ZCZC SPCSWOMCD ALL ACUS11 KWNS 031735 SPC MCD 031735 MOZ000-ARZ000-TXZ000-OKZ000-031900- Mesoscale Discussion 0336 NWS Storm Prediction Center Norman OK 1235 PM CDT Thu May 03 2018 Areas affected...Portions of north/central/east TX...southeastern OK...western AR...and far southern MO Concerning...Severe Thunderstorm Watch 70... Valid 031735Z - 031900Z The severe weather threat for Severe Thunderstorm Watch 70 continues. SUMMARY...The overall severe threat across WW 70 appears to be decreasing. The need for a downstream watch remains unclear, but does not appear likely in the short term. DISCUSSION...Recent radar trends across central/north TX have shown a general decrease in convective intensity with a loosely organized line of thunderstorms. Better large-scale forcing for ascent associated with an upper trough/low over the central High Plains will remain displaced to the north of the lower MS Valley/Ozarks regions today. The orientation of the squall line is also becoming increasingly parallel to the mean mid-level southwesterly flow, with a corresponding decrease in forward speed noted over the past several hours. Still, modest diurnal heating beneath a mid/upper-level cloud deck ahead of the ongoing line and plentiful low-level moisture should result in a gradual increase in instability this afternoon. A veering/strengthening wind profile with resultant effective bulk shear values around 40-50 kt would also support support some updraft organization. Regardless, the overall severe threat appears relatively marginal given limited low-level convergence and weak instability. The prospect for a downstream watch appears unlikely in the short term, although convective trends will be monitored through the afternoon. ..Gleason.. 05/03/2018 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...SHV...TSA...FWD... LAT...LON 31409816 32089761 32739639 34299546 35059499 36509400 36659332 36609263 36339238 34179294 33089405 31259649 30899718 30969778 31409816 NNNN