SPC Mesoscale Discussion: Severe Potential… Watch Possible

SUMMARY…Thunderstorms along a boundary may pose an isolated severe hail/wind risk this afternoon. Watch issuance is possible.

DISCUSSION…Within a weak low-level warm air advection regime, several thunderstorms have recently intensified along a convectively reinforced boundary across parts of central/northern MS into southern middle TN. The airmass along and south of this boundary will remain moderately unstable through the afternoon, with the 18Z mesoanalysis estimating MLCAPE of 1000-2500 J/kg. This developing convection is well ahead of a southern-stream shortwave trough and related line of thunderstorms across coastal southeast TX. Still, modestly strengthening west-southwesterly winds in the mid/upper levels should support 30-40 kt of effective bulk shear. This shear combined with steep mid-level lapse rates noted on the 12Z sounding from Jackson, MS suggest that isolated large hail will be possible through the afternoon with convection that can remain at least semi-discrete. Strong to locally damaging winds may also be a concern if thunderstorms develop into one or more small line segments as they move east-northeastward. Radar trends will be monitored for any further increase in convective coverage/intensity which may necessitate watch issuance.

Tags: MesoScaleDiscussion

Category: ALL POSTS, MescoScale Discussions