Mesoscale Discussion 0038
NWS Storm Prediction Center Norman OK
1150 AM CST Sat Jan 11 2020
Areas affected...Portions of AL
Concerning...Tornado Watch
12...
13...
Valid 111750Z - 111915Z
The severe weather threat for Tornado Watch 12, 13 continues.
SUMMARY...Greatest potential for tornadoes and damaging
straight-line winds will shift from western into parts of northern
and central AL over the next couple of hours. Some of the tornadoes
could be strong.
DISCUSSION...A squall line has recently consolidated and
strengthened over western AL as large-scale ascent associated with a
northeastward-ejecting upper trough overspreads the central Gulf
Coast states. A couple of embedded low-level circulations have also
recently occurred within the line. One such rotational velocity
signature earlier produced a TDS over Pickens County AL. Very strong
low-level shear exists downstream of the convective line across
northern/central AL, with the VWP from KBMX showing southerly
low-level winds quickly strengthening to over 60 kt in the 0-1 km
layer. Some curvature of the low-level hodograph is supporting
effective SRH around 450-650+ m2/s2 given the northeastward motion
of individual elements embedded within the line. Coupled with a
gradually destabilizing airmass downstream into northern/central AL,
this very favorable kinematic environment will be conducive to
continued damaging straight-line winds and tornadic circulations
embedded within the line. Even with a mainly linear mode, there
remains some potential for a strong tornado or two in the short term
mainly across parts of west-central AL given the exceptionally
strong low-level shear.
..Gleason.. 01/11/2020
...Please see
www.spc.noaa.gov for graphic product...
ATTN...WFO...BMX...HUN...MOB...