andyhb

1 hour ago, SnowGoose69 said:

The western ridge/East trof pattern is a disaster for the Plains severe weather season.   There are some signs the pattern may shift 5/5-5/10 but by that point many areas of TX/OK are nearing the slowing point of their season which ends around 6/1 usually 

What? Mid-late May is climatological peak season for these areas.

SREF popping a 90 this early (FH 72) is a pretty good indicator of a problem on Thursday.

10+ violent tornadoes and the rest of the numbers usually follow suit. Any outbreak like that automatically earns the title "historic" in my book. Actually any outbreak with more than a half dozen violent tornadoes does so.

There are other factors such as location (see: 5/31/1985) and time of year (e.g. 1/21-22/99, 2/5/08) that also factor in.

2 hours ago, Snowstorm920 said:

Noticing the models are mixing out low level moisture in a large swatch across the risk area during the day tomorrow from surface heating. Check out the surface dewpoint map below. That could really lessen the tornado/severe threat atleast for a time tomorrow afternoon/evening. LCLs get pretty high

 

Pressing X to doubt moisture mixing out that severely so close to the Gulf with unimpeded return flow. Not like the temps are in the upper 90s or 100s either.

Probably worth noting that while the progged warm sector on the models is not especially extensive in terms of northward extent, it is very extensive in the longitudinal (W-E) direction. This matters when you have a setup with westerly winds aloft.

Wouldn't be shocked if we end up with two EF4s out of that lead supercell.

Absolutely nuts.

35 minutes ago, Bob's Burgers said:

It's mine, you can share it if you want on twitter

 

edit. NVM. Shared it on twitter.

Good stuff, retweeted.

1 hour ago, Bob's Burgers said:

Yazoo City (2010), Piedmont (2011), Bassfield (2020)

Not sure if this is yours or if you have a twitter account, but this should be shared.

Yet another EF3 in Columbia’s CWA.

Tornado scars showing up from visible satellite. Saw a lot of this post-4/27/11.

High end damage all around along this portion of the Bassfield-Soso, MS EF4 track.

Debris travelling crazy distances is a hallmark of high end tornadoes (and often high end setups) and this is no exception.

Just now, Calderon said:

I thought that pic was from the 2nd tornado in the Bassfield supercell?

Nope, I believe it is from the first tornado, which dissipated before hitting Bassfield.

Just now, Calderon said:

My problem is the vegetation and grass immediately adjacent to the foundation. One would expect an EF5 to not only have the force to do that to a house, but also chew up the grass and trees around it.

The tree partially laying on the slab is appears to be either a Laurel Oak or Water Oak, but very easy tree to knock over and/or split. It happens frequently in summertime storms in the southeast. A majority in the background were pine, which are softwood and pliable, but there’s a substantial amount of surface bark left.

Unless there is more drastic damage out there we haven’t seen pics of yet, I see it staying at EF4.

LIX keeping it at EF3 as of now.

17 minutes ago, JasonOH said:

Bassfield is a prelim EF4. The trailing tornado is prelim EF2. 
 

 

Tornado from second supercell is prelim EF3. The first tornado from the lead supercell (same that produced the Bassfield EF4) is EF2 (in Walthall County). Just wanted to clarify since this all is quite confusing indeed.

Very intense vegetation damage along this portion of the first tornado's path near Bassfield, MS.

Major tornado just struck Seneca, SC head on. 63.5 dBZ debris ball, TDS bottoming out.

61 dBZ debris ball and I had +73/-134 mph a couple of scans ago, that is a very strong tornado.

Cell near Thomaston, GA looks close to producing and it could be a sig tor if it does.

This whole violent tornadoes on trolley tracks idea is eerily similar to 4/11/65 in S MI.

Cell is taking on more classic supercell characteristics. Cell in behind doing the same.

1 minute ago, WhiteoutWX said:

Im not assuming anything just my interpretation of the data I’m seeing and my own personal forecast. We’ve seen events with much better parameters produce much less than what you are describing. Plenty of events that are hyped days out end up being messy and lacking many strong tornadoes. I could be wrong that’s just my interpretation though. 

The event in January comes to mind. That QLCS was very prolific, produced several long-tracked tornadoes (and several EF2s), and led to several deaths despite instability quite a bit lower than this. There is also a substantial after dark component to this, which extends to the East Coast.

I don't really know what you mean by "what I'm describing". If you're implying I'm saying the doom of the SE is coming on Sunday, that's definitely not it. A high end outbreak is not locked in, but saying brief, weak tornadoes are mostly going to happen with this level of shear and low level moisture regardless of storm mode is also a bit on the extreme side.

6 hours ago, WhiteoutWX said:

I think this setup has some potential, but the strong forcing will likely mean a lot of storms. Hodographs are decent in spots but the VBV signature is there in many of them and critical angles are not very ideal. I think you will see a lot of storms struggling to maintain discrete modes. I would bet on a ton of wind and hail reports with mostly weak/brief tornadoes. If we can get some discrete supercells with some deviant easterly motion there could be a strong tornado or two but I am just not seeing large widespread tornado outbreak out of this setup. 

I'll tell right now that with those shear profiles, VBV isn't going to make a large difference. Also the critical angles are between 45 and 65˚ in most soundings I've pulled, which is well within the typical range seen in Dixie. That's not even accounting for the fact that mesoscale factors can alter critical angles significantly.

On top of that, even with mixed mode here, any embedded spin ups will be producing tornadoes and potentially strong ones with such high 0-1 km SRH (and this continues all the way to the Eastern Seaboard). To assume a mixed mode or even a QLCS here means "brief/weak tornadoes" would be a mistake.

There's more to a "historic" tornado outbreak than just parameters. My biggest concern as of now is early convection mitigating the threat, especially if the warm front has more difficulty lifting north than forecast.

UK and Euro are consistent in a fairly ominous solution, but they also were for 3/28.