Severe WX April 11-14th, 2022 Severe Weather Threat

[OHWX97]

18z HRRR is rather alarming for southern Minnesota/northern Iowa on Tuesday. Dry line is a nonevent.

 

[UK_EF4]

18z HRRR joining the more progressive bunch of models, leaving just ECM and UKMO back with a slightly slower system, with the strongest LLJ exiting Arkansas and surrounding areas by 18z. Environment still looks favourable further North, but large scale synoptic pattern favours a more linear mode. We *may* have dodged a higher-end potential, but we will see.

 

[Fred Gossage]

18z HRRR joining the more progressive bunch of models, leaving just ECM and UKMO back with a slightly slower system, with the strongest LLJ exiting Arkansas and surrounding areas by 18z. Environment still looks favourable further North, but large scale synoptic pattern favours a more linear mode. We *may* have dodged a higher-end potential, but we will see. View attachment 13358

If the surface low occluding wasn't pushing the northern end of the front so quickly so that it would be tucked back westward a little over central Missouri into Arkansas in a more north-to-south orientation, that would still be a trough orientation favorable for a fully discrete storm mode. However, the northern end of that front races eastward on the synoptic level, and that causes the front to be parallel to the deep-layer shear, despite the broad-base nature of the upper trough. You don't get more angled deep-layer shear vectors until you get farther out into the warm sector where the deep-layer shear magnitudes are a good bit too weak to support supercell structures. Yeah, this one definitely looks a lot more scary at first glance than it actually does when you start digging into the details.

And this deep-layer shear orientation/magnitude problem is an issue across all guidance for the most part, not just the HRRR. Deep-layer shear orientation and magnitude are life/death, make-or-break critical to storm mode, no matter what composite parameters, CAPE, and SRH look like.

 

[WesL]

10% hatched tornado probabilities and 30% hatched hail probabilities to compliment the upgrade to ENH over parts of OK and AR today... heads up.

Woooohooooo

 

[South AL Wx]

Tornado Watch issued. 70/40 probs.

 

[TH2002]

Woooohooooo

Looks like Fayetteville lucked out of being included in the Tornado Watch though as everyone knows that doesn't mean zero threat. Stay safe!

 

[TH2002]

Latest GFS SCP sounding from SE OK within the watch area. Unless I'm missing something looks like the cap won't be a huge problem, but I will say with modest shear and a relative lack of diurnal heating today storms may struggle to become surface-based. Only one way to find out though...

 

[Taylor Campbell]

Severe thunderstorm headed towards Fort Smith, AR.

 

[TH2002]

Severe thunderstorm headed towards Fort Smith, AR.

Well... that was fast. It's already trying to rotate too.

 

[MattPetrulli]

Well... that was fast. It's already trying to rotate too.

 

[warneagle]

Stop me if you've heard this one before, but if this thing produces, it's going to pass very close to the Fort Smith radar.

 

[Taylor Campbell]

Tornado warned now.

 

[WesL]

Well south of us in Fayetteville but worth watching as I believe the instability is creeping north.

Meanwhile in Ft. Smith

 

[TH2002]

Speaking of a tornado warned cell moving directly towards a radar site...

 

[WesL]

Speaking of a tornado warned cell moving directly towards a radar site...
View attachment 13361

I kinda like that radar... wish it wouldn't.

 

[WesL]

Spotter reports it is on the ground approaching Ft. Coffee

 

[WesL]

Forth Smith reporting tennis ball sized hail

 

[atrainguy]

 

[TH2002]

Fort Smith's radar is still standing, but past Fort Smith it's definitely making a valiant effort to produce now

 

[Jpgood97]

Classic structure


Sent from my iPhone using Tapatalk