Morning AFD snippets:
HUN:
Consensus guidance from the global models suggests that the
deepening surface low associated with the mid-level wave will lift
further northeastward into the lower OH Valley by 12Z Sunday and into
IN/OH by 00Z Monday. Conditions appear quite favorable for the
development of an intense QLCS along a surface trough/Pacific cold
front extending southward from the low late Saturday night, based on
orientation of bulk shear vectors w.r.t to the low-level boundary.
This system is expected to affect the local area in the 06-18Z
timeframe on Sunday, and has the potential to be a rather significant
and high-impact severe weather event for the TN Valley, as dewpoints
could rise well into the mid (perhaps upper) 60s beneath a 50-60
knot low-level jet. These parameters should easily support a higher-
end risk both damaging winds and tornadoes.
BMX:
The front will begin to lift back northward as a warm front on
Saturday ahead of another potent shortwave trough moving into the
Southern Plains, resulting in more potential for showers and
thunderstorms, with some stronger activity possible depending on
where the warm front is. This shortwave trough and associated cold
front will continue to move towards the area Saturday night into
Sunday. The overall synoptic setup has been very consistent for the
past 3-4 days for this potential severe weather event though some
model differences and timing differences remain. The latest trends
in the guidance are a bit quicker suggesting the threat could begin
during the overnight hours Saturday night and continuing into
Sunday. A deepening surface low lifting northeastward from Texas to
the Ohio Valley, mid to upper 60s dew points, presence of an EML,
and 40-50 kt southerlies at 850mb veering to 60-70kt southwesterlies
at 500mb are all supportive of a severe threat. Confidence in the
magnitude of the severe threat is somewhat low as the faster timing
does prevent more significant instability from developing, and
details such as convective mode and evolution of upstream convection
will certainly play a role. Still, expect continued fluctuations
in timing the next couple days and some runs have been slower and
more significant. Confidence is high enough to add a tornado
threat to the HWO, with further refinements likely in the coming
days.
