Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
970 ACUS02 KWNS 301740 SWODY2 SPC AC 301739 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1239 PM CDT Thu May 30 2024 Valid 311200Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM CENTRAL/SOUTHEAST TEXAS INTO THE MID MISSISSIPPI VALLEY AND ACROSS THE CENTRAL HIGH PLAINS... ...SUMMARY... One or two organized clusters of storms may evolve by Friday morning into afternoon and pose a risk for severe wind and hail continuing across parts of the southern Great Plains into lower Mississippi Valley, Texas Gulf coast and Deep South Texas by Friday evening. Additional storms are expected across the central High Plains with a threat for large hail and severe wind gusts. Finally, storms are possible across the Mid-Mississippi Valley with the potential for a tornado or two. ...Synopsis... On Friday, a positively tilted mid-level trough will exit the Northeast US with a ridge building in its wake. Meanwhile, a broad mid-level trough will be present across the central CONUS with a convectively enhanced mid-level trough developing and slowly moving across Oklahoma and into Arkansas. A weak surface low/MCV may be present with this feature as it moves east through the afternoon and could provide a focus for a localized threat for a tornado or two. ...Central Texas to the western Gulf Coast... Considerable uncertainty remains with the presence and evolution of morning convection across Texas. There seems to be some consistency synoptically and with most CAM guidance for elevated convection to develop around 12Z in the Lubbock to Abilene vicinity. However, there is considerable uncertainty how this convection develops from here. A MCS from Thursday evening/overnight thunderstorms is expected to expand through the overnight period and perhaps maintain intensity to the Gulf Coast. Wherever the composite outflow boundary stalls from this convection, likely from the Edwards Plateau northwest to near San Angelo will likely be very unstable and strongly sheared with supercells capable of primarily large hail and severe wind gusts. The greater question will be how much recovery can occur north of this outflow boundary in the wake of morning convection. Therefore, the severe threat across central into southeast Texas is more conditional and may need modified once Day 1 convective evolution becomes more clear. ...Mid-Mississippi Valley... A MCV/surface low will traverse slowly across Oklahoma and Arkansas through the day on Thursday into a moist airmass. Forecast models which seem to correctly resolve this MCV show shear which would be favorable for mini supercells and low-level hodographs that could support a tornado or two Thursday afternoon/evening, particularly where some heating can occur. ...Central High Plains... Weak upslope flow and terrain circulations will support thunderstorm development across the Front Range by early afternoon. These storms will eventually move into an increasingly unstable airmass across the Plains with 1000 to 1500 J/kg MLCAPE and around 40 knots effective shear and mid-to-upper level backing flow. This will support splitting supercells with a threat for both large hail and damaging wind gusts. The chaotic storm motion of both the left and right moving storms should lead to relatively quick upscale growth into one or more clusters with an increasing severe wind threat as storms move east. ..Bentley.. 05/30/2024 $$