Pretty quiet for a severe weather threat were the models have been creeping higher and highers portions of GA/AL now in enhanced risk.
Gotta admit this one snuck up on me. The talk I had heard all week was this risk area was there out of a course of least regret. Did not expect to wake up to an enhanced risk but here we are.
..Synopsis...
A positively tilted mid-level trough and associated surface low will
traverse the OH/TN Valley areas today as a surface cold front sweeps
across the Southeast. Low-level moisture will stream north from the
Gulf of Mexico ahead of the advancing front. The moisture will be
overspread by a seasonably strong low-level jet and cold
temperatures aloft, providing enough buoyancy, shear, and deep-layer
ascent to support a threat for several strong to potentially severe
thunderstorms, especially from the TN Valley into the Southeast this
afternoon into the evening hours.
...TN Valley into the Southeast...
Scattered strong to potentially severe thunderstorms should be
ongoing at the beginning of the period across the TN Valley ahead of
the surface low. These storms should be fueled by at least some
elevated instability, with strong deep-layer shear and 7-8 C/km
mid-level lapse rates promoting an isolated large hail threat in
association with transient supercell structures. With diurnal
heating, strong thunderstorms should continue to develop along the
cold front in MS by morning and progress eastward through the
afternoon.
The 00Z LIX observed sounding shows mid 60s F surface dewpoints and
near 8 C/km mid-level lapse rates. These steeper lapse rates should
continue to overspread the Gulf Coast states given strong westerly
700-500 mb flow. Low-level moisture should remain modest (i.e. low
60s F surface dewpoints), but the steeper lapse rates should
compensate to support 500-1000 J/kg of skinny MLCAPE. A 40-50 kt
low-level jet overspread by even stronger westerlies aloft should
result in elongated hodographs, with some curvature in the surface-3
km layer. As such, a mix of line-embedded transient supercells and
bowing segments are expected along the front. Modestly dry 850-500
mb air may promote efficient downward momentum transport through the
strong low-level jet to promote a damaging/severe wind gust threat,
hence the Category 3/Enhanced risk across central AL/GA. Large hail
may initially accompany the stronger, sustained updrafts given the
steep mid-level lapse rates. Given the modest low-level moisture,
the tornado threat appears a bit more conditional, though at least a
few brief tornadoes may still develop in either embedded QLCS
circulations, or any discrete, sustained storms ahead of the line.