ZCZC SPCSWOMCD ALL ACUS11 KWNS 290321 SPC MCD 290321 MOZ000-ARZ000-290415- Mesoscale Discussion 0567 NWS Storm Prediction Center Norman OK 1021 PM CDT Sun Apr 28 2024 Areas affected...northern Arkansas into southern Missouri Concerning...Tornado Watch 159... Valid 290321Z - 290415Z The severe weather threat for Tornado Watch 159 continues. SUMMARY...Severe threat continues. Local watch extension past 04z may be needed. DISCUSSION...Thunderstorm activity continues across portions of Missouri and Arkansas. Mesoanalysis indicates surface based instability has become limited, though MLCAPE around 500-1,000 J/kg continues to advect in from the southeast. This activity is also located along the edge of the axis of a 40 kt low-level jet, which is providing ample shear for maintaining an organized severe threat. As such, a threat of damaging winds may persist through the short term. Further south, a supercell has tracked from the OK/AR border into western AR and continues to maintain organization with periods of increase in rotation strength. WW159 may need to be expanded in time and spatial extent to account for potential risk with this storm and for additional transient supercell activity across northern Arkansas that may move into southern Missouri. ..Thornton/Smith.. 04/29/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...TSA... LAT...LON 36689327 37019308 37319289 37429242 37239182 37049165 36519156 36059267 35789312 35639333 35659370 35939371 36689327 NNNN