Mesoscale Discussion 0322
NWS Storm Prediction Center Norman OK
1110 AM CDT Wed Apr 07 2021
Areas affected...Parts of eastern/northeastern Texas through western
Arkansas
Concerning...Severe potential...Watch likely
Valid 071610Z - 071815Z
Probability of Watch Issuance...80 percent
SUMMARY...The initiation of strong to severe thunderstorms appears
possible as early 1-2 PM CDT. This may, at least initially, include
discrete supercells, before a squall line tends to evolve, and a
risk for tornadoes, one or two of which could be strong.
DISCUSSION...Cloud cover is slowing moist, warm sector
boundary-layer destabilization, but it appears the air mass is
already potentially moderately unstable as the significant upstream
short wave trough begins to take on a neutral to negative tilt
across the central Great Plains. Downstream of the base of this
troughing, beneath increasingly difluent mid/upper flow,
considerable model output suggests that erosion of inhibition
associated with capping elevated mixed-layer air, coupled with at
least some further boundary-layer warming, will allow for the
initiation of thunderstorm development as early as 18-19Z.
Initially this may be largely discrete, and scattered, but focused
within a zone of enhanced low-level convergence along an eastward
advancing cold front.
With the environment becoming characterized by wind profiles with
strong deep-layer shear and sizable, clockwise-curved low-level
hodographs, in the presence of a deep moist boundary-layer, it
appears conducive to supercells capable of producing tornadoes.
This includes potential for a strong tornado or two, though the
overall tornado potential could be mitigated somewhat by relatively
modest high-level flow and the tendency for upscale convective
growth along the cold front through the afternoon.
..Kerr/Hart.. 04/07/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LZK...SHV...TSA...HGX...FWD...EWX...