Severe WX Severe Threat 25 March 2021

[eric11]

Considering it's only March, yesterday we may have experienced the strongest March Dixie outbreak since 3/1/2007 or 3/28/1994(Palm Sunday Outbreak),especially given the ridiculous parameters and condition which you won't see it everyday in March either from models or in reality(crazy shear, perfect hodo,stout EML,adequate CAPE).It's unfair to compare yesterday's event to other high end Dixie event for most of these events occurred in mid to late April, which have better heating condition, longer sunshine hours, better moisture and higher integrating degree of wind shear and cape,etc, Needless to say 4/27/11, such an once-in-a-lifetime event.Both SPC and regional NWS called for the right predictions and choices as multiple long track supercells roaring acorss Deep South, BY NO MEANS should this event to be called a "bust" or SPC/NWS to be blamed.
What attracts me most was we've just witnessed two "high-end" event occurred only a week apart,and,it's only March! Whatever these two events was actually verified or not, the crazy parameters and possible massive severe weather outbreak which constantly shown on the CAMs and other long-range forecasting tools were pretty concerning, nonnegligible,and pretty rare under the current time span.As we heading into April with a decaying Modoki La Nina background, I'm sure we about to face more severe weather events for the South, and some of them may perform way stronger than yesterday's event for the better heating and warmer GOM, which is not good news to Dixie alley.

 

[HazardousWx]

SPC products are not really designed for the public, except watches.

 

[Fred Gossage]

Considering it's only March, yesterday we may have experienced the strongest March Dixie outbreak since 3/1/2007 or 3/28/1994(Palm Sunday Outbreak),especially given the ridiculous parameters and condition which you won't see it everyday in March either from models or in reality(crazy shear, perfect hodo,stout EML,adequate CAPE).It's unfair to compare yesterday's event to other high end Dixie event for most of these events occurred in mid to late April, which have better heating condition, longer sunshine hours, better moisture and higher integrating degree of wind shear and cape,etc, Needless to say 4/27/11, such an once-in-a-lifetime event.Both SPC and regional NWS called for the right predictions and choices as multiple long track supercells roaring acorss Deep South, BY NO MEANS should this event to be called a "bust" or SPC/NWS to be blamed.
What attracts me most was we've just witnessed two "high-end" event occurred only a week apart,and,it's only March! Whatever these two events was actually verified or not, the crazy parameters and possible massive severe weather outbreak which constantly shown on the CAMs and other long-range forecasting tools were pretty concerning, nonnegligible,and pretty rare under the current time span.As we heading into April with a decaying Modoki La Nina background, I'm sure we about to face more severe weather events for the South, and some of them may perform way stronger than yesterday's event for the better heating and warmer GOM, which is not good news to Dixie alley.

And in addition to those background things you point out, which we've had a great concern about on this forum for months, is that the MJO looks to cycle back through the Pacific as we head into early April, before the wave collapses again around the middle of the month... similar to what it did over the past 4 weeks or so and similar to what it did ahead of some of these other higher-profile periods, including the one in April ten years ago. That's not, in any remote stretch of the imagination, calling for a repeat of that, but the same mechanisms that got the pattern jump-started for the second half of this month are repeating for likely the second half of April... and prior to that during the first part of the month, we look to develop a -NAO block for a little bit again, which looks to keep the pattern suppressed. That drastically decreases the chances of us ridging out and this shifting north out of Dixie when the active pattern rears its head again deeper into April.

 

[Clancy]

And in addition to those background things you point out, which we've had a great concern about on this forum for months, is that the MJO looks to cycle back through the Pacific as we head into early April, before the wave collapses again around the middle of the month... similar to what it did over the past 4 weeks or so and similar to what it did ahead of some of these other higher-profile periods, including the one in April ten years ago. That's not, in any remote stretch of the imagination, calling for a repeat of that, but the same mechanisms that got the pattern jump-started for the second half of this month are repeating for likely the second half of April... and prior to that during the first part of the month, we look to develop a -NAO block for a little bit again, which looks to keep the pattern suppressed. That drastically decreases the chances of us ridging out and this shifting north out of Dixie when the active pattern rears its head again deeper into April.

Yeah, I was gonna say, we've had this much, and it's not even April.

 

[Austin Dawg]

Yeah, I was gonna say, we've had this much, and it's not even April.

Or May when it shifts towards the plains.

 

[WhirlingWx]

 

[WhirlingWx]

Reminder that these are preliminary ratings

 

[eric11]

Multiple subvortices and satellites, our radar monster behaves pretty close to Bassfield

 

[warneagle]

FFC says Newnan was "at least" EF2.

 

[WhirlingWx]

Video isn't of the best quality but you can see the violent motion and hear the roar

 

[Jacob]

FFC says Newnan was "at least" EF2.

The velocity returns did seem to weaken a decent bit as it moved into town, I was hoping that would indeed be the case on the ground. Not that EF2 or EF3 isn't very serious for all affected, but those returns SW of town screamed something stronger. I'd be curious to see how damage was a few miles SW of town and how it compared to the damage in Newnan itself.

 

[Tennie]

I wonder if their forecast area is too large for current staffing levels? Still, if that's the issue I can't imagine what 6-7 active warnings would've been like in their area...

IIRC, one of the major forecasting issues that was encountered during the tornado that hit Plainfield, IL, on August 29, 1990, was that the Chicago NWS office's CWA at the time covered most of the state of Illinois; this ended up creating a high-workload environment that overwhelmed the people on the job that day, and ultimately by the time a tornado warning was finally issued the tornado had already dissipated.

In the aftermath of that disaster, the Chicago CWA was trimmed back severely (more or less to what it is today), the rest being divvied up anomg other offices (either preexisting or newly created).

Also, during the 1990s NWS modernization the Huntsville office was closed and its CWA was given over to the Birmingham office. However, experiences soon showed that to be a mistake (though thankfully not on the level of Plainfield); and so the Huntsville CWA was reformed in 2002.

I've heard suggestions (typically regarding GA winter storm nowcasts) that the Atlanta CWA should be split into two or even three separate CWAs, in a manner similar to the above two instances. Whether or not that'll ever happen would have to heavily depend on politicking in NOAA and perhaps the rest of the government (federal/state/local). Hopefully, however, something does get done before another disaster occurs due at least in part to overworked staff...

 

[CheeselandSkies]

Video isn't of the best quality but you can see the violent motion and hear the roar

That appears to have been one of the more visible tornadoes from yesterday, as suggested by its more classic radar presentation/cleaner inflow region. Most of yesterday's tornadoes seemed to be your typical Southern low-contrast "whirling fog banks" nearly impossible to discern unless you were dangerously close.

A number of 4/27 tornadoes took on the look of this video, stout wedge beneath a very low-LCL updraft base/wall cloud.

Speaking of which, how close was this to the Sawyerville-Eoline EF3 path from that day? That one missed Brent/Centreville to the northwest (thus hitting Eoline), but yesterday's tracks seemed to get closer to their parallels from 4/27 the further northeast you went (Tuscaloosa/Jefferson getting missed to the south, but Ohatchee to north of Piedmont and into Georgia near Cave Spring getting hit again).

That is one of the less well-remembered tornadoes from that day, despite the fact that it was on the ground for over 70 miles, almost certainly capable of violent-level damage at some point, and killed seven people. The cities of the I-65 corridor south of Birmingham caught a major break when the tornado lifted between West Blocton and Montevallo, and (bucking the trend of that day) the parent supercell did not rapidly cycle and produce another monster. It seems they were not so lucky yesterday.

 

[warneagle]

Newnan is at least high-end EF3.

 

[Gail]

I know that wx is fickle. I respect the SPC and wx forecasters. Honest question. Does the SPC individuals get supervised and graded like most individuals that do with their jobs? I believe the SPC is throwing out moderate and high risks wo even thinking of the consequences. Many people get upset and anxiety when they see a moderate or high risk. Also schools closing and businesses. Daily lives are affected by their outlooks. Also the wording they used yesterday and last week were terrifying. I believe what needs to change is the perception of what each outlook means and when it should be issued. I don’t believe a high risk should be issued until the event is happening. Like issuing a tornado emergency. Moderate to me should be the high risk to issue day of if needed. To me these 2 outlooks should be used for knowing there will be mostly EF3 or stronger tornadoes that day. If the average is going to be closer of having EF0–3 tornadoes then stair step it up. Marginal mostly EF1-2. Enhanced EF1-3. Slight EF0-1. Yes letting public know there could be a stronger one. To me Moderate is used way to much. High risk is joining that thinking. I also think outlooks at 4 days or more needs to stop. 3 should be max. That’s plenty of time to get word out. I mean for real an enhanced already? To me the outlook for tomorrow should be slight and adjusted tonight or early morning if need be.

I’m a federal employee, and we have annual appraisals. That said, it’s based off the entire year and 1-2 days will not stand out. Had the cap over Mississippi degraded like models were projecting, the high risk for MS would have likely panned out.

 

[sak]

You are correct. They are working towards using Threat levels 1,2,3,4,5. You can see this on many NWS graphics packages from yesterday. I am with ya!

And who on earth decided that "enhanced" should be lower on the scale than "moderate"

If you are going to use 5 words to rank the threat levels, they've got that badly wrong.

Marginal
Slight
Enhanced
Moderate
High

compared to, say,

Low
Marginal
Moderate
Enhanced
High

Which do you think the public would see as making more sense?

Or just use 1-5 which is incredibly easy to understand.

I swear half the time a high risk goes up it is because forecasters deep down know that the public won't take "moderate" as seriously as they should. And that is because they named it like a bunch of idiots.

My .02

 

[Equus]

What a day. I see Newnan was as violent as it looked. I await what BMX finds along the massive wedge path later today. Wouldn't be shocked if there's not much above EF2 in the Bham suburbs to Ohatchee tornado unless I missed something significant; I think most of the fatalities were in mobile homes and a lot of the houses heavily damaged looked collapsed or poorly anchored. Guess we find out?

No doubt, if there are DIs for the pre-Newnan tornadoes down in eastern AL, we could have nearly twice the strong tornadoes as last week's event. Quite impressive.

 

[Bamamuscle]

And who on earth decided that "enhanced" should be lower on the scale than "moderate"

If you are going to use 5 words to rank the threat levels, they've got that badly wrong.

Marginal
Slight
Enhanced
Moderate
High

compared to, say,

Low
Marginal
Moderate
Enhanced
High

Which do you think the public would see as making more sense?

Or just use 1-5 which is incredibly easy to understand.

I swear half the time a high risk goes up it is because forecasters deep down know that the public won't take "moderate" as seriously as they should. And that is because they named it like a bunch of idiots.

My .02

I’m a teacher and the verbiage is super confusing. For example most folks don’t understand the word marginal.. In my opinion the public products should only have three risk categories: low, medium, and high. They can differentiate those using the percentages. A lot of what the SPC puts out shouldn’t be available for the general public. That’s just my opinion as an educator tho..


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[warneagle]

The Waynesboro, TN tornado was rated EF2.

 

[TH2002]

Not sure what to make of this damage from Alabama