000 ACUS02 KWNS 170532 SWODY2 SPC AC 170530 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Wed Aug 17 2022 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF COASTAL/EAST TEXAS INTO THE SOUTHEAST...AND A SMALL PORTION OF THE CENTRAL PLAINS... ...SUMMARY... Isolated strong to severe thunderstorms may occur Thursday over parts of east/coastal Texas into the Southeast, and a small portion of the central Plains. ...Coastal/East Texas into the Southeast... A surface front should remain draped across parts of the southern Plains into the Southeast on Thursday. These regions will be on the southern extent of any appreciable mid-level flow associated with an upper trough that will remain over the central/eastern states. Still, a rather moist low-level airmass, with surface dewpoints generally in the low to mid 70s, will likely remain in place along and south of the front. Moderate instability characterized by MLCAPE ranging from 2000-3000+ J/kg should develop across these regions where robust diurnal heating can occur. There is still some uncertainty in where the greatest instability will develop, with the potentially stabilizing influences of convection ongoing Thursday morning, as well as lingering cloudiness. Still, there is enough of a convective signal in most guidance for two areas of at least scattered convection that should develop along/south of the front Thursday afternoon. One area extends from parts of coastal/east TX into the central Gulf Coast states. This region will have very weak deep-layer shear, but some clustering of convection may still occur as thunderstorms spread east-southeastward to the coast through early Thursday evening. Isolated damaging winds should be the main threat with this activity as low-level lapse rates diurnally steepen. The other area of interest extends from parts of north FL into southern/coastal GA and vicinity. A weak, convectively enhanced mid-level perturbation on the southern periphery of the upper trough may move across this region through the day. The presence of 20-30 kt of deep-layer shear and moderate instability ahead of a front should encourage modest updraft organization. Mainly multicells capable of producing isolated damaging winds should be the main severe threat as thunderstorms spread eastward to/off the Atlantic Coast through early Thursday evening. Some marginally severe hail may also occur with any convection that can remain semi-discrete. ...Central Plains... Large-scale upper troughing is forecast to persist over much of the central and eastern CONUS on Thursday. A low-amplitude perturbation embedded within this upper trough should develop southward across the northern/central Plains through Thursday evening. Modest low-level moisture should be in place ahead of a cold front that should also move southward across the same regions. Instability may remain somewhat limited, with MLCAPE generally 500-1500 J/kg. But, enough enhancement to the mid-level north-northwesterly flow should be present to support around 25-35 kt of effective bulk shear and some updraft organization. A mix of multicells and perhaps marginal supercells may develop along or just ahead of the front Thursday afternoon, with an isolated severe threat focused mainly over parts of NE and vicinity. Both strong to severe winds and marginally severe hail appear possible with the more robust cores, before convection weakens Thursday evening with the loss of daytime heating. ..Gleason.. 08/17/2022 $$