Valid 261630Z – 271200Z
…THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PARTS OF THE
Locally damaging wind gusts and a brief tornado are possible through
early evening across parts of the Southeast States.
A small convective cluster is ongoing just north of a deepening
surface cyclone over northeast MS. While instability was meager as
sampled earlier by the 12Z Jackson, MS sounding and recent AMDAR
soundings near Memphis and Nashville, a plume of upper 60s surface
dew points does extend into western TN. It is plausible that this
convective cluster may persist northward into western TN through
early afternoon before instability becomes negligible with northern
extent. Locally strong gusts should be the main hazard.
Well southeast of the cyclone, a low-topped convective band is
ongoing along a sharp cold front across southwest AL with somewhat
higher tops and lightning discharge over the northern Gulf. Despite
low to mid 70s surface dew points, poor lapse rates above the
boundary layer will be a limiting factor to deeper convection
inland. Low-level wind profiles per area VADs have begun to weaken
as the surface cyclone and associated shortwave trough rapidly eject
north-northeast towards the Midwest and Great Lakes. This suggests
low probability tornado/wind potential will probably only exist
through late afternoon in the FL Panhandle.
Additional low-topped convection may attempt to develop between the
coastal band along the front and the cluster near the surface
cyclone. Modest boundary-layer heating is occurring amid some cloud
breaks across central and southern AL. This should support a
conditional threat for a brief tornado and locally damaging wind
later this afternoon into early evening across parts of
east-central/northeast AL into northwest GA.