Severe WX Severe Weather 4/24-4/26

[Kds86z]

This is one of those setups where the signal is clearly there at the synoptic scale, and that’s why confidence in something happening is pretty high. The global guidance has been fairly consistent run to run with a negatively tilted trough ejecting into the Plains, strong lee cyclogenesis, and a broad warm sector with quality moisture return. That’s not a messy or disorganized look, it’s a classic late April pattern that usually produces at least one legitimate severe weather day. The overall structure of the system, especially the timing of the trough and the strength of the low level response, supports a scenario where the atmosphere is primed across a large area rather than just a narrow corridor.

Sunday still jumps off the page in terms of raw environment. You’re looking at MLCAPE in the 3000–4000 J/kg range, deep layer shear around 45–60 knots, and a strong low level wind field with backed surface flow near the dryline and any warm front intersection. On top of that, there’s a stout elevated mixed layer in place, which is both the reason the ceiling is so high and the main limiting factor. The environment ahead of the dryline is about as classic as it gets for a Plains setup, which is why people keep calling it a loaded gun type look. The issue isn’t whether the atmosphere can support significant severe weather, because it clearly can, the issue is whether storms actually initiate in the right place and at the right time. The GFS in particular has been showing relatively limited QPF despite strong large scale ascent, which points toward capping concerns. At the same time, that’s a known bias, especially in these EML driven setups where it tends to hold the cap too long. If that cap holds, you end up with a frustrating underperforming day where nothing really takes advantage of the environment. But if it breaks in a focused window, even briefly, storms would likely become rapidly organized and discrete, and with shear vectors largely perpendicular to the dryline and strong low level hodographs, that would favor supercells capable of producing significant severe, including long track tornado potential. You don’t need a lot of storms in an environment like that, one or two sustained supercells could end up verifying the entire risk.

Monday looks more like a downstream continuation of the pattern, with stronger forcing and a broader spatial footprint. The environment still supports severe weather, with MUCAPE generally in the 2000–3000 J/kg range, around 40 knots of bulk shear, and a wide warm sector extending from Louisiana and Mississippi up into Tennessee and Kentucky. The difference here is that initiation is much less of a concern, and the setup leans more toward widespread convection rather than isolated storms. That brings its own tradeoffs, because while the ceiling might not be quite as extreme as Sunday in a pure sense, the overall threat becomes more reliable and covers a larger area. Storm mode becomes more of a question, with potential for a mix of supercells and organized lines, but the parameter space still supports all hazards. The big wildcard with Monday is how much Sunday influences it. If Sunday produces widespread convection, that could work over the atmosphere and limit instability somewhat on Monday. If Sunday underperforms or stays capped, then Monday could inherit a more undisturbed environment and end up with a higher ceiling than it might otherwise have.

The way the pattern is evolving, this really looks like a multi day severe setup where at least one day is likely to produce a significant event. Sunday has the higher ceiling and the more classic look for discrete supercells, but it’s conditional on the cap breaking. Monday has a lower ceiling in a vacuum, but a much higher floor in terms of storm coverage and overall impact. It wouldn’t be surprising at all to see Sunday end up as a more localized but potentially high end day if storms can initiate cleanly, while Monday ends up being a broader, more widespread severe event affecting a larger population. Right now, Sunday still stands out as the day where if everything comes together it could really go big, especially near the dryline and any boundary intersections, but Monday is arguably the more dependable threat given the stronger forcing and larger scale support. Overall, the ceiling on this entire setup is very high, it’s just a matter of which day actually takes full advantage of the environment.

Big discussion there sir @Brice W . Bravo

 

[JPWX]

You know I use to think the previous storms from the last day could limit instability for a threat the next day. That was until 15 years ago. Then years going forward I learned about storms leaving leftover outflow boundaries. That being said, I would really be hesitant to say that storms from Sunday would limit Monday's threat. This is definitely not going against what @Brice W said and yes, there's still a lot of mesoscale unknowns. But this does appear to be headed towards the biggest threat we will have this April and (depending on one's point of view) thus far this year.

 

[UncleJuJu98]

Man. I really hope the 12z euro is wrong. I think a day 7-8 severe outline is coming for dixie.

Also Monday is rather impressive for Mississippi. Color me shocked if a 30% is not introduced by tommrow.

 

[Cyclonic Paracosm]

Not getting into the specifics, but the ongoing GFS has NEARLY 500-700 0-3 KM SRH and 50-60 knots of shear in Northern Oklahoma at 03z. If you blew out a candle the smoke leftover from it would be rotating in that environment

is hella rare to have a env that potent just not convect, doesn't mean thats the case sunday but I'd still keep an eye out

 

[Weatherguyx]

 

[Tennie]

In a way, this upcoming setup and the one following right behind remind me at least somewhat of the 2024 season and how that exploded into action in late April after a comparatively quiet early season. I just hope it doesn’t get TOO chaotic once things start lighting off.

 

[UncleJuJu98]

Yup that's why I was posting I hope the 12z euro was wrong. NASTY look for the deep south. If that maintains that'll overshadow Monday for the deep south.

 

[tennessee storm chaser]

Don’t think instability will be lacking either day Sunday or Monday …. Todays runs actually bumped cape up ever so slightly

 

[Tennie]

Yup that's why I was posting I hope the 12z euro was wrong. NASTY look for the deep south. If that maintains that'll overshadow Monday for the deep south.

Well, at least it won’t be on a Wednesday.

(Side note, I can’t help but wonder if the main reason the 3/15/2025 outbreak failed to reach its ceiling was because it didn’t happen on a Wednesday...)

 

[tennessee storm chaser]

Yup that's why I was posting I hope the 12z euro was wrong. NASTY look for the deep south. If that maintains that'll overshadow Monday for the deep

Yup that's why I was posting I hope the 12z euro was wrong. NASTY look for the deep south. If that maintains that'll overshadow Monday for the deep south.

Question the quality moisture return a
Bit . Models still not In agreement. But still early
.

 

[UncleJuJu98]

Question the quality moisture return a
Bit . Models still not In agreement. But still early
.

Itll be good enough, we may not have extreme moisture, but late April/ early may will easily have enough.

 

[tennessee storm chaser]

Itll be good enough, we may not have extreme moisture, but late April/ early may will easily have enough.

I’m paying close attention. Just Buisy week shaping up weather wise

 

[WeathermanLeprechaun]

Alright, let's get into it.

A severe weather sequence (potentially potent) is en route to the Central/Southern Plains and Midwest/Dixie Alley.

Thursday will kick it off with the potential for a couple embedded tornadoes and significant damaging winds in S KS/N OK and propagating east.

Friday: a day off type event with all hazards being possible but relatively low chance in the arlatex

Saturday: truthfully no idea why the 30% was pulled but there is a signal for all hazards, wind and hail main threat but tor threat not ruled out in OK.

Sunday: A big day, with a high end environment but plenty of thermodynamic issues.

This will be a hot take but I would've stuck with the 15%. The SPC knows best and pattern recognition is key, but the uncertainty here and confidence is just rife. There's a high end environment but i feel like the 30% was premature. This is a tough system to predict and there may be sig all hazards if cells initiate. This is a classic boom or bust day.

Monday: i calculated the jet translation speed and this was 40 kts from E NM at 06z to Central IL at 00z on Tuesday. This day contains a large, spatial warm sector with a strong LLJ, and in my opinion across the mid south needs to be watched very closely. This is probably the most potent threat out of all of these days. The amount of instability we are getting, the kinematics line up and a fast jet may lead to a significant svr weather event here. Monitoring closely.

 

[eep]

Alright, let's get into it.

A severe weather sequence (potentially potent) is en route to the Central/Southern Plains and Midwest/Dixie Alley.

Thursday will kick it off with the potential for a couple embedded tornadoes and significant damaging winds in S KS/N OK and propagating east.

Friday: a day off type event with all hazards being possible but relatively low chance in the arlatex

Saturday: truthfully no idea why the 30% was pulled but there is a signal for all hazards, wind and hail main threat but tor threat not ruled out in OK.

Sunday: A big day, with a high end environment but plenty of thermodynamic issues.

This will be a hot take but I would've stuck with the 15%. The SPC knows best and pattern recognition is key, but the uncertainty here and confidence is just rife. There's a high end environment but i feel like the 30% was premature. This is a tough system to predict and there may be sig all hazards if cells initiate. This is a classic boom or bust day.

Monday: i calculated the jet translation speed and this was 40 kts from E NM at 06z to Central IL at 00z on Tuesday. This day contains a large, spatial warm sector with a strong LLJ, and in my opinion across the mid south needs to be watched very closely. This is probably the most potent threat out of all of these days. The amount of instability we are getting, the kinematics line up and a fast jet may lead to a significant svr weather event here. Monitoring closely.

TBF Thursday has a pretty potent conditional threat in OK too with the dryline, if that were to fire there would be a true supercellular tor event.

 

[Kds86z]

Alright, let's get into it.

A severe weather sequence (potentially potent) is en route to the Central/Southern Plains and Midwest/Dixie Alley.

Thursday will kick it off with the potential for a couple embedded tornadoes and significant damaging winds in S KS/N OK and propagating east.

Friday: a day off type event with all hazards being possible but relatively low chance in the arlatex

Saturday: truthfully no idea why the 30% was pulled but there is a signal for all hazards, wind and hail main threat but tor threat not ruled out in OK.

Sunday: A big day, with a high end environment but plenty of thermodynamic issues.

This will be a hot take but I would've stuck with the 15%. The SPC knows best and pattern recognition is key, but the uncertainty here and confidence is just rife. There's a high end environment but i feel like the 30% was premature. This is a tough system to predict and there may be sig all hazards if cells initiate. This is a classic boom or bust day.

Monday: i calculated the jet translation speed and this was 40 kts from E NM at 06z to Central IL at 00z on Tuesday. This day contains a large, spatial warm sector with a strong LLJ, and in my opinion across the mid south needs to be watched very closely. This is probably the most potent threat out of all of these days. The amount of instability we are getting, the kinematics line up and a fast jet may lead to a significant svr weather event here. Monitoring closely.

Tomorrow could be interesting in Ks. Supercells .

 

[akt1985]

There is also the chance the main batch of severe storms doesn’t get to Alabama until Tuesday morning, April 28.

 

[Clancy]

Itll be good enough, we may not have extreme moisture, but late April/ early may will easily have enough.

Yeah, moisture return is definitely not a concern here.

 

[Schoeppeya]

Maybe somebody smarter than me can break this down but some pretty key differences being shown between the GFS and Euro for Sunday evening.... The 18z Euro is painting an extremely impressive environment with extremely high CAPE, and 3cape levels over 100, so a very moist uncapped lower level environment with very strong shear. I think storms easily convect if thats the environment that verifies and probably a high risk type day. The GFS continues to show very strong wind shear but much much lower 3cape values, some below 50 for the same locations as the Euro implying a much less moist and bouyant environment and I think if that verifies we probably watch skinny little towers go up all afternoon that never really establish and the cap wins. I dont know if either of those is typical model biases but something to watch!

 

[Ozonelayer]

Maybe somebody smarter than me can break this down but some pretty key differences being shown between the GFS and Euro for Sunday evening.... The 18z Euro is painting an extremely impressive environment with extremely high CAPE, and 3cape levels over 100, so a very moist uncapped lower level environment with very strong shear. I think storms easily convect if thats the environment that verifies and probably a high risk type day. The GFS continues to show very strong wind shear but much much lower 3cape values, some below 50 for the same locations as the Euro implying a much less moist and bouyant environment and I think if that verifies we probably watch skinny little towers go up all afternoon that never really establish and the cap wins. I dont know if either of those is typical model biases but something to watch!

I don't know about the Euro but the GFS has a well known capping bias.

 

[Ledian]

Yeah, i'm mostly in monitoring mode for Monday still, but with what i'm seeing, i'm starting to get a little concerned about what i and others around here might be in store for.