Mesoscale Discussion 2203
NWS Storm Prediction Center Norman OK
0516 PM CDT Thu Sep 28 2023
Areas affected…portions of western Tennessee
Concerning…Severe potential…Watch unlikely
Valid 282216Z – 282315Z
Probability of Watch Issuance…5 percent
SUMMARY…A couple instances of severe hail or wind may occur with
one of the stronger storms. The severe threat should remain sparse
and a WW issuance is not expected.
DISCUSSION…Isolated thunderstorms have experienced an uptick in
intensity over the past couple of hours along a baroclinic zone.
Steep low-level lapse rates atop upper 60s F dewpoints are
contributing to 1500+ J/kg MLCAPE. Veering with height of the
tropospheric wind fields is supporting 30-40 kts of effective bulk
shear, which is encouraging the organization of transient supercell
thunderstorms. Given poor mid-level lapse rates/marginal instability
and modest vertical wind shear, the severe threat should be limited
to a couple instances of severe hail/wind with the stronger, more
persistent supercell storms. Given the isolated nature of the severe
threat, a WW issuance is not expected.
…Please see www.spc.noaa.gov for graphic product…
LAT…LON 36398944 36658897 36558853 36318831 35908816 35428825
35228855 35228889 35468924 36058952 36398944