ZCZC SPCSWOMCD ALL ACUS11 KWNS 071311 SPC MCD 071311 INZ000-KYZ000-ILZ000-TNZ000-MOZ000-ARZ000-MSZ000-071415- Mesoscale Discussion 0089 NWS Storm Prediction Center Norman OK 0711 AM CST Thu Feb 07 2019 Areas affected...central and northeast AR...far western TN...southeast MO...western KY...southern IL...far southwest IN Concerning...Severe Thunderstorm Watch 4... Valid 071311Z - 071415Z The severe weather threat for Severe Thunderstorm Watch 4 continues. SUMMARY...Isolated severe gusts (60-70 mph) and perhaps a brief/weak tornado (75-110 mph) are possible this morning as a squall line moves east towards the MS River. A replacement of severe thunderstorm watch 4 over north-central AR combined with including areas farther east and northeast is being considered. DISCUSSION...Radar imagery shows a squall line from southwest AR northeast to the middle part of the AR/MO border. Surface observations downstream of the squall line indicate temperatures range from near 70 degrees F in central AR to the lower 60s near the MS/OH River confluence. Strong low-level moisture transport is occurring over the MS Valley and dewpoints range from the middle 60s near I-40 to the lower 60s north in western KY. The 12z LZK raob showed 900 J/kg MLCAPE with a very strong and veering low-level wind profile beneath a 125-kt upper speed max. Given the sufficient buoyancy and the very strong shear profile, it appears a risk for wind damage and perhaps a tornado will continue through the morning with intensification of the squall line in the form of bowing segments becoming increasingly probable. Some risk for a tornado (max wind speed 75-110 mph based on experimental guidance) may accompany the strongest/longer-lived mesovortices. ..Smith/Grams.. 02/07/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PAH...MEG...LSX...LZK...SGF... LAT...LON 35059272 36589117 38508884 38298780 37948719 36778844 35548958 34919011 34339179 34389228 35059272 NNNN