with debris and a few tornado emergencies. This time however, we're looking at a more widespread threat that will probably continue into the overnight hours in MS/AL, something that didn't occur with 4/2/17. Also 4/2/17 had a messy warm sector, so that'll be the big question here as we approach the setup.

That's the day I just had in mind as one that didn't turn out quite as dangerous as first thought...it too was being compared to the November 1992 outbreak in the days leading up to it.

 

[CheeselandSkies]

I am seeing some unidirectional winds on the soundings from somewhere between 850 and 700mb on up to 500mb...winds don't really start veering again until 500mb. Excellent turning from the surface to just above 850mb, though with very strongly backed surface winds.

 

[MattPetrulli]

That's the day I just had in mind as one that didn't turn out quite as dangerous as first thought...it too was being compared to the November 1992 outbreak in the days leading up to it.

Yeah November 1992 comes to mind thinking about this setup also. Just without the northern extent into the Midwest.

 

[warneagle]

I noticed that the NAM pops a couple of Palm Sunday 1994 analogs in LA at 18z on Saturday. Yikes.

 

[andyhb]

Goodness gracious the soundings on the 12z NAM for Saturday in E TX and LA are insane. Long range NAM, but not really surprising given what the GFS/Euro have been putting out for days now.

 

[amp1998]

Not surprising to see PDS TOR soundings with this kind of set up shown below.

 

[Richardjacks]

The timing and placement of the 500mb jet max is very concerning considering the instability and low level parameters.

 

[Kory]

I don’t suspect we’ll see any major synoptic changes here on out. All of the major players are within upper air sampling locations.

 

[NWMSGuy]

Any thoughts on the Memphis area with the low tracking just to the west or right overhead?

 

[tennessee storm chaser]

Any thoughts on the Memphis area with the low tracking just to the west or right overhead?

Not going pull the best dynamics in with warm front ... before frontal boundary passes ... ton heavy rain n some wind ... next weeks system different tune... but on this threat ... not seeing any red alert for now

 

[N4GKS]

I noticed that the NAM pops a couple of Palm Sunday 1994 analogs in LA at 18z on Saturday. Yikes.

I noticed that too. Don’t like to read anything into this by means of comparison, but again, I noticed too.

 

[MattW]

SPC has a 15% area on D5 (Sunday) for a chunk of Georgia, but the GFS doesn't have a lot of good ingredients showing. What am I missing? Is that just too far out for the GFS?