It's two days in the future now, and this is continuing to look like it could be a full-blown tornado outbreak on Saturday, affecting many states, but unfortunately, looks like our number has come up in the Tennessee Valley to be in the core of some of the worst weather this time.
In North Alabama we have a 30% hatched area for severe weather, which is bad enough. This a 30% risk for supercell thunderstorms capable of tornadoes, damaging winds, and very large hail.
But that 45% risk area that covers Birmingham, Montgomery, to Jackson (MS), all the way down to New Orleans, is something that frankly, you don't ever want to see, unless you're a skilled storm chaser. That's basically saying there's a 50/50 chance of having a supercell thunderstorm within 25 miles of a given point, and in this case, those supercells could produce tornadoes - maybe the particularly damaging kind.
And frankly all within the hatched area, so that includes the Tennessee Valley, there is a reasonable chance of seeing tornadoes that would have to be rated at least E/F-2. So that means a strong enough tornado to completely destroy a mobile home, and at least tear the roofing off a well-built house, maybe do further damage. This is one of those setups where especially in Central and South Alabama, back into Mississippi, you have to prepare for the worst and hope for the best. It sort of reminds me of those two tornado outbreaks we had in March back to back in (I think) the year 2021. This looks like it could be a serious tornado outbreak for whoever gets the worst of it. The probabilities are looking higher farther South and West, but none of us need to let our guard down. This has the potential to be one of those full-blown outbreaks, where anybody who gets hit is going to remember it from then on.
Our last two severe weather events were marginal, even if one (back in February) produced widespread power outages and a good bit of tree damage. But this is NOT a marginal situation. This is a high-end risk for supercell thunderstorms capable of producing significant tornado damage in addition to damage from really large hail and severe thunderstorm winds. Everybody needs to take this event really seriously.
Some of the analogs that keep showing up are January 30, 2013 and more worryingly, April 8, 1998. When an event produced an F-5 tornado that killed 30 or so people, it will stick in your memory, even if there were only a few other tornadoes (locally) out of the event. Another analog event that is showing up now, and I think I've seen before in the past few days as an analog, is April 11, 2013. Like many of the other analog events, that one wasn't overly impressive around here. It produced a couple of regular-strength tornadoes but mostly damaging winds and some hail reports across the area. That's still dangerous, but it was nothing like April 1998. The April 1, 2016 event where a tornado hit near Hartselle and Priceville (rated E/F-2) is showing up as an analog. And even though it's at the bottom of the list of top 15 events that came from a similar setup, the Super Tuesday Outbreak of 2008 has shown up as an analog now. There were two E/F-4 tornadoes in North Alabama from that event, and there were several tornadoes in Tennessee too. I remember Nashville had a close call with a supercell thunderstorm that produced an E/F-2 tornado as it approached Davidson County, then produced another tornado Northeast of there which was rated E/F-3.
So taking everything into account, the atmospheric setup, the risk areas defined by SPC here, and similar events in the past, this looks like a tornado outbreak that has the potential for significant impacts to whoever gets hit hardest. This could be one of those events people remember for a long time. Even if it's just one really damaging tornado, or maybe one that hits a city or something . . . not only my logic but my instincts here are telling me . . . this does not look good.
And folks in Jasper, Fayette, over to places in Lamar County like Vernon and Sulligent, are included in that highest-risk area where it's basically a 50/50 shot of getting a supercell that could easily produce a long-tracked, particularly damaging tornado. But all of us are under the 30% risk for supercell thunderstorms capable of producing tornadoes (and yes, could be significant tornadoes capable of more than the usual damage). And that's certainly bad enough.
So if you have a storm shelter, basement, or safe room, you're in really good shape for this event.
Most people don't and will be sheltering in a site-built house or other sturdy building like an apartment. In there, you have to go to the lowest floor. Get into a small room (or hallway) near the center of the building, well away from any windows or doors that lead to the outside. And cover your body in some way, especially your head.
If you have a safety helmet, that's ideal, but things like pillows, blankets, even a small mattress, can shield your body from debris that could fall into your shelter room or go flying in the winds if a window blows out. And most tornado deaths happen because of people getting hit in the head and neck with debris. Sometimes protecting someone's head can save a life. This is an event where some people may need these maximum precautions. If you have something like an air horn, take it to your shelter so you can let emergency workers know where to find you. We hope it doesn't happen, but sometimes people get trapped by debris. If you've got boots or shoes with hard soles, you might wear those to your shelter if you have time to think about it, because after a tornado, people can go into a state of mental shock similar to after a car wreck. You might not realize you're stepping on sharp stuff if you come out looking for help. These are lessons learned from the superoutbreak of 2011. We're not dealing with that kind of an event, but this is looking bad enough that some people may really need to take these extra precautions. They could save a life or reduce the amount of injury someone suffers.
DO NOT STAY IN A MOBILE HOME IF YOU GET A TORNADO WARNING DURING THIS EVENT. Even if you got grazed by a tornado in a setup like this in a mobile home, your chances of survival would be slim to none. So plan ahead to be in a sturdier building by the time a storm producing a tornado gets to you.
As a last resort, if no shelter is available, you could lie in an unflooded culvert or ditch, or even flat on the ground, covering your head and neck with your hands. It may sound like it wouldn't work, but I remember a story from Mount Hope (or nearby) where an elderly couple did abandon a mobile home which was destroyed by an E/F-5 tornado, and they survived in a ditch nearby. So that's not just something we say without evidence to back it up. People have survived this way. Of course if you can, you want to plan ahead so you can make it to a sturdy building in enough time.
If you'll be driving Saturday, plan at least three or four places along your route where you could get inside some sturdy building and take shelter if need be. It doesn't have to be a grocery store or restaurant made out of brick with a steel-reinforced cooler. If all you've got nearby is a gas station, that is better than getting caught in a car. With an event like this, a car is probably as dangerous to stay in as a mobile home. Even though in some of the lower-end events, people like to debate whether a car is slightly safer. With this setup, I'm telling you: Get out of a car or a mobile home before a tornado is bearing down on you, if you value your life. You really need to shelter in a sturdy house or other strong building. And in there, you need to do the right things.
Even if you're in a basement, it makes sense to follow the other ideas like staying away from any windows. And again, in case any debris were to fall from upstairs, it's a good idea to get up under something sturdy if you can - desk, table, workbench, stairs, whatever is there. And it wouldn't hurt to cover your head in some way too. It's pretty rare for debris to get blown into a basement if it's mostly underground, but a lot of basements have a lot of it that's not under the ground. And something like a tree falling in there or a window breaking out on the other end of the basement could cause an injury. I'd rather be overly cautious than not cautious enough. This is serious business this time. This is a high-end threat for severe thunderstorms and tornadoes.
And if you end up under a warning polygon, you're going to have to take a deep breath and do the right things. Like the magician David Copperfield used to say when he did escapes, being scared can be good, if it keeps you on your toes and remembering what you have to do. Panicking is the worst thing you can do. In his case, I think he was underwater sometimes, having to hold his breath. Make plans now, before the storms start tearing loose Friday night into Saturday. And if you go under the warning polygon, use that shot of adrenaline to get yourself up and to gather your loved ones (even if that just means your pets) and get to the safest place you have available. Nine times out of ten, even in a really bad tornado, if you do the right things, you're going to make it, and probably without serious injury.
And if you don't believe me on that, check out this old article from a taciturn meteorologist and storm chaser who is no longer with us, he died earlier this year, and have yourself a good belly-laugh at how even scientists get in serious fights sometimes. Chuck was right about this though. These really bad tornado days are nerve-wracking, and for people who have had close calls or lost someone in a tornado in the past, they can trigger downright shellshock-level fear in people. But objectively, even if you don't have a storm shelter or "safe room", which most people don't, you probably have a place that is good enough. And you have to use what you have. It really could save your life if a tornado hits your home or comes close to you.
And if you'd rather not read the grumpy-old-man version of him explaining why trying to drive out of the path of a tornado (instead of sheltering at home) was the wrong idea, then here is a good resource from NWS Kansas City about keeping your wits about you even though severe weather can get scary. I guess it's sort of like the reality of flying in a plane versus how dangerous people feel like it is. Everybody takes a greater risk by driving or riding in a car every day. (Especially if you live in places like Jasper or Huntsville, where on Highway 118/Old Hwy 78 or University Drive, people drive so crazy, you'd almost think it was Atlanta sometimes.) The odds of being seriously injured or killed in a tornado are relatively low even on a red-letter day like we have coming up. Especially if you take reasonable shelter, then the chances of being seriously hurt are so low, it's not worth the worry. It is only worth doing the right things to protect yourself and your family/friends when that time comes. And you know, I hope that moment doesn't come for people reading this. It's been a while since we've had a high-impact tornado risk like this, and I guess I'd forgotten how much the human side comes into play, not just dry scientific facts, where you hope a lot of people don't get hurt or lose their homes and whatever. But you can't afford to fool around with this. Have a plan for the worst, if you do get hit by a tornado, and hope for the best.
And hopefully we'll get through this event all right. It does look like a bad one, though - both Friday night and Saturday afternoon are looking threatening. It's not one anyone around here can afford to thumb their nose at. Have to play it very safe with this one.
SPC AC 130729
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 AM CDT Thu Mar 13 2025
Valid 151200Z - 161200Z
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
SOUTHEAST LOUISIANA INTO SOUTHERN AND CENTRAL MS/AL...
...SUMMARY...
A severe weather outbreak is expected on Saturday from the central
Gulf coast states/Deep South into the Ohio Valley. Significant
tornadoes (focused across the South), swaths of damaging gusts, and
hail are expected.
...Synopsis...
An upper cyclone over the Upper Midwest will lift northeast into
Ontario through Saturday evening. Meanwhile, a large-scale upper
trough over the Plains will eject east toward the MS Valley. Strong
southwesterly mid/upper flow (with a 500 mb jet streak near 100 kt)
will overspread the Lower MS Valley/Mid-South vicinity by 00z, and
continue east/northeast overnight into the Ohio Valley and central
Appalachians. An intense south/southwesterly low level jet greater
than 60 kt is forecast to overspread the central Gulf coast/Deep
South into the TN/OH Valley during the late afternoon and nighttime
hours. Rich Gulf moisture with dewpoints in the mid/upper 60s is
expected to be focused over LA/MS/AL and the FL Panhandle, and
possibly as far north as Middle TN and far western GA. 50s to low
60s F dewpoints will extend north into the Ohio Valley. This should
support a widespread risk for severe storms across much of the
central into the southeastern U.S. Saturday into early Sunday.
...Deep South/TN Valley vicinity...
Forecast guidance has generally trended toward less widespread
precipitation coverage Saturday morning as stronger height falls are
not expected until late morning/early afternoon as the Plains trough
ejects and a surface low begins to develop over the Mid-South.
Persistent strong southerly low-level flow will allow for a
moisture-rich boundary layer that should remain relatively pristine
across southeast LA into southern/central MS/AL before convection
develops by midday. Forecast soundings show cooling aloft will
support steep midlevel lapse rates atop this moist boundary layer,
leading to MLCAPE values perhaps approaching 2000 J/kg (decreasing
with northward extent in Middle TN). Vertically veering wind
profiles with strong anvil-level divergence amid moderate
instability should support robust updrafts and intense supercells.
Significant tornadoes, damaging gusts and large hail will be
possible through the afternoon and spreading into AL during the
evening/nighttime hours.
Additional convection is expected to develop along an
eastward-advancing cold front during the afternoon and into the
overnight. An organized line of storms will pose a risk for damaging
wind swaths and tornadoes across northern MS/AL into TN, eastward
into GA and the western Carolinas overnight.
...Ohio Valley...
Very strong deep-layer flow will be in place across the Ohio Valley
on Saturday with some convection possibly ongoing from southeast
Lower MI into western/central KY. The extent of severe potential is
uncertain and dependent on how much precipitation occurs early in
the forecast period. Too much convection early in the day could
largely limit destabilization and temper the overall risk. However,
if less convective contamination occurs, greater destabilization
could occur ahead of a deepening surface low lifting northeast from
the Mid-South to OH during the evening. Given the strength of
deep-layer flow at least some risk of strong/damaging gusts within
bands of thunderstorms should occur through Saturday night.
..Leitman.. 03/13/2025
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