So tomorrow it looks like we are in the bullseye for a tornado outbreak.
It looks like the atmosphere will be able to recover after the last of the overnight storms exit Northeast Alabama around Daybreak.
And this Ides of March severe weather threat should be from about Noon to Midnight on Saturday.
Tennessee counties are generally under the Enhanced Level 3 out of 5 Risk. Most of North Alabama is under the Moderate Level 4 out of 5 Risk. And - this is rarely issued - much of Central Alabama has actually been upgraded to the High Level 5 out of 5 Risk. That High Risk does clip Southern Cullman County as well as part of Blount County and includes nearly all of Walker and Fayette Counties, also Southern Lamar. It includes Birmingham and Anniston down there.
In that High Risk zone, there is a 30% chance of seeing a tornado within 25 miles of any given point. For most of North Alabama, there is a 15% chance of seeing a tornado within that range. And for Tennessee counties, there is still a 10% chance.
When you're looking at chances of rain, a 10% chance is not even worth worrying about. But for a tornado, it is significant. And certainly a 30% chance of a tornado passing within 25 miles is significant.
All of us, regardless of these risk categories and percentages, are in the hatched area. That means there is a reasonable chance that some of these tornadoes will be stronger than average. We could see some that have to be rated E/F2-F3, or somewhere could even see a tornado worse than that, one of those rare tornadoes that you don't ever want to see, unless you're on a storm chase.
So this is a very serious situation. We haven't had a high-end tornado threat like this since March of 2021.
We had two of them in a row that month, and one event produced mostly regular tornadoes, rated E/F0-F1 and a few E/F-2's. The other one produced several rated E/F-2 or E/F-3.
Let's not get too hung up in nitpicky details about how bad this is going to get, just know that this is toward the upper limit of how volatile the atmosphere gets. On average we see a setup like this every few years. This is serious business this time.
If you have a storm shelter or basement or safe room, you should use it.
Most people don't, and should shelter in a sturdy site-built house or other strong building in a small room (or hallway) on the lowest floor, away from windows and near the center of the building. Put some walls between you and that storm outside. And cover your body, especially your head. Most people who die in tornadoes, it's from head injuries. And something as simple as a safety helmet can save someone's life, even if they take a hit from one of the really damaging tornadoes.
Covering your body with blankets, a pillow, or a small mattress can also work, shield you from falling or flying debris. But a bike or football helmet is the ideal protection against head injuries in these kinds of events.
And you can't stay in a mobile home during a Tornado Warning, especially in an event like this.
One good thing is that the lead time on warnings is likely to be excellent, since are expecting long-tracked supercell thunderstorms out of this. People should have plenty of time to get out of manufactured homes (i.e. trailers) and into a sturdier house or a public shelter after getting a Tornado Warning.
But really, on a day like tomorrow, it might be a good idea, if you live in a mobile home, to go to a safer place and just stay there. Lots of public shelters (all of them in Cullman County, I believe) open as soon as there is a Tornado Watch, and do not wait for a warning to be issued. It's not like you have to do this for every severe weather event, but for one that looks this dangerous, I think I'd get to that safer building or public shelter and just stay there. I've seen people bring sleeping bags or take a nap in a chair in a public shelter before, if they stayed several hours. But this is some serious, life-threatening weather we're talking about. And you can't afford to stay in a mobile home if a tornado is approaching. And instead of driving back and forth on a day like tomorrow, I think I'd just stay in that public shelter, or if you're lucky, a friend or relative's house. And maybe they've got something like a basement. But even if not, a site-built house offers reasonable protection, where a mobile home offers none from this kind of weather.
A mobile home is a death trap during a tornado, especially the really significant kinds we could easily see tomorrow.
If you're driving tomorrow, for work or whatever, plan at least three or four places along your route where you could pull over and get inside, away from windows, preferably in a small space like a bathroom. Or some stores will let people into the cooler if there's a confirmed tornado coming. But you can't get caught in a vehicle either. A tornado will pick that thing up and throw it.
These supercell thunderstorms will also be capable of large hail, up to the size of golfballs, possibly even up to baseball or tennis ball size in some cases. Best chance of that (the 30% area) is places like Florence, Athens, Decatur, Hartselle, Cullman, back to places like Hamilton. Tennessee counties and places like Huntsville, Scottsboro, Fort Payne, Guntersville, Boaz have the basic 15% risk of large hail, but it is still hatched. Meaning it could be really large, like golfball-sized or perhaps even greater. And that too is a reason not to try to drive when one of these storms is approaching. That can knock the glass out of a vehicle and cause serious injury to people sometimes. I had all the glass knocked out of a car one time by a hailstorm, and fortunately I was not in it at the time. It can happen.
The damaging winds in both Alabama and Tennessee could get up to hurricane force, 75 mph or greater.
So even Severe Thunderstorm Warnings tomorrow may be more serious than usual. And if they carry a "Particularly Dangerous Situation" tag, people will actually get them on cell phones. Usually you have to have a weather radio to get your attention for those. Lots of TV stations basically ignore them or just run something across the screen.
Tomorrow is a dangerous day though, and the main concern, frankly, is going to be tornadoes. We may see several of them from this event, and at least one or two could be particularly damaging.
So you've got to do the right things if you fall under a Tornado Warning polygon tomorrow (or even tonight, the first round that I've already posted about). This is nothing to fool around with. Tomorrow is one of those days when making the right decisions about these storms could be the difference between life and death.
And while I'm on a roll, I want to address something that used to always bother me. Some people I knew even as a kid would say that they didn't worry about tornadoes because, "When the Lord's ready to take me, I'll go!" That sounds good, but the reality is that not everybody who suffers a gruesome injury in a tornado dies from it. One the analog events that has kept coming up for this was April 8, 1998. There was a family that lost their son in an F-5 tornado that night near Birmingham, in Oak Grove. He did not survive. (And by the way, the doctors said he probably would have, if he'd had something over his head like a helmet.) But the rest of that family did. And his father was put in a wheelchair because of his injuries. He had to attend the funeral in a wheelchair, I believe. And come on, would you wish that on anybody you know? It's not like the movies. You don't get blown away to Munchkinland. When someone is seriously injured in a tornado, whether they make it or not, it is some ugly, brutal stuff that you don't ever want to have to see. And that's why it's important to pay attention to the warnings and take the best shelter that is within your means.
A lot of people probably wish they had a storm shelter or basement, but don't. And I can't remember who says this on the Weatherbrains podcast, whether it's Troy Kimmel or Kim Klockow-McClain. But somebody on there often says: Just because you can't have a perfect plan, don't let that stop you from using a plan that is good enough.
Somewhere between 90-99% of the time, if you shelter in a sturdy site-built house in that lowest, most central small room or hallway, away from windows, you're going to make it. With an event like this, I'd hope people had some head protection too. The main thing is getting people out of mobile homes and into a sturdier house or other building.
Having said that, this is one of those events where if you do have a proper storm shelter, you should definitely use it. Don't rely on luck. If you can get underground or in one of those FEMA-certified shelter rooms, then by all means, get in there, and you'll be just fine. The reason I recommend all this other stuff is that most people do not have access to that near their home. I've never heard of anyone dying from a tornado in one of those old-fashioned storm cellars. I saw it in the original Twister movie, but in real life, that's as safe as you can be.
And this is one of those events like we haven't had in a long time, where the concern is just saving lives. We certainly could have loss of life if people don't get the warnings or are not able to get to a good safe place in enough time. Before we had the National Weather Service (originally was called the Weather Bureau), news of a tornado coming was by word of mouth, and it was common for people to die from them. With all the technology, communications, and in some places even public shelters that we've got now, we should be able to minimize that death toll. And in a lot of events, we can save everybody. Even in those two outbreaks in March 2021, the best I recall, the fatalities were in mobile homes. So that's the reason for all this driving the point home and talking about safety. For meteorologists or for storm spotters (like me, I'm a storm spotter who never completed a meteorology degree), it is a really sick feeling to see where someone got killed or seriously maimed in a tornado or other severe storm. Especially if you know it could have been easily prevented. When it happens in mobile homes, that gets depressing to see after a while. And when we get through a tornado outbreak or even a damaging wind event without any loss of life, that sure does feel like a win. Like the science is paying off.
So anyway, take good care of yourselves. And try not to get too unnerved by this stuff. The odds are very much in your favor if you do what you know you should do after you get a Tornado Warning.
SPC AC 141730
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 PM CDT Fri Mar 14 2025
Valid 151200Z - 161200Z
...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS IN CENTRAL/SOUTHERN
PARTS OF MS/AL...
...SUMMARY...
A tornado outbreak is likely on Saturday across the central Gulf
Coast States and Deep South into the Tennessee Valley. Numerous
significant tornadoes, some of which should be long-track and
potentially violent, are expected on Saturday afternoon and evening.
The most dangerous tornado threat should begin across eastern
Louisiana and Mississippi during the late morning to afternoon,
spread across Alabama late day into the evening, and reach western
parts of the Florida Panhandle and Georgia Saturday night.
...Central Gulf Coast/Deep South/TN Valley...
After collaboration with WFOs BMX/JAN/MOB, an upgrade to a level
5-HIGH risk appears warranted for the most likely corridor of
potentially violent tornadoes, peaking tomorrow afternoon and
evening. A broader level 4-MDT risk has been expanded somewhat
eastward for the nocturnal significant tornado threat.
An intense mid-level jet, 100-110 kts at 500 mb, will eject through
the basal portion of a broad southern Great Plains shortwave trough.
This will induce secondary cyclogenesis along an initially
slow-moving baroclinic zone from the Ark-La-Tex to the central Great
Lakes. Another day of air mass modification ahead of this wave will
yield a pronounced plume of rich northwest Gulf moisture that should
be pristine across southeast LA and southern MS through late
morning. As mid-level height falls overspread the diurnally warming
air mass, increasing convective development is expected along the
deepening baroclinic zone, as well as residual outflows to its
northeast in the TN Valley from prior late D1 convection.
Steep mid-level lapse rates atop the richly moist boundary layer
will yield at least moderate MLCAPE from 1500-2500 J/kg across
eastern LA into central MS. Vertically veering wind profiles with
strong anvil-level divergence amid the favorable instability should
support robust updrafts and intense supercells. Low-level shear will
strengthen midday through the afternoon, yielding potential for a
tornado outbreak.
The most probable convective corridor will be along the effective
outflow boundary across central/northern parts of MS into north AL
and south TN. Along and south of this will be the most favored
corridor for long-tracked, discrete supercells. These will likely
develop within north/south-oriented confluence bands as increasing
large-scale ascent becomes coincident with the peak heating cycle.
A volatile combination of kinematic/thermodynamic parameters will
support potential for long-track, EF3+ tornadoes. The overall
spatial extent of this threat will be modulated by the degree of
boundary-layer heating within the mid to upper 60s dew point plume,
along with where exactly the large-scale outflow boundary sets up
from late D1/early D2.
Significant tornado potential, along with very large hail and
destructive damaging wind gusts, should persist into Saturday night.
Greater potential for a broken to linear band of thunderstorms is
anticipated by this time, but wind profiles will still strongly
favor supercells. As such, a mix of all three hazards may continue
with sig severe hail potential favored south and sig severe wind
favored north as the convective band spreads towards the southern
Appalachians and the northeast Gulf Coast.
...OH Valley to central Great Lakes...
Forecast confidence remains low with regard to severe potential
north of the TN Valley. Guidance continues to differ on the degree
of diurnal destabilization in the wake of the D1 shortwave trough
and deep cyclone tracking into northern Ontario. With increasingly
widespread Mid/Deep South to TN Valley thunderstorms during the day
Saturday, the northward extent of appreciable surface-based
instability appears highly questionable within a predominately
meridional deep-layer wind profile. Given the fast flow regime
though, even weak convection late afternoon through Saturday night
will pose some risk for locally strong gusts and a tornado.
..Grams.. 03/14/2025
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