SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1134 AM CST Thu Jan 11 2024
Valid 121200Z - 131200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR NORTHERN
AND CENTRAL MISSISSIPPI AND FAR NORTHWEST ALABAMA...
...SUMMARY...
Severe thunderstorms capable of producing strong gusts, some
potentially to 75 mph, and a few tornadoes, are possible across
parts of the Southeast and into the Carolinas Friday through Friday
evening. Highest chance of severe wind gusts is over northern and
central Mississippi and far northwest Alabama Friday morning.
...Synopsis...
A strong shortwave trough is expected to extend from the central
Plains through central TX early Friday. An intense jet streak will
accompany this shortwave, characterized by 110-120 kt at 500 mb.
Expectation is for this shortwave to move quickly northeastward
throughout the period, traversing the Mid-South, Mid MS Valley and
Lower/Middle OH Valley while also becoming increasingly negatively
tilted. The strong mid-level flow will be maintained during this
time frame as well, spreading eastward/northeastward across much of
the Mid-South, TN Valley and into the Upper OH Valley.
Primary surface low associated with this shortwave will likely be
over central MO early Friday morning, before gradually moving
northeastward while occluding. Secondary triple-point low is
anticipated farther south, likely in the central AR vicinity early
before then tracking eastward across the southern TN and northern
AL/MS/GA vicinity. Severe risk will be confined south of this
secondary low, beginning early across the Mid-South before shifting
eastward across the Southeast and into the Carolinas throughout the
day. Given the strong kinematic fields and modest buoyancy, strong
gusts are expected to be the primary severe risk, but some
line-embedded tornadoes are possible as well.
...Mid-South vicinity Friday morning into the afternoon...
A convective line will likely be ongoing early Friday morning across
eastern AR. General expectation is that this line will become better
organized Friday morning as strong large-scale forcing for ascent
and the intense mid-level jet streak spread eastward/northeastward.
Thermodynamic profiles suggest this line may be quite shallow, with
limited lightning production. Even so, the strong ascent and intense
wind fields will likely result in a strongly forced, fast-moving
convective line capable of strong, potentially significant, gusts.
General northeastward progression of this line will result an
increasing northerly displacement of this line from the better
low-level moisture. This evolution will likely lead to an
increasingly elevated storm as well as increasing low-level
stability. These factors should result in lower probabilities for
strong gusts as the line moves into central/eastern KY and eastern
TN during the afternoon.
...Southeast Friday morning into the evening...
As the primary surface low occludes over the Mid MS valley, and
associated cold front is forecast to move quickly eastward across
the Southeast states. Low 60s dewpoints are expected to advect
northward just ahead of this front across southern portion of MS,
AL, GA, and the FL Panhandle, with the fast eastward-progression of
the cold front acting as a limiting factor for stronger moisture
return. This limited low-level moisture, combined with warmer
mid-level temperatures, will likely limit overall buoyancy,
tempering updraft strength and storm severity. Some stronger storms
are still possible, particularly if low-level moisture is better
than forecast, with strong kinematics supporting the potential for
some damaging convective gusts. Cell mergers could also augment
storm strength enough to produce some strong gusts. A tornado or two
is also possible if a storm can maintain discrete characteristics
and longer updraft duration. However, given the anticipated
thermodynamic profiles, the tornado threat appears lower than
previously anticipated.
...Carolinas late Friday afternoon through the evening...
Warm-air advection showers and thunderstorms will likely spread into
the region during the afternoon, ahead of the cold front approaching
from the west. Strong vertical shear will be in place, and a few of
these storms could produce small hail. A lower chance for stronger
gusts will exist with this activity as well, largely a result of its
elevated character. Potential exists for storms to trend towards a
more surface-based character as low-level moisture increases ahead
of the approaching front, particularly across southern portions of
the region. This could lead to a few stronger convective gusts and
maybe even a brief tornado. However, poor lapse rates limited
buoyancy and persistent low-level stability should limit updraft
strength and duration.
..Mosier.. 01/11/2024
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