Severe WX Severe Threat 17-18 March 2021

[Brice]

Of particular interest is the boundary-layer moisture that is now
present along the Gulf Coast where lower 70s surface dew points are
observed. This air mass will advance north during the day and
diurnal heating will allow moderate instability to develop along a
corridor from southern LA through central MS into western AL where
SBCAPE should be on the order of 2500 J/kg. While the primary 500mb
speed max will likely maintain convection along the surging Pacific
front over southeast TX, an uncapped, buoyant air mass downstream
over MS/AL should prove favorable for discrete supercell development
ahead of the primary short wave. Forecast soundings across the HIGH
Risk exhibit profiles favorable for strong, long-track tornadoes,
and this is especially true from northeast LA through norther

 

[Casuarina Head]

Day 2 went MDT with 15% hatched TOR

 

[WhirlingWx]

Thursday just went moderate risk as well.
Edit: ninja'd again

 

[Fred Gossage]

Don't be surprised if the High Risk is expanded farther across north central Alabama in coming outlooks. High resolution guidance continues to trend more ominously for north and central Alabama as early as mid afternoon with the open warm sector stuff. This may extend as far north as far southern middle TN.

 

[Brice]

Thursday just went moderate risk as well.
Edit: ninja'd again

Never gonna end

 

[sak]

I am curious to see how this all plays out across Alabama. The high res models are outputting discrete supercells forming by 2-4pm... but it seems like the worst of the dynamics might still be over in LA/MS at that point. Then when the main dynamics do arrive, we might be looking a more of a linear line coming through overnight.

Thoughts?

 

[Equus]

As always, don't forget to fill in the radar hole in NE LA with KULM radar from Monroe.

 

[Casuarina Head]

Don't be surprised if the High Risk is expanded farther across north central Alabama in coming outlooks. High resolution guidance continues to trend more ominously for north and central Alabama as early as mid afternoon with the open warm sector stuff. This may extend as far north as far southern middle TN.

Is the secondary line looking to be less discrete than on earlier runs? It seems the trend is toward warm-sector development ahead of it.

 

[Austin Dawg]

Don't be surprised if the High Risk is expanded farther across north central Alabama in coming outlooks. High resolution guidance continues to trend more ominously for north and central Alabama as early as mid afternoon with the open warm sector stuff. This may extend as far north as far southern middle TN.

Started tonight.

 

[Equus]

Yeesh, 5z HRRR definitely explicitly showing nastiness in the warm sector. Definitely see an expansion coming further to the east imo

 

[CSimonds]

E

I remember feeling this way last Easter when the dewpoints were in the 40s the night before but we still had forecast severe weather the next day. When the warm front moved thru the airmass changed almost instantly, although maybe the amount of advection required did keep the outbreak from being even worse.

the winds in NE AL switched from the SSE to ENE

 

[Casie]

Good history here to give depth and importance to the High Risk. https://en.wikipedia.org/wiki/List_of_Storm_Prediction_Center_high_risk_days#2020–present

 

[Brice]

Good history here to give depth and importance to the High Risk. https://en.wikipedia.org/wiki/List_of_Storm_Prediction_Center_high_risk_days#2020–present

Always a fun site to look at

 

[Equus]

05z HRRR doesn't look like a fun ride

 

[Brice]

05z HRRR doesn't look like a fun ride

View attachment 7012

I don't like that at all

 

[Jpgood97]

Nasty cell that cuts through Tuscaloosa

 

[Brice]

Nasty cell that cuts through Tuscaloosa

Hopefully that doesn't become accurate

 

[Snowyfbaby]

For what this is worth and take with a grain of salt but a few hours ago at 10 pm central near Birmingham I flew my drone about a mile out and stayed between 220feet to 400ft and it was not raining by the way very muggy atmosphere but I was not expecting this by the time I flew her home (dji mini 2) she was purely stacked with water I’m shocked it stayed in the air I just wanted to leave that example that only 200-400 feet up our dew point has to be absolutely the highest I’ve ever seen my fly app said it was ok to fly and I was outside a few minutes before I flew and didn’t think anything of it and by the time it landed back home i had to run it inside turn wipe it off quickly and just left the blades on for 20 minutes to try to dry just wanted all you to know how soupy it is right now and this is in Walker county Alabama

 

[Brice]

For what this is worth and take with a grain of salt but a few hours ago at 10 pm central near Birmingham I flew my drone about a mile out and stayed between 220feet to 400ft and it was not raining by the way very muggy atmosphere but I was not expecting this by the time I flew her home (dji mini 2) she was purely stacked with water I’m shocked it stayed in the air I just wanted to leave that example that only 200-400 feet up our dew point has to be absolutely the highest I’ve ever seen my fly app said it was ok to fly and I was outside a few minutes before I flew and didn’t think anything of it and by the time it landed back home i had to run it inside turn wipe it off quickly and just left the blades on for 20 minutes to try to dry just wanted all you to know how soupy it is right now and this is in Walker county Alabama

Wow be weather aware

 

[Snowyfbaby]

Wow be weather aware

Yea probably wasn’t the best time to fly to be honest and at around 370 feet I did get a high wind warning so things are a moving up there but on the ground it wasn’t that way.