SPC Jan 8, 2024 0600 UTC Day 1 Convective Outlook

[NorthGeorgiaWX]

SPC 1200Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1154 PM CST Sun Jan 07 2024

Valid 081200Z - 091200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE
CENTRAL GULF COAST TONIGHT INTO EARLY TUESDAY MORNING...

...SUMMARY...
Severe thunderstorms capable of strong wind gusts and tornadoes are
expected from southeast Texas across the central Gulf Coast this
afternoon into early Tuesday morning. Greatest severe potential is
anticipated overnight from southeast Louisiana across southern
Mississippi and southern Alabama, and into the western Florida
Panhandle.

...Synopsis...
A potent, positive-tilt mid-level shortwave centered over the Four
Corners will undergo significant amplification as it emerges over
the Southern Plains through the forecast period. South of the
primary vort max, a 90-100 kt H5 jet streak will round the base of
the trough and move quickly eastward, intensifying further, as it
overspreads the mid-MS valley into early Tuesday. Coincident with
the robust forcing aloft, a lee cyclone over northeast NM will
quickly deepen below 1000 mb as it tracks eastward over the TX
Panhandle and OK. South of the low, strong low-level mass response 
will rapidly advect a modifying Gulf air mass northward into
portions of central/southeast TX and eventually across the central
Gulf Coast. Strong low-level warm advection ahead of the
intensifying upper-level and surface cyclone will support numerous
showers and thunderstorms across the southern Plains and lower MS
Valley today into early morning Tuesday. Strong kinematics and
sufficient buoyancy within the onshore warm sector will support
organized storms capable of all hazards, including a couple strong
tornadoes.

...North TX into the ArkLaTex...
Showers and embedded thunderstorms should be ongoing early this
morning within a strong low-level warm advection regime ahead of the
surface low and cold front in western north TX/OK. Area model
soundings show weak and elevated buoyancy profiles atop a mostly
stable surface layer ahead of the deeper returning surface moisture.
Despite the marginal buoyancy, a narrow line of forced convection
may evolve along the cold front and become capable of locally
gusty/damaging wind gusts as it moves eastward from north TX into
far southern AR and northern LA.

...Southeast TX to southwest LA...
As the surface low continues to deepen over OK and western North TX,
strong low-level mass response will rapidly draw a modifying Gulf
air mass northward into south-central and southeast TX. Surface
dewpoints will gradually rise into the low to mid 60s F as the air
mass moves farther inland. Widespread cloud cover and warm advection
showers will limit solar heating, but inhibition should weaken
through the early afternoon as deep-layer ascent increases and
gradual warming of the boundary layer supports 1200-2000 J/kg of
MLCAPE. Scattered thunderstorms should gradually evolve from the
initial low-topped showers within increasingly strong low-level and
deep-layer shear profiles sufficient for supercells. A secondary
surface low along the advancing warm front may also locally back
surface winds, favoring strong low-level mesocyclones with the
potential for damaging gusts and a few tornadoes.

Additional storms are likely to develop later in the afternoon as
the surface cold front approaches from the west. Behind the
secondary surface low, veered low-level flow suggests a more linear
orientation may evolve with upscale growth of the new convection
into a broken line/QLCS with greater potential for damaging wind
gusts. Still, 0-1 km shear in excess of 30 kt may support some risk
for line embedded circulations with enhanced damaging gust or
tornado potential into the evening and overnight hours.

...Central Gulf Coast tonight into early Tuesday...
An initial round of elevated showers and thunderstorms is expected
to develop by early to mid afternoon over parts of the central Gulf
coast ahead of the warm front moving onshore. As the Gulf air mass
gradually moves inland, increasing surface dewpoints will allow for
moderate buoyancy to develop coincident with a strong increase in
mid and low-level shear profiles ahead of the advancing upper
trough. A 60-70 kt low-level jet will continue to support strong
warm advection and the development of additional thunderstorms ahead
of the main convective line to the west into the evening and
overnight hours. A few supercells may evolve ahead of the line over
parts of southern MS, southwest AL and the western FL Panhandle
within a very strongly sheared environment. STP values of 3-5 on
area model soundings suggest the potential for a couple of strong
tornadoes. Damaging wind gusts and line-embedded tornadoes also
appear likely as the QLCS advances quickly from west to east.

..Lyons/Grams.. 01/08/2024

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