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Severe 3/17/21 Severe Weather Outbreak Al/Ms/Tn/Ar nowcast

Something to take into account: Montgomery and points south and east are untouched. Obviously parameters are not as intense down there, but pretty much no contamination until whatever comes through
 
Is the wedge of cold air over north GA gonna move out? Seems like over time its actually moved further south
 
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Mesoscale Discussion 0212
NWS Storm Prediction Center Norman OK
0549 PM CDT Wed Mar 17 2021

Areas affected...Much of southeastern Mississippi and central
Alabama

Concerning...Tornado Watch 29...33...

Valid 172249Z - 180015Z

The severe weather threat for Tornado Watch 29, 33 continues.

SUMMARY...The risk for tornadoes, a couple of which could become
strong and particularly damaging, is expected to continue to
increase through mid to late evening as an organizing squall line
overspreads the region. This may also be accompanied by more
general strong to severe surface gusts. A new tornado watch will be
needed by 7 PM CDT.

DISCUSSION...Large-scale ascent, aided by lower/mid tropospheric
warm advection beneath difluent high-level flow, continues to
support discrete thunderstorm development within a relatively broad
warm sector. Areas of the warm sector not substantially impacted by
prior convection remain characterized by CAPE of 1000-2000 J/kg, and
wind profiles across the region exhibit strong deep-layer shear and
sizable, clockwise-curved low-level hodographs. This environment
remains potentially conducive to long-lived supercells with strong
low-level mesocyclones posing a risk for tornadoes.

While the onset of diurnal cooling could result in at least some
decrease in instability by 00-01Z, favorable large-scale forcing for
ascent seems likely to maintain discrete storm development across
central Alabama, as a linear convective system continues to evolve
upstream, across southeastern Louisiana through southern and eastern
Mississippi. This is occurring ahead of a vigorous short wave
trough turning east-northeast of the southern Great Plains. As this
feature progresses into the lower/middle Mississippi Valley through
mid/late evening, south-southwesterly 850 mb flow is forecast to
strengthen in excess of 50 kt in a corridor along/ahead of the
evolving squall line.

Further enlargement of low-level hodographs will maintain the risk
for tornadoes with both the discrete supercells preceding the the
squall line and those forming within the squall line. This will
include the potential for strong tornadoes. Otherwise, corridors of
potentially damaging wind gusts will probably begin to increase as
the evolving squall line continues to organize and accelerate
northeastward.

..Kerr.. 03/17/2021
 
Models were a all out bust here today. Warm front was progged to be 50 miles north of me by now. Models were showing cape up to 2000 j/kg and nowhere close. Models were showing high of 76 only missed it by 16 degrees. Lol
 
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Mesoscale Discussion 0213
NWS Storm Prediction Center Norman OK
0609 PM CDT Wed Mar 17 2021

Areas affected...Far eastern Arkansas...Northern Mississippi and
Alabama...into southern Tennessee.

Concerning...Tornado Watch 32...

Valid 172309Z - 180015Z

The severe weather threat for Tornado Watch 32 continues.

SUMMARY...A replacement tornado watch for the northwestern half of
Tornado watch #32 will be coordinated shortly.

DISCUSSION...Numerous thunderstorms including semi discrete
supercells are ongoing across the area. Strong low-level shear
(450-500 0-1km SRH) sampled from the MEG VWP suggests the tornado
threat is likely to continue after the 00z expiration time of WW32.
Expansive convective coverage into north-central Alabama may
somewhat impact buoyancy near the diffuse warm front across southern
Tennessee. However, additional thunderstorm development across far
eastern Arkansas may support the severe threat well into the night
across north-central Alabama. A new tornado watch will be
coordinated shortly.

..Lyons/Guyer.. 03/17/2021
 
Confirmed reports of a brick home having its wall blown out near Clanton
 
Currently 23:22z, the 18z HRRR had the line about where it is now around 01z-02z.
 
Once more reports come in the next few days it might + some later, not lots of strong, long trackers tho, but more so cyclic supercells 95B092FD-01D5-4CF3-9A3B-DFAAA497FCE3.png
 
Getting some development in that previously untouched area south/east of Montgomery
 
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