andyhb

20 minutes ago, Quincy said:

The synoptic pattern has multiday potential, but I’ve learned to be skeptical until the day of. 

All of the hype lately (mainly talking about social media and news outlets, not here) is way overblown. Last week was supposed to be some historic event and it was mostly a dud. Every forecast trough is supposedly the “best setup in years” according to some. It’s really muddying the waters and desensitizing the general public.

Big trough in spring ≠ mega outbreak. 

Despite living in Oklahoma, I’ll most likely be sitting these events out. With the hype and potential location, it will be a zoo storm chasing anyway.

Being the rebel that I can sometimes be, I’ll be out in West Texas today and tomorrow. There’s a low probability for an isolated supercell both days. Sure, nothing might happen, but I’d prefer to be out when it’s quiet, rather than a circus. 

I'm going to tell you right now that that's probably a mistake on Thursday.

Going to need a dedicated thread somewhere/anywhere for the 4/25-28 potential severe sequence. 00z model runs in so far are rather alarming.

Looks like a fairly large tornado here near Barr IL.

Tornado trying to form on the west side of DVN right now.

https://livestormchasing.com/chasers/brett.adair

Tornado was in progress on this stream.

Cell in far SE IA looks poised to produce a sig tor.

Tornado in progress on this stream NW of DMX.

This first round has been notably cellular especially south of the IA/MO state line.

18z Euro was very impressive for tomorrow and probably worthy of a MDT risk. Gives ample time to destabilize with 300+ m2/s2 0-1 km SRH becoming common along a 50 kt LLJ over SE IA, NE MO, and far W IL by 21z. Signal is for a discrete/semi-discrete band of cells along the arcing Pacific front/dryline with better lapse rates thanks to CAA aloft closer to the primary upper low.

There are a number of larger synoptic N MO/IA events that looks like this one at 500 mb (5/27/1995, 4/8/1999, 3/31/2023, 4/11/2001 amongst them), and the dryslot in the mid levels as 700-500 mb, which is absolutely paramount for these types of events, looks pretty potent. I also noticed that most of the CAMs, despite different evolutions, ended up with robust cells with strong UH across some portion of the region, both at 12z and 18z.

CIPS analogs are absolutely jacked for Tuesday in the Mid Mississippi Valley. Going to be pending convection from Monday I'm sure, but the setup seems to be there for a significant and potentially widespread event.

Tuesday also looks like a potentially significant severe event over AR and MO primarily depending on what occurs overnight Monday into Tuesday morning. Very strong flow with the ejecting wave and a substantial dryslot aloft to aid in renewed destabilization. Additionally there appears to be a diffuse Pacific front/dryline pushing east.

Just now, Wmsptwx said:

Euro trending down, blocking hurting this

There isn't really much blocking in the northern latitudes right now.

Not going to to get much more into specifics on this one right now, but the trough ejection on multiple models here looks favorable for a higher end threat, especially in Oklahoma.

Supercell on that boundary in the Austin area could be bad news, especially with rush hour on I-35.

Looks like a tornado approaching West Union OH with the same storm.

Strong tornado in progress in E TN NE of Wartburg right now.

Edit: also a tornado in progress NE of Louisville.

Significant tornado in progress in central WV.

Also its 71/64 with a south wind at Covington KY (Cincinnati metro) rn. Anyone calling bust/counting out at least SW OH for later needs to take a step back.

A lot of convection over OK and MO that is going to need to be worked out before we figure what tomorrow's ceiling is. I will say that this is on the "more inhibitive" side in terms of convective coverage from what I've seen in past events.

Outbreak potential with intense/long-tracked tornadoes mentioned in that outlook.

12z HRRR was knocking on the door of a high risk for IN/OH.

Yeah there's definitely something eerie about a potentially significant severe threat one day before the 50th anniversary of, hands down, the worst tornado outbreak to ever affect the Ohio Valley.

Probably should consider a separate thread for this one soon. The 12z NAM also brought back a significant threat after losing it at 00z.

Yes the 18z NAM is absolutely nasty on Tuesday. Granted, that probably won't hold, although its 500 mb setup isn't much different than the other models.

The low levels will make or break this along with prior convection from Monday.