This is one of those things it's tough not to post about if you see it when scrolling and are inclined toward watching the weather. While the ridge of high pressure is likely to keep most of the severe thunderstorms deflected to our Northwest, it is sort of a close call. And the weather looks awful for places like Memphis, back into much of Arkansas, at least Western Kentucky, at least the Western third of Tennessee as well, and at least Southern parts of Illinois and Indiana. Some of the severe weather threat may stretch beyond this, even down into Alabama, mainly Northwest Alabama. But in the hottest zones for this severe weather, they have a similar threat to what we did on March 15, where supercell thunderstorms capable of long-track, damaging tornadoes are likely within mainly that broad "High" (Level 5 out of 5) and "Moderate" (Level 4 out of 5) risk zone.
Notice that the hatched area for the significant tornado threat is anywhere from a 10%, 15%, or 30% chance of a tornado - could be a particularly damaging one - within 25 miles of any given point. So this could be a full-blown tornado outbreak mainly affecting people in and near those 15-30% zones that correlate to the Level 4-5 Risk of severe weather in general today.
A large area over several states is also outlooked for a 30% risk of damaging winds. The hatching means they could reach hurricane force, 75 mph or greater.
And then there is a different section hatched for the threat of very large hail, up to at least golfball sized. It covers some of the same hot zones for tornadoes and damaging winds but also stretches back into parts of Texas, Oklahoma, and even Northern Louisiana.
Locally our chances for severe weather are low tonight. They increase some in far Northwest Alabama, up around the Shoals into Southern Middle Tennessee, as opposed to most of North Alabama, which has a very low risk of any severe thunderstorms sustaining, the "leftovers" of this event. For a few places like Waynesboro, Lawrenceburg, up through Columbia, Franklin, Nashville, all the way up into Kentucky, where there's a Level 3 "Enhanced" Convective Risk, the threat for severe weather is roughly what it was the other night when a few tornadoes impacted Middle Tennessee. That was Sunday night/Monday morning. The risk level is similar tonight.
But the main threat is for about the Western third of Tennessee and back into Arkansas, up into Kentucky and at least Southern parts of Illinois, Indiana, and Ohio - Southwest Ohio. That's where the main zone for supercell storms looks to my weary eye.
Nashville and points North and West are also at risk for some flooding issues, as is a good bit of Kentucky.
Even down here, people should go to bed with a NOAA Weather Radio on alert (and remember, the Cullman transmitter is out, you need to tune to the Arab or Oneonta channels if you live in Cullman County) with battery backup and another source of getting alerts like Wireless Emergency Alerts enabled on a cell phone, or at least a reliable radio station that cuts in during local severe weather. Something to wake you up. People can easily sleep through outdoor sirens, which vary in how reliable they are to go off during a tornado warning anyway, from place to place, and even from one event to the next sometimes. I've heard them sounded when there was clearly no tornado threat in the area (outdoor sirens), and there have been times I've lived in places where they didn't always go off when they were supposed to. Anyway, they are tough to hear indoors and wake up, the way a weather radio alarm sound will wake you up. Or the way that really abrasive emergency alert sound over the radio will wake you up. Or even how a cell phone alert sounds. A lot of people get aggravated waking up at night for Amber Alerts. (Though they wouldn't find it annoying if it was a kid they knew who'd gone missing. They'd be glad the system was there to get the word out. And we humans chide cats for being too selfish . . . tsk tsk.) So if you make sure the cell phone is not in a "sleep" or "do not disturb" mode and has WEA enabled, you should be all right. Ideally you want to have a couple ways of getting warnings in case one fails.
One time I knew a meteorologist who found it easy to go back to sleep and who kept strange hours anyway, would stay up all night writing papers sometimes. And he hadn't plugged up his weather radio in years. When he knew there was a chance for severe weather, he would just set an alarm every 2-3 hours during the night and check on the weather. If nothing was close to him, he'd set an alarm again for the next time he thought he should check on it. So . . . different strokes for different folks.
This front is going to stall out and bring more chances for severe thunderstorms tomorrow and Friday, mainly to the Ohio Valley. And they will have a risk for flooding too.
Down this way, we mainly have to watch Saturday and Sunday, probably the focus coming Saturday night into very early Sunday morning. That's the only time it looks like our severe weather threat in North Alabama/Southern Middle Tennessee is likely to get really organized.
As for tonight, I'd respect the threat just because this is such a powerful system that may impact areas sort of near here in a strong way. And sometimes even the leftovers of a system like that can pack a punch. But our threat is low tonight. And I think we're all right tomorrow and Friday. But then as the front moves through here, I'd really watch Saturday into Sunday, probably another overnight threat, mainly Saturday night.
If you know anybody in the highest risk zones of this event especially, like Western Tennessee into Arkansas, Kentucky, ideally I'd hope they could get to a storm shelter or the underground part of a basement ahead of any of these tornadoes that might form.
But since most people don't have access to those, the best advice is to make sure you're out of a mobile home if you get a Tornado Warning. Get to a sturdier house, other strong building, or (if you're lucky) a public shelter in enough time.
And in that sturdy house, get to the lowest floor. Get into a small room like a bathroom or closet. Or if all you've got is a hallway, that's fine too. They tend to hold up well. Walls are less likely to collapse in those smaller spaces, especially the walls of a bathroom that have all those pipes running through them. Try to make that room near the center of the building; put some walls between you and the outside. And of course that means you're staying away from any windows or any doors that lead to the outside.
With an outbreak like this, it's more important than usual to take a few extra precautions. Like even if you're fortunate enough to have a basement, I'd try to get up under something sturdy, like maybe the stairs, a table, a desk, or a workbench. Because sometimes in a really damaging tornado, debris can fall from upstairs. And wherever you shelter, it's a good idea to use what you have to protect your body from debris that could fall or fly around in the winds. If all you have is some blankets or a pillow or cushion, that could protect you from simple things that could fly around in the winds at high speeds, like broken glass. Especially need to protect your head. Maybe if you've got a small mattress like a futon mattress, that could help too. The ideal for protecting your head is a safety helmet like you'd wear for riding a bike or motorcycle, or playing sports . . . a football helmet is great. Most deaths from tornadoes come from head injuries. So even in a worst-case scenario, where the whole house fails and somebody gets picked up by the winds, a helmet can save a life. Even Theodore Fujita noticed that, the guy who (with Allen Pearson) came up with the original F-scale for rating tornadoes. Way back in the 1970's-80's, he started recommending people wear a helmet if they had one around the house. Because he noticed that in some of the worse tornadoes.
And we've seen lots of examples proving that point over and over again.
This is a dangerous day for a lot of people, dangerous in the way the middle of March was for us in Alabama. Even if the way it played out, it was mainly the Southern half of the state that got hit hardest. But this is a similar risk out there for West TN, Arkansas, into mainly Kentucky, a relatively rare day that you might see once or twice a year, or maybe once every two or three years, for any one section of the country that falls under it.
Now locally, we're probably not going to have that many issues. We might not even have any issues. Our risk of severe is low, but it'd still be a good idea to be able to get warnings tonight just in case. I'd say the chance as you get up into Middle Tennessee is medium, and then Western TN and those other places nearby, the risk of severe is high, including a significant tornado risk.
We do have a Wind Advisory in effect, and winds could gust up to 35 mph today.
We'll see a High near 85. And from now through Saturday, our Highs should stay in the mid-80's with Lows in the mid/upper 60's, pretty warm for this time of year. Some places like Birmingham may set new records for High temperatures.
Saturday night into Sunday, rain and thunderstorms are likely, and some storms could become severe around here. The High should be in the lower 70's, Low in the lower 60's on Sunday. And it'll be a breezy day even behind the storms, probably rain showers lingering much of the day.
And then we have a major cooldown, unseasonably cool, behind this front. Skies will clear out Monday and especially Tuesday with Highs struggling to even make it to 60 degrees, the Low actually dipping down into the 30's by Tuesday morning, 40's Monday morning.
So this is a pretty gnarly weather pattern all around.
ZCZC SPCPWOSPC ALL
WOUS40 KWNS 021305
ARZ000-ILZ000-INZ000-KYZ000-MOZ000-MSZ000-TNZ000-021800-
PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0805 AM CDT WED APR 02 2025
...Outbreak of tornadoes and severe thunderstorms expected over
parts of the Mid-South and the lower Mississippi and Ohio River
Valleys later today and tonight...
* LOCATIONS...
Eastern Arkansas
Western Tennessee
Southeast Missouri
Western Kentucky
Southern Illinois
Northwest Mississippi
Southern Indiana
* HAZARDS...
Numerous tornadoes, several intense and long track
Scattered damaging winds, some hurricane force
Scattered large hail, some baseball size
* SUMMARY...
A tornado outbreak is expected today and tonight from parts of
the lower Mississippi Valley into the Mid-South and lower Ohio
Valley. Numerous tornadoes, along with multiple EF3+ tornadoes,
appear likely. In addition, tornadoes, significant severe wind
gusts, and large hail to very large hail will be possible across
a broad area from north Texas northeastward to the southern
Great Lakes.
Preparedness actions...
Review your severe weather safety procedures for the possibility
of dangerous weather today. Stay tuned to NOAA Weather Radio,
weather.gov, or other media for watches and warnings. A tornado
watch means that conditions are favorable for tornadoes to form
during the next several hours. If a tornado warning is issued for
your area, move to a place of safety, ideally in a basement or
interior room on the lowest floor of a sturdy building.
&&
..Thompson.. 04/02/2025
$$
SPC AC 021248
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0748 AM CDT Wed Apr 02 2025
Valid 021300Z - 031200Z
...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE
MID-SOUTH AND LOWER MISSISSIPPI VALLEY...
...SUMMARY...
A tornado outbreak is expected today and tonight from parts of the
lower Mississippi Valley into the Mid-South and lower Ohio Valley.
Numerous tornadoes, along with multiple EF3+ tornadoes, appear
likely. In addition, tornadoes, significant severe wind gusts, and
large hail to very large hail will be possible across a broad area
from north Texas northeastward to the southern Great Lakes.
...Synopsis...
A strong mid/upper-level trough with associated 100-120 kt mid-level
jet streak will advance quickly northeastward today across the Upper
Midwest and Great Lakes. A broader area of 50-70+ kt southwesterly
mid-level flow will persist over much of the southern Plains into
the lower/mid MS Valley and OH Valley. At the surface, the primary
low over far eastern NE/western IA this morning is forecast to
develop northeastward in tandem with the upper trough today,
eventually reaching the Upper Midwest by this evening. A trailing
cold front will continue east-southeastward across the southern
Plains and Ozarks today, before eventually stalling and lifting
northward as a warm front tonight. Weak secondary surface low
development is possible this afternoon and evening along or just
ahead of the front across AR into the Mid-South.
...Ozarks into the Lower/Mid Mississippi Valley, Mid-South, Ohio
Valley, and Southern Great Lakes...
Robust convection is ongoing this morning from northern MO
southwestward to southern OK and north TX along/near the cold front.
Even with some capping concerns noted on area soundings ahead of
this activity, a very strong (60-70 kt) southerly low-level jet is
providing ample low-level moisture transport to support continued
convective intensity. Steep mid-level lapse rates and strong
deep-layer shear are also fostering some embedded supercell
structures, with associated large hail threat. Otherwise, given the
strength of the low-level flow and very strong effective SRH,
scattered severe/damaging winds and a few tornadoes will remain the
primary threats with this line of convection as it continues
eastward this morning across the remainder of OK into AR and MO. A
strong tornado may occur with any sustained surface-based supercell.
The effect that this morning convection has on downstream afternoon
severe potential across the lower/mid MS Valley may be substantial.
Most guidance shows either a gradual weakening trend with the line
by late morning/early afternoon, or a devolution into a broken line
of supercells. Mid/high-level cloud debris could inhibit daytime
heating to some extent across much of the warm sector, and the
northern extent of the weakening line over northern MO may serve as
a cutoff for surface-based thunderstorms across the Midwest and OH
Valley later today. Even with these continued uncertainties, it
appears likely that a corridor of moderate to strong instability
will develop this afternoon across the lower MS Valley into the
Mid-South and lower OH Valley, generally ahead of whatever remains
of the ongoing/morning convection. With more nebulous/weaker
large-scale ascent over these regions given their spatial
displacement from the ejecting upper trough, there may be a more
mixed/supercell mode this afternoon/evening, particularly with
southward extent.
Current expectations are for several intense supercells and clusters
to develop by 20-00Z from far northern LA into eastern AR, northwest
MS, western TN/KY, and southeast MO, and southern IL/IN. This region
appears to have the most favorable overlap of moderate to strong
instability, strong deep-layer shear, and ample low-level shear to
support multiple tornadic storms. With most guidance showing
enlarged, curved hodographs through the boundary layer, and
effective SRH forecast to generally range 250-400+ m2/s2, several
strong tornadoes are likely. Multiple EF-3+ tornadoes should also
occur given the very favorable parameter space forecast, but this
high-end tornado potential may be dependent on a relative lack of
supercell/cluster interactions, which are difficult to pinpoint.
Still, based on latest high-resolution guidance trends showing
multiple intense supercells developing, the High Risk has been
expanded a bit southward with this update to include more of eastern
and south-central AR. The tornado and severe/damaging wind threat
will likely continue after dark, with updraft interactions
suggesting a messy mode, with clusters/lines and embedded supercells
all possible.
In addition to the tornado threat, large to very large hail (up to
2-3 inches in diameter) and severe/damaging wind gusts may occur
with these supercells and bowing clusters. A linear mode appears
more likely with northward extent across the mid MS Valley into the
southern Great Lakes as the cold front continues eastward today.
But, this area will also have less time to destabilize ahead of the
ongoing convection, which casts some uncertainty on the northern
extent of the substantial severe threat. Have trimmed the
Marginal/Slight Risks some across the Upper Midwest, but the
Enhanced Risk remains unchanged for now. Some risk for supercells
ahead of the line/clusters will exist across the OH Valley/Midwest.
But, confidence in this scenario occurring was not great enough to
expand the Moderate Risk for tornadoes northward into more of IN and
western OH.
...Southern Plains...
With the cold front expected to stall and eventually begin lifting
northward tonight, additional supercells may develop late in tandem
with ascent preceding another shortwave trough and a strengthening
southerly low-level jet. With steep mid-level lapse rates present
and ample MUCAPE and deep-layer shear, this convection should pose a
threat for mainly large to very large hail.
..Gleason/Leitman.. 04/02/2025
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