Day 1 Severe Weather Outlook

Valid 022000Z – 031200Z


Strong to severe thunderstorms may impact parts of the Mississippi
Delta and central Gulf Coast States, offering damaging wind gusts
and a tornado threat.

…20Z Update…
A more coherent band of thunderstorms has recently developed across
central/south-central LA amidst the modest convergence with the
broad frontal zone. Recent surface analysis shows dewpoints in the
upper 60s/low 70s within the downstream air mass across much of
southeast LA and southern MS. However, given the strong
front-parallel flow aloft, resulting north-northeastward storm
motion may result in storms lagging behind their own outflow. This
would keep storms predominately elevated despite the increasing
downstream instability. A more easterly storm motion would likely
support a higher severe risk.

Even so, potential still exists for occasional/sporadic storm
organization and the risk for damaging wind gusts with any bowing
line segments. Additionally, given the strong 1-2 kft winds sampled
by recent area VADs, a low tornado potential also continues,
particularly with any deep convection that can persist ahead of the
primary line.

..Mosier.. 01/02/2020

.PREV DISCUSSION… /ISSUED 1022 AM CST Thu Jan 02 2020/

A strong upper trough is tracking across TX and northern Mexico this
morning, with 75-100 knot southwesterly midlevel winds extending
from the western Gulf of Mexico into parts of LA/MS/AL. At the
surface, a frontal boundary extends from southwest LA into central
MS. South of the boundary, dewpoints in the mid-upper 60s are
streaming northward and resulting a marginally unstable air mass
(MLCAPE around 500 J/kg). All 12z model guidance agrees that
scattered thunderstorms will form along the front this afternoon
over LA/MS and track eastward as the air mass destabilizes northward
across AL. The best environment for surface-based storms, including
possible supercells and bowing structures, will be in the SLGT risk
area of central LA into central MS and west-central AL. Forecast
soundings in this area show substantial low-level shear conducive to
a few tornadoes, but convection will likely be linear in nature,
suggesting QLCS wind damage and tornadoes are the main threats. The
storms should generally weaken as they track across central/northern
AL, but may remain occasionally strong/severe through much of the


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