MD 0322 CONCERNING SEVERE POTENTIAL…WATCH LIKELY FOR PARTS OF EASTERN/NORTHEASTERN TEXAS THROUGH WESTERN ARKANSAS

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...

LAT...LON   35259406 35569269 32319337 30209670 32799545 34259449
            35259406 

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