SPC MD 254

MD 0254 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR MUCH OF CENTRAL/EASTERN ARKANSAS…NORTHWESTERN MISSISSIPPI…WESTERN AND MIDDLE TENNESSEE AND ADJACENT PORTIONS OF SOUTHERN KENTUCKY

Mesoscale Discussion 0254
NWS Storm Prediction Center Norman OK
0129 PM CDT Sun Mar 23 2025

Areas affected...much of central/eastern Arkansas...northwestern
Mississippi...western and middle Tennessee and adjacent portions of
southern Kentucky

Concerning...Severe potential...Watch possible 

Valid 231829Z - 232100Z

Probability of Watch Issuance...60 percent

SUMMARY...Scattered intensifying thunderstorm development appears
increasingly probable through 3-6 PM CDT.  This may include a few
supercells capable of producing large hail, and perhaps the risk for
a tornado or two across western into middle Tennessee and adjacent
portions of northwestern Mississippi/southern Kentucky.  Trends are
being monitored for one or more severe weather watches.

DISCUSSION...Latest model output suggests that the primary short
wave trough is beginning to pivot northeast of the lower Missouri
Valley through the upper Mississippi Valley.  This is preceded by a
less prominent mid-level perturbation, but strongest
lower/mid-tropospheric wind fields, forecast to continue
east-northeastward through the Ohio Valley.  It appears that this
will include an intensifying southwesterly jet core, in excess of 50
kt around 850 mb, across and northeast of the Kentucky Bluegrass. 
Within a moistening pre-cold frontal environment trailing this
feature, Rapid Refresh forecast soundings indicate that flow around
850 mb will tend to veer, but may be maintained in excess of 30-40
kt across western into middle Tennessee through mid to late
afternoon, while low-level hodographs undergo more substantive
shrinking into central/southern Arkansas.

Still, beneath a capping elevated mixed-layer across the Ark-La-Tex
into Mid South, the low-level moisture return, coupled with
increasing insolation, is contributing to substantive boundary-layer
destabilization.  It appears that this may include CAPE on the order
of 2000 to 1000 J/kg (from southwest to northeast), in the presence
of weakening mid-level inhibition, within the next few hours.

As the leading edge of cooling aloft gradually overspreads the Mid
South toward Ark-La-Tex, guidance indicates that the initiation of 
scattered, but increasing, thunderstorm development is probable by
20-23Z.  Stronger storms will pose a risk for producing large hail. 
Where low-level hodographs remain more enlarged and clockwise
curved, a couple of supercells with potential to produce tornadoes
may not be out of the question across northwestern Mississippi
through western and middle Tennessee and adjacent portions of
southern Kentucky.

..Kerr/Hart.. 03/23/2025

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...LMK...OHX...HUN...PAH...MEG...JAN...LZK...SHV...

LAT...LON   35689218 36519074 36788681 35588724 34818801 34149045
            33839197 33859373 35089314 35689218 

Read more