Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Jun 09 2023 17:31:38 ACUS02 KWNS 091731 SWODY2 SPC AC 091729 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Jun 09 2023 Valid 101200Z - 111200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF NORTH/CENTRAL TEXAS INTO THE ARKLATEX REGION... ....SUMMARY... Multiple clusters of strong/severe thunderstorms may develop across parts of the southern Great Plains, ArkLaTex, and lower Mississippi Valley on Saturday. Damaging wind gusts and isolated hail will be possible across the ArkLaTex into the lower Mississippi Valley, with some potential for very large hail, severe gusts, and a tornado or two across parts of north and central Texas. ....Synopsis... On the large scale, a seasonably deep upper-level trough will shift slowly eastward across the eastern Pacific and western CONUS on Saturday, as a notable upper ridge remains in place from the northern High Plains into the Canadian Prairies, and a longwave trough generally remains in place from the Great Lakes into much of the eastern CONUS. At the surface, a cold front will move through the northern and eventually central Plains, with a frontal wave expected to move southeastward somewhere across NE/KS, and another weak surface wave potentially developing near a surface trough across the southern High Plains. ....ArkLaTex/ArkLaMiss regions... A thunderstorm cluster or loosely organized MCS may be ongoing somewhere across OK/north TX/western AR Saturday morning, aided by low-level warm advection. Some rejuvenation and/or redevelopment along the gust front will be possible by late morning into early afternoon into parts of the ArkLaTex/ArkLaMiss regions, as rather strong heating and destabilization occurs downstream of any morning convection. Scattered damaging winds and isolated hail will be possible if this scenario does evolve on Saturday. Any storm cluster or MCS would likely tend to lose organization as it moves toward the lower MS Valley, due to weaker deep-layer shear and low-level inflow with eastward extent, though some damaging wind threat could persist with any remnant cluster into central/southern MS. A few strong multicells could also develop across parts of AR/MS ahead of any outflow-driven cluster during the afternoon, within a warm, buoyant, and uncapped environment. ....Parts of north/central into east TX... Confidence is rather high regarding the development of severe thunderstorms somewhere across central/north TX Saturday afternoon, as a low-amplitude southern-stream shortwave trough moves across the region and an outflow boundary potentially spreads into the area from the north. Considerable uncertainty remains, however, regarding the position of the outflow boundary (if any) during the afternoon. In general, scattered storm development will be possible near any outflow boundary, and also along a diffuse surface trough/dryline that may gradually mix eastward during the afternoon. Strong heating of a favorably moist environment will support strong to locally extreme buoyancy near/south of any outflow boundary, and along/east of the weak surface trough/dryline. Midlevel west-northwesterly flow will not be overly strong, but sufficient to support 30-40 kt of effective shear (greater where surface winds are locally backed), and initial development may quickly evolve into supercells with an attendant threat of very large hail and localized severe gusts. A tornado or two also cannot be ruled out, depending on mesoscale details regarding the orientation of any outflow boundary and the extent of modification on the cool side of the boundary. With time, storm clustering may result in some upscale growth, with a threat of damaging winds and embedded hail spreading south-southeastward Saturday evening into portions of central/southeast TX. Storms will eventually move into a region of weaker deep-layer shear and increasing MLCINH, but some severe threat may reach as far as the upper TX coast Saturday night. ....Central Plains... Scattered to numerous thunderstorms are expected across parts of the central Plains Saturday afternoon and evening, within a post-frontal regime across the High Plains, and along/ahead of the cold front from central/eastern NE/KS into western IA/MO. Deep-layer flow/shear will generally remain rather weak, with some uncertain potential for locally enhanced shear near any MCVs. One or more weakly organized clusters may eventually evolve and move east/southeastward with time across the region, with an attendant threat of isolated hail and localized severe gusts. ...Dean.. 06/09/2023 $$ = = = To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .