Mesoscale Discussion 2054
NWS Storm Prediction Center Norman OK
0223 PM CDT Sat Aug 26 2023
Areas affected…Parts of southern MO/IL…northern AR…western
Concerning…Severe potential…Watch possible
Valid 261923Z – 262200Z
Probability of Watch Issuance…40 percent
SUMMARY…Storms capable of producing isolated to scattered damaging
winds will become increasingly possible later this afternoon.
Eventual watch issuance is possible for parts of the region.
DISCUSSION…At 1915 UTC, thunderstorms are gradually increasing in
coverage along a surface boundary from southeast MO into western KY,
within a weakly sheared but strongly unstable environment
characterized by MLCAPE of 2500-3500 J/kg (per recent mesoanalyses).
Strong heating and large PW will support a threat of at least
isolated wet microbursts as these storms sag southward through the
Farther northwest, an MCV is moving southeastward across northwest
MO, with weak convection persisting ahead this feature across
south-central MO. While convection directly influenced by the MCV is
north of the surface boundary described above, a zone of clearing
and diurnal heating/destabilization is noted from
north-central/northwest AR into extreme south-central MO. Storms may
intensify or redevelop as the MCV approaches this region of more
favorable instability. If this occurs, modestly enhanced midlevel
flow associated with the MCV may allow for somewhat organized
clustering and upscale growth, with an attendant threat of scattered
Uncertainty remains regarding the magnitude and coverage of the
severe threat later this afternoon, but watch issuance is possible
if more organized convection appears imminent.
…Please see www.spc.noaa.gov for graphic product…
LAT…LON 37019272 37709128 37768856 37578790 37328762 36868751
36008838 35689075 35859198 35909250 36089289 36379308