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4/7-4/10 possible severe WX

I was about to say I see this thing looking like a derecho ... those are unpredictable until they fully form ... usually come in faster as well
Any MCS type system is hard to model. Often direction and strength don't get modeled as well as them simply existing. They can last longer than modeled or shorter depending on each stage they go through. Only way to know how far/where it goes is to see on that day.
 
I've learned a lot over the years on this Board, but one thing I haven't is, where on a Hodo does it tell you where it is for. That may be a stupid question but I have looked as closely as I can and can't. All I see is Long and Lat numbers but that doesn't help me. If it is not on there, when you post could you just briefly put where it is for. Thanks in advance.
 
Is there supposed to be bad storms in alabama today? I know there might be Saturday
 
Why I'm saying is there supposed to be bad storms is cause simulated radar doesn't show anything this afternoon and tonight. But parameters are decent. I'm guessing theres a missing piece somewhere
 
Why I'm saying is there supposed to be bad storms is cause simulated radar doesn't show anything this afternoon and tonight. But parameters are decent. I'm guessing theres a missing piece somewhere
.SHORT TERM...
/Updated at 0916 AM CDT Thu Apr 08 2021/

Short-term forecast remains in good shape. We will continue to
watch for any convective development across our northeastern
counties through noon. This area has the best potential for an
isolated strong to severe storm. Otherwise, mostly dry conditions
are expected for the rest of the day. Will take a look at
potentially increasing high temperatures a bit due to decreased
cloud cover later today.
 
And 1 new SPC outlook later, DFW has gone from being in the enhanced risk area to barely being in the slight risk area, lol...
 
HSV AFD was a good discussion



An active period awaits us in the short term. The cold front from
earlier today will stall over central Alabama. Its parent low and
associated upper level cutoff low will continue to track northeast as
they rotate around a second shortwave trough over the High Plains. A
split flow jet structure aloft creates a complex synoptic pattern
with an even more complex severe weather setup.

On Friday, the subtropical jet will push a shortwave trough from
California into the Southern Plains in more zonal flow aloft. As this
trough tracks toward the Southeast, a surface low will generate over
Texas. With the tightening low level pressure gradient, southerly
surface winds will gust near 20 mph tomorrow afternoon. Additionally,
the northern stream jet will push the High Plains shortwave trough
into the Central Plains and intensify it into another cutoff low. The
trickiest part of this forecast is how this new cutoff low interacts
with the shortwave trough, and unfortunately, there is not very high
confidence in a solution at this time.

What we are able to identify at this time is that the environment
will be primed for severe weather over the TN Valley. In spite of
lacking deep southerly flow, moisture availability will be more than
sufficient for deep, moist convection. Additionally, an elevated
mixed layer (EML) will accompany the Texas-originated surface low as
it tracks into the Southeast, providing steep mid-level lapse rates,
large values of CAPE, and introducing a threat for large hail.
Lastly, an intensifying southwesterly low level jet on the magnitude
of 50-60 kts will precede the surface low and its attendant cold
front. This will elongate hodographs and allow the large CAPE from
the EML to be surface-based.

An initial and smaller MCS will track through the Deep South based
on the track of the shortwave trough on Friday evening. This is
currently our greatest source of uncertainty, because global
guidance, ensemble guidance, and CAMs show this line tracking
anywhere from along the Gulf Coast to directly over the TN Valley.
Threats with this first round will be large hail, damaging winds, and
tornadoes.

There is higher confidence in a second, much larger QLCS tracking
through the Southeast late Friday night into Saturday morning.
Regardless of the track of the initial MCS, this second line will be
severe with damaging winds, potentially over 70 mph, large hail, and
again tornadoes will be possible. This line of storms looks to enter
Northwest AL as early as midnight Saturday, but most likely around 4
AM, and then not exit northeast AL until Saturday around mid-morning,
but potentially as late as noon. Showers will be possible through
Saturday evening, as the cold front itself does not push through
until Saturday night. With multiple rounds of heavy rainfall, most
areas will see at least 2" of rainfall, with some areas seeing higher
amounts. Due to mostly saturated soils, flash flooding will be
possible.

Now for the important part: what could go wrong? It is worth noting
that any guidance that pushes that initial MCS south of our area has
a weaker, yet still severe, second QLCS that tracks through the TN
Valley. Additionally, it is possible that should the initial MCS
track through the TN Valley, it creates a rain-cooled environment
that is not surface-based and reduces the severity of the second
round QLCS. Regardless, it is important to treat this as though both
rounds will be severe. Careful mesoscale analysis of corfidi vectors,
steering flow, and any theta e ridges will be essential as we try to
predict with a few hours` notice where the MCS may track. As we have
seen multiple instances of in the summer, MCS tracks are often not
well represented in CAMs and will need to be relied upon more with
careful observational analysis.
 
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