re: Severe Weather - Today - LA, MS, AL, NW FL

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In addition the early day shortwave will lead to weaker winds in the 800 mb area and a veer-back-veer profile in the lowest levels with a hodograph depicting a pronounced kink due to these weaker winds. This type of shear profile may be both good and bad. It should lower the potential for strong sustained low level mesocyclones and thus the tornado threat would be more isolated and brief. On the other hand it may actually help convection initiate as there will be less turbulent mixing and shear to decapitate infant updrafts. Finally this shear profile would increase the potential for very large hail as it would result in greater mid and upper level cloud layer shear which is far more important for copious amounts of large hail growth than just being unstable.

Although we should mention that it most certainly will be very unstable with MLCAPE possibly near 3000 J/KG and a large amount of instability in the hail growth zone. Several sounding analogs suggest that any mature supercell in this area will have the potential to produce baseball to softball size hail. If supercells do form and remain isolated past 9 pm, we will have to closely monitor the 800 mb flow as the approach of the next trough could bring more cyclonic curvature in the low levels and lead to a higher tornado potential. Remember, severe storms are still not a certainty in this region as it is possible the subsidence wins out - but based on the various CAMs we estimate a 60-70% chance there will be severe weather somewhere in this area between 5 and 10 pm.

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thanks for bolding the important stuff dude unlike slackster out here giving us walls of text

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When is this evening supposed to be?

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..THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF
LOUISIANA...MISSISSIPPI...ALABAMA...AND THE FLORIDA PANHANDLE...

...SUMMARY...
Severe thunderstorms capable of tornadoes and extensive wind damage
are possible across parts of Louisiana, Mississippi and Alabama on
Thursday. Scattered severe storms are also possible as far east as
the Florida Panhandle, and as far north as western Tennessee.

...Synopsis...
An upper trough will amplify as it approaches the lower MS Valley
with mid to upper winds increasing to 60-80 kts. At the surface, a
cold front/outflow composite boundary will extend from eastern TX
into AR in the morning, and will shift east through the period.
Ahead of this early activity will be a deepening surface trough.
Preceding the front and early storms, southwesterly low-level winds
will create a surge of theta-e across LA, MS, and AL during the day,
with mean boundary layer dewpoints increasing to 68-70 F.

Very strong large-scale lift will develop over the lower MS Valley
during the day, with intense deep-layer differential divergence.
Cooling aloft will also accompany the cold front, further aiding
destabilization. The result will be widespread thunderstorms, with
corridors of damaging wind and tornadoes.

....LA...MS...AL...Western FL Panhandle...
Storms are expected to be ongoing Thursday morning along the cold
front/outflow, from southern AR into eastern TX. Some of these
storms could produce strong wind gusts or marginal hail.

Later in the day, a strong surge of deeper low-level moisture will
spread across LA and MS, coincident with 850 mb winds increasing to
over 50 kt. Both instability and shear will increase, and conditions
will become favorable for supercells and tornadoes. Forecast
soundings indicate effective SRH on the order of 300-400 m2/s2
across the entire area. Thus these midday storms may be severe with
a few tornadoes possible should they remain cellular.

Meanwhile, the activity along the cold front is expected to
intensify as it encounters this stronger instability into central
and eastern LA, and continuing across central and eastern MS during
the day. By late afternoon, an intense QLCS is forecast, likely
absorbing the earlier activity and producing corridors of
destructive winds and tornadoes. The most intense activity may also
spread into western Alabama, with a gradual decrease in overall
intensity overnight across eastern AL and into FL.

Early convection due to warm advection in the 15-18Z period lends
some uncertainty as to air mass quality for latter-day convection
with the front. If the rain is too widespread across LA and southern
MS, it could temper instability for the expected QLCS. On the other
hand, if the midday activity remains more cellular, several
tornadoes could occur. As such, will defer possible upgrade to
Moderate Risk to upcoming Day 1 updates.

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but does that mean that tomorrow is directly after today?

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