SPC Jan 7, 2024 1730 UTC Day 2 Convective Outlook

[NorthGeorgiaWX]

SPC 1730Z Day 2 Outlook

Day 2 Convective Outlook  
NWS Storm Prediction Center Norman OK
1136 AM CST Sun Jan 07 2024

Valid 081200Z - 091200Z

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

...SUMMARY...
Severe thunderstorms capable of strong wind gusts and tornadoes are
expected from southeast Texas across the central Gulf Coast and from
Monday 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...
Shortwave trough currently extending from Great Basin through the
northern Baja Peninsula is forecast to move eastward today while
intensifying. By 12Z Monday morning this shortwave will likely have
matured into a mid-latitude cyclone centered over northeast NM, with
an extensive belt of strong mid-level flow throughout its southern
periphery. This cyclone is then expected to evolve eastward across
the TX Panhandle and OK throughout the day, with mid-level flow
strengthening considerably throughout its eastern periphery. By
Monday evening, 100+ kt at 500-mb will likely stretch from the
Edwards Plateau into the Ozark Plateau. Further strengthening of
this mid-level flow is anticipated overnight Monday as the cyclone
tracks a bit more northeastward, ending the period over western MO.
Intense low-level flow will accompany this cyclone as well, with a
large area of 50+ kt over the southern Plains early Monday. This
low-level jet will shift eastward throughout the day and overnight,
while gradually strengthening. By early Tuesday morning, 60+ kt
850-mb flow will cover much of the Southeast, with 70+ kt possible
from northern MS into middle TN and northern AL. 

Previous frontal intrusion (evidenced by the cold and dry conditions
over the southern Plains and Southeast Sunday) will limit the
northern extent of the moisture return and associated
severe-thunderstorm potential. General expectation is for secondary
surface cyclogenesis over central TX Monday morning, with the
primary low well to the north over the TX/OK Panhandles. This
secondary low (and associated warm front) should delineate the
northern extent of the severe potential as it gradually moves
eastward across central portions of east TX and into central LA
Monday afternoon and evening. This low is forecast to continue
eastward overnight Monday into early Tuesday, progressing across
central MS and AL. Severe thunderstorms are expected within the warm
sector ahead of this low, as well as along the associated cold front
as it surges eastward.

...North TX Early Monday...
As the strong mid-level flow associated with the cyclone moves into
southern Plains, a fast-moving line of showers and embedded
thunderstorms is expected to move across north TX early Monday
morning. Forecast soundings show very weak thermodynamics, limiting
overall updraft strength and duration. However, given the strong low
and upper level support, a narrow-line of forced convection may
become capable of locally gusty/damaging wind gusts as it moves
eastward.

...TX Coastal Plain/Southeast TX into southwest LA Monday Afternoon
and Evening...
Two rounds of strong to severe thunderstorms are possible across the
region Monday, with the first round likely beginning early Monday
afternoon as the warm sector moves into the region. Current guidance
suggests this warm sector will be characterized by temperatures in
the low 70s, dewpoints in the upper 60s, and moderate buoyancy.
However, given the prevalence of cloud cover and early period
showers, there is uncertainty regarding if temperatures can reach
the low 70s. If they do, some surface-based supercells capable of
all severe hazards, including tornadoes are possible. If
temperatures stay in the 60s, low-level stability would likely
inhibit surface-based storm development, mitigating the severe
potential. Consensus within the guidance has trended towards warmer
temperatures and tornado probabilities were increased across the
region as a result. A further increase in probabilities may be
needed in later outlooks if confidence in surface-based storms
increases.

Additional thunderstorm development is anticipated along the front
as it moves through, but the strength of these storms will be
predicated on coverage and strength of any warm sector development.
Strong wind gusts would be the primary severe risk with this
convective line.  

...Central Gulf Coast Overnight Monday into Tuesday Morning...
As the surface low continues eastward, a convective line is expected
to mature along the cold front as it encounters a moderately moist
and buoyant airmass and increasingly strong low-level flow. As the
line matures, it will likely transition from a more parallel
stratiform structure to a more organized leading-line, trailing
stratiform configuration. Robust low-level kinematics, characterized
by 50-60 kt just above the surface and 500+ m2/s2 of 0-3 km SRH,
suggest both significant-severe gusts and strong QLCS tornadoes are
possible.

..Mosier.. 01/07/2024

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