Severe WX March 29-30, 2022 Severe Event

[DetectiveWX]

Oh, I'll bite. Sure looks like a significant severe weather outbreak is onboard from TX into the Deep South next Tue/Wed, with a potentially more dangerous one on the Super '74 48th anniversary. La Nina is truly showing her hand I'm afraid...

 

[Taylor Campbell]

GFS lines up the instability and shear, but the EURO has the best dynamics out running the instability. The ensembles aren't overly impressive. Again, not quite like our past event in terms of the type of agreement we had for it.

 

[CheeselandSkies]

Looks like another bullseye on LA/MS for next Wednesday. Still a lot of time for things change. 12Z GFS, the trough looks a little broader (not as squashed E-W), still pretty meridional though but with a pronounced split (diffluence) in the exit region of the jet streak. Moist sector is quite large (upper 50s dews all the way to 43 degrees north), and as usual the SBCAPE map makes little sense in comparison.

 

[MattPetrulli]

For Tuesday, while parameters look good and latest run of CIPS analogs is kind of excited about it, both global models hint at capping. GFS especially also is kind of moisture starved for that day, if moisture trends up and CAP/CIN trends down could see a good day but kind of uncertain

Wednesday reminds me of last Tuesday from last event, may also see the same issues as we saw with last event but I think that's really the day to watch. Something that is present Wednesday that last Tuesday didn't have is plentiful moisture return, though Tuesday had deeper moisture if I believe, all the way to KY. Though Tuesday had deeper moisture if I believe, can easily see that trend up with mesoscale models.

Obviously would like to see deeper moisture for a more significant severe/tornado threat but definitely could be a widespread severe day at least.

At least would likely be another high shear/low CAPE setup.

 

[MichelleH]

Spann is already mentioning next week.

 

[UK_EF4]

Judging from current models, with a very strong low-level jet, shear really shouldn't be a problem, but like some others have mentioned, it looks like one thing to watch for could be best shear outpacing best moisture/thermodynamics.



Definitely needs watching regardless.

 

[tennessee storm chaser]

Based off the 12zeuro, moisture return seems be increasing … healthy warm sector out ahead of the front should be much problem for efficient instability … wind fields are very impressive with this system Wednesday… and with the amount of low level shear present , getting concerned of discrete activity out ahead the main line. For the greater Memphis area looks like early evening to overnight since system seems slower on latest runs . Highly expect spc will add 30 percent severe probs by end this weekend .

 

[CheeselandSkies]

On the GFS the trough seems to be gradually trending slightly less meridional with time (18Z a little less so than the 12Z and 12Z a little less than the 06Z...looking at the FH valid for 21Z on Wednesday the 30th)...if that keeps up and the model is underdoing the instability across most of that large moist sector with gnarly hodographs...yikes.

 

[UK_EF4]

Looks like the SPC included 30% probabilities for Wednesday

 

[Casuarina Head]

The 00Z EPS suggests more of a strongly forced line or QLCS than it does discrete activity, given meridional forcing and relatively low instability across most of the warm sector, save near the line. The twin polar vortices (Aleutian and Greenland lows) trend deeper on the latest suite and reinforce high-latitude blocking, leading to a rather “pinched-off” trough axis on Wednesday, owing to higher amplitude and shorter wavelength. The question is whether there could still be a threat of severe winds, which is quite possible. But the high-end tornado threat certainly looks to be relatively limited, like the threat of large hail.

 

[UK_EF4]

To be honest, I'm not sure if there is even a question of strong winds - 100+kt 500mb flow and 60-70+ 850mb flow with a strongly forced boundary, but I would agree the threat of a unstable open warm sector with high discrete storm potential isn't quite there at the moment, though things always could change. With a possibly active next few weeks its definitely possible a system more conducive to discrete cells etc could come eventually.. but I hope not.

 

[tennessee storm chaser]

To be honest, I'm not sure if there is even a question of strong winds - 100+kt 500mb flow and 60-70+ 850mb flow with a strongly forced boundary, but I would agree the threat of a unstable open warm sector with high discrete storm potential isn't quite there at the moment, though things always could change. With a possibly active next few weeks its definitely possible a system more conducive to discrete cells etc could come eventually.. but I hope not.

Things look ripe for a large major outbreak for sure , think our time is about up on lesser events we have seen last few years. Spring just started also . Just hang on. Some say global warming could be off setting things , I think it just will increase threats along the intensity of them. Seems like it goes on 10 year intervals . And 10 years is about up. This should been posted over in severe 2022 thread I guess. I apologize.

 

[UK_EF4]

The 12z UKMET indicate that this upcoming system is in no way something to ignore: Rich 65-70F Dew Points up into Louisiana in conjunction with 60-70ky LLJ and a somewhat more zonal flow.

 

[Taylor Campbell]

On the GFS the trough seems to be gradually trending slightly less meridional with time (18Z a little less so than the 12Z and 12Z a little less than the 06Z...looking at the FH valid for 21Z on Wednesday the 30th)...if that keeps up and the model is underdoing the instability across most of that large moist sector with gnarly hodographs...yikes.

Yes, the GFS is trending with a more organized threat.

1PM central time



4PM central time

 

[Fred Gossage]

I still think it's probably mostly linear, but I could easily see this being a QLCS that verifies an ENH+ for widespread wind damage, and I'd expect there to be several tornadoes, even if the only convective feature is the line alone. This won't be end of the world or anything by any means, but I don't expect this to be an isolated or low-end event, even if there's not a single discrete storm ahead of the line. I'm not quite sure yet that it will pull it off, but the idea of a possible serial derecho has been in my mind the past couple of days.

 

[UK_EF4]

This is a question for someone with more knowledge than me... but is model output regarding moisture return a but suspicious/doesn't make sense?
With very strong southerly winds coming right off the gulf, I would expect much more significant moisture return than being modelled, with an area of 60-65F dew points for only a small section of the warm sector. Is this a realistic representation or is it likely it would be more than currently modelled? Especially with southerly flow preceding this for about 1-2 days beforehand, but moisture never really builds properly. Any ideas?

 

[Fred Gossage]

That's going to be a legitimate concern. The troughing we have over the East this weekend pushes the deeper moisture south. We recover lowest-level moisture QUICKLY across the Gulf, but the first push or two inland is not going to be that deep. That's going to mean there will be mixing in the warm sector during the daytime. We do get a last minute surge of boundary layer moisture that extends up to or above 850mb right ahead of the QLCS, because we get deeper moisture to surge north out of the Caribbean into the Gulf at the same time the more shallow initial moisture return surges inland from the Gulf Tuesday into Wednesday, but yes, there will be mixing in the warm sector until the final surge of moisture just ahead of the QLCS. The Euro, UKMET, and Canadian may be overdoing it, but you may see dewpoints drop out of the 60s into the 50s Wednesday morning before the surge just ahead of the QLCS gets them back into the 62-66 range.

 

[UK_EF4]

That's going to be a legitimate concern. The troughing we have over the East this weekend pushes the deeper moisture south. We recover lowest-level moisture QUICKLY across the Gulf, but the first push or two inland is not going to be that deep. That's going to mean there will be mixing in the warm sector during the daytime. We do get a last minute surge of boundary layer moisture that extends up to or above 850mb right ahead of the QLCS, because we get deeper moisture to surge north out of the Caribbean into the Gulf at the same time the more shallow initial moisture return surges inland from the Gulf Tuesday into Wednesday, but yes, there will be mixing in the warm sector until the final surge of moisture just ahead of the QLCS. The Euro, UKMET, and Canadian may be overdoing it, but you may see dewpoints drop out of the 60s into the 50s Wednesday morning before the surge just ahead of the QLCS gets them back into the 62-66 range.

Thanks! Makes sense I guess with those 80F temperatures modelled.

 

[JPWX]

The 00z and 12z Euro precipitation suggests more broken line than solid.

 

[Austin Dawg]

I still think it's probably mostly linear, but I could easily see this being a QLCS that verifies an ENH+ for widespread wind damage, and I'd expect there to be several tornadoes, even if the only convective feature is the line alone. This won't be end of the world or anything by any means, but I don't expect this to be an isolated or low-end event, even if there's not a single discrete storm ahead of the line. I'm not quite sure yet that it will pull it off, but the idea of a possible serial derecho has been in my mind the past couple of days.

I fully remember when I lived in Mississippi having experienced QLCS bowed lines that were nothing to sneeze at Derecho level or not.