Severe WX Severe Threat 17-18 March 2021

[Richardjacks]

HRRR really wanting to keep that wedge in place, but yet it's showing some notable cells during the evening round well beyond the extent of the wedge as well as this little guy during the morning stuff. Thoughts?
View attachment 7002

I believe that is elevated...so would have little tornado threat...if the wedge is truly like that

 

[KoD]

Ok, since I'm not an expert...What is a wedge?

"Cold-air damming occurs when cold dense air becomes wedged (hence the term "the wedge") against the windward side of the Appalachian Mountain chain. This shallow, but dense, pool of cold air will sink to the south and west, unable to pass over the mountains themselves due to the height of the mountains. Those on the eastern side of the mountain chain get entrenched in cool and dry air while those on the west side don't get nearly the impacts the east sees from CAD."
Taken from WPDE

 

[Clancy]

I believe that is elevated...so would have little tornado threat...if the wedge is truly like that

Got it, thanks!

 

[NorthGaWeather]

right, I got think it is overdone....just doesn't seem realistic unless we had a whole bunch of rain falling over the front through the morning...that limits the northward movement, but no sign of that

I agree. We have no high that is strongly reinforcing cold/dry air into the region or steady rainfall like you mentioned. I haven't really jumped into mesoanalysis today, but I'd bet it is pretty shallow in depth.

 

[MattPetrulli]

Semi-discrete storm mode and that's violent tornadoes 101 right there.

 

[LP98]

Are these possible tornadoes that Brad Travis says may be happening in the early morning hours? Goodness. Also...I’m new...no weather background, just an anxious worrier. Been lurking here for years. Thanks for having me. Live in SE Huntsville.

 

[Gail]

He’s our state’s public commissioner.

 

[HazardousWx]

Are these possible tornadoes that Brad Travis says may be happening in the early morning hours? Goodness. Also...I’m new...no weather background, just an anxious worrier. Been lurking here for years. Thanks for having me. Live in SE Huntsville.

Welcome. I joined in 2002, I think.

 

[darkskys25]

Semi-discrete storm mode and that's violent tornadoes 101 right th

Semi-discrete storm mode and that's violent tornadoes 101 right there.

Im not exactly sure where this is other than somewhere in ms but look at that srh value. Wow!

 

[Richardjacks]

I will say the wedge fits March climatologically, I can remember many wedges that Atmospheric Anti-Climax severe weather forecasts over the years in March....but I am NOT expecting that to happen this time...

 

[Richardjacks]

0z nam has the wedge retreating a little faster tomorrow afternoon. Bham's Td bounces back up quicker

 

[tennessee storm chaser]

0z HRRR wedge is scrong

got to be a outlier for now... would think

 

[warneagle]

Are these possible tornadoes that Brad Travis says may be happening in the early morning hours? Goodness. Also...I’m new...no weather background, just an anxious worrier. Been lurking here for years. Thanks for having me. Live in SE Huntsville.

There's likely to be an overnight tornado risk in Alabama tomorrow night into Thursday morning, yes.

 

[Richardjacks]

Has anyone seen a discreet supercell? I know, it isn't a CAM

 

[Kory]

Unsure of why there's all this CAD talk. Once those low-level winds kick in, there's a very high octane airmass that will lift north quickly.

 

[Jpgood97]

What is the consensus on the overall risk for say Decatur/Huntsville vs AL/MS state line around Iuka? Is there a noticeable drop off from the state line to North Central Alabama? Or would they all be viewed in the same threshold

 

[Rhartley91]

0z nam has the wedge retreating a little faster tomorrow afternoon. Bham's Td bounces back up quicker

What does this mean for Bham? What time frame should we begin to worry?

 

[Richardjacks]

Unsure of why there's all this CAD talk. Once those low-level winds kick in, there's a very high octane airmass that will lift north quickly.

I guess I am having trouble understanding why the NAM/HRRR is so strong with it.

 

[TornadoFan]

So any bets on whether we get a high risk tonight?

 

[Richardjacks]

What does this mean for Bham? What time frame should we begin to worry?

As soon as the warm front passes through, that is what the models are struggling with tonight...could be late morning, could be mid afternoon..probably morning.