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ACUS01 KWNS 100101
SPC AC 100059

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0659 PM CST Sat Dec 09 2023

Valid 100100Z - 101200Z


Scattered severe storms capable of producing tornadoes, wind damage
and isolated large hail will continue this evening across parts of
the central Gulf Coast states and Tennessee Valley.

...Tennessee Valley/Central Gulf Coast States/...
The latest water vapor imagery and 500 mb analysis show a
progressive upper-level trough over the Ozarks, with a 50 to 06 knot
mid-level jet evident in southwesterly flow from the mid Mississippi
Valley into the southern Great Lakes. At the surface, a cold front
is moving southeastward through the Ohio and Tennessee Valleys.
Mosaic radar imagery shows a nearly continuous line of strong to
severe thunderstorms ahead of the front from central Kentucky
extending southwestward into north-central Mississippi and central
Louisiana. These storms are located along the western edge of a
weakly to moderately unstable airmass, and near the axis of a 35 to
45 knot low-level jet.

RAP forecast soundings this evening, along the axis of the strongest
low-level flow, from central Mississippi into far southern Tennessee
have 0-3 storm-relative helicity generally in the 200 to 300 m2/s2
range. This will continue to be favorable for rotating storms this
evening. As a line of strong to severe storms continues to organize,
a few tornadoes will be possible with embedded supercells and bowing
line segments. A tornado threat may also exist with discrete
rotating cells that develop ahead of the line. As the line
progresses eastward, the wind-damage threat will continue, and be
maximized with embedded supercells and bowing line segments. An
isolated large hail threat will exist with supercells but should be
more focused in the southwestern part of the slight where the
strongest instability is located.

Further south into the central Gulf Coast states, from south-central
Mississippi into central Alabama, an isolated severe threat will
continue tonight as low-level flow increases ahead of the cold
front. Moderate instability is forecast to be maintained ahead of
the front as moisture convection continues overnight. As the
southern part of the line moves into this area later tonight, the
potential for wind damage, hail and a few tornadoes is expected to
increase...see MCD 2311.

..Broyles.. 12/10/2023