Severe WX Severe Weather Threat 3/14-3/16

[The Nino]

as we are getting closer, what are the things to watch for that could throw a wrench in this? So far it seems to be not much in the way of this system and is high ceiling.

 

[Bamamuscle]

I was discussing the weekend threat with my students and they informed me that one of the high schools did not reschedule their prom on Friday night. Were in N AL.. Isn’t there a risk of storms Friday night here too?

 

[Fred Gossage]

as we are getting closer, what are the things to watch for that could throw a wrench in this? So far it seems to be not much in the way of this system and is high ceiling.

How capping does or does not hold from before daybreak through the morning and how widespread any storms are and whether they try to linger to work over the environment. Unfortunately, you're just not going to catch a 2023-2025 era CAM that will handle a EML cap correctly outside of 24 hours, and some of them won't even do it within 12 hours with the actual upper air data sampling the cap upstream.

 

[Fred Gossage]

I was discussing the weekend threat with my students and they informed me that one of the high schools did not reschedule their prom on Friday night. Were in N AL.. Isn’t there a risk of storms Friday night here too?

Yes, 2/5 for Madison County and sigtor driven 3/5 from I-65 west for the late night to daybreak.

 

[Clancy]

I was discussing the weekend threat with my students and they informed me that one of the high schools did not reschedule their prom on Friday night. Were in N AL.. Isn’t there a risk of storms Friday night here too?

Yes. Looks like a late night problem, so how much it impacts the prom depends on how late it goes. Either way, they need to be on watch.

 

[jiharris0220]

FV3 tends to overcook things in going all in on discrete supercell modes but still. This is not the ceiling we would want to transpire.

This is to simply highlight what the worst case scenario could look like, while the 3km resolution NAM would actually be one of the better scenarios to play out.

 

[Tomcats Forever!]

FV3 tends to overcook things in going all in on discrete supercell modes but still. This is not the ceiling we would want to transpire.

This is to simply highlight what the worst case scenario could look like, while the 3km resolution NAM would actually be one of the better scenarios to play out.
View attachment 35299

Paints an S.O. Not buying it.

 

[Clancy]

As much as the FV3 is a trigger-happy supercell printer, I think it might not be too off-base with regard to Friday night and it is a good visual for what convective evolution might look like. Probably a bit more linear, but I think it's onto something.

 

[RollTide18]

I’d do anything for this event to Forecasted Convective Amplification Deficiency, looks pretty bad

Setups are very different but getting March 1, 2007 vibes in terms of areas covered

 

[MichelleH]

Yes. Looks like a late night problem, so how much it impacts the prom depends on how late it goes. Either way, they need to be on watch.

Problem will be prom parties and a bunch of drunk teenagers not paying attention to the weather.

 

[Maxis_s]

As much as the FV3 is a trigger-happy supercell printer, I think it might not be too off-base with regard to Friday night and it is a good visual for what convective evolution might look like. Probably a bit more linear, but I think it's onto something.
View attachment 35300

That's Friday morning.

 

[Clancy]

I’d do anything for this event to Forecasted Convective Amplification Deficiency, looks pretty bad

Yep, a lot of us in the same boat.

Problem will be prom parties and a bunch of drunk teenagers not paying attention to the weather.

Yeah, and when they have any kind of event going on, it's already harder to get them to listen.

 

[Clancy]

That's Friday morning.

Friday night into Saturday morning, focusing on the initiation of convection over ArkLaMiss into AL.

 

[ColdFront]

That's Friday morning.

No it’s not. It’s animating into Saturday morning

 

[Maxis_s]

Friday night into Saturday morning, focusing on the initiation of convection over ArkLaMiss into AL.

For some reason I thought you meant it was Saturday night, and then tried to correct you and was even more wrong lol

 

[Bamamuscle]

Yes. Looks like a late night problem, so how much it impacts the prom depends on how late it goes. Either way, they need to be on watch.

I can see a bunch of 17-18 year olds driving around at 1-2am. I’m terrified.

 

[CheeselandSkies]

Both HRW WRF models suggest southeast MO into southern IL (basically St. Louis area southward to the IL-KY line) might actually have the roughest time Friday night. As an addendum to my previous, after ignoring them for a long time (mainly because they can't resolve smaller-scale supercells like the HRRR can, at least in theory), they're probably as good as any CAM.

 

[Maxis_s]

James Spann mentioning the possibility of violent, long-tracked tornadoes.

 

[drscottsmith]

....we've seen upgrades to the RAP, the HRRR, the GFS, and the Euro change parameterizations and other things that may help them score better on the verification stats for something like 500mb heights, but it's been a significant detriment to their ability to handle the reality of things like cap strength, convective initiation and coverage, boundary layer moisture vs mixing, low-level wind response to pressure and height falls, and all these other things that are life and death critical to accurate severe weather forecasting.

Fred - it seems almost as if this was in some ways a bad trade off...is there more to it (like future return to a more comprehensive system)?

 

[Fred Gossage]

....we've seen upgrades to the RAP, the HRRR, the GFS, and the Euro change parameterizations and other things that may help them score better on the verification stats for something like 500mb heights, but it's been a significant detriment to their ability to handle the reality of things like cap strength, convective initiation and coverage, boundary layer moisture vs mixing, low-level wind response to pressure and height falls, and all these other things that are life and death critical to accurate severe weather forecasting.

Fred - it seems almost as if this was in some ways a bad trade off...is there more to it (like future return to a more comprehensive system)?

I think most to all of it is unintentional and just the chaotic nature of the atmosphere.