Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Mar 23 2023 19:52:52 ACUS01 KWNS 231952 SWODY1 SPC AC 231951 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Mar 23 2023 Valid 232000Z - 241200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE SOUTHERN PLAINS... ....SUMMARY... Severe thunderstorms capable of large hail will be possible this afternoon into tonight across portions of Texas and Oklahoma. Isolated severe wind gusts or a tornado are possible as well. Little change was needed to the previous outlook. Storms will continue to form in a band near the front from northwest TX across OK and into southern MO through evening. The strongest instability and thus hail threat will exist over northwest TX and southern OK as storms develop, mature, and race northeastward nearly parallel to the surface front. Several rounds of storms are possible as the low-level jet increases this evening. Long hodographs as well as enhanced low-level storm relative flow may aid hail production in some of these storms, especially near and after 00Z. For more information, see mesoscale discussion 310. ...Jewell.. 03/23/2023 ..PREV DISCUSSION... /ISSUED 1130 AM CDT Thu Mar 23 2023/ ....Southern Plains to Ozarks/Lower Ohio Valley... A low-amplitude shortwave trough near the Arizona/Mexico border vicinity and preceding jet streak will transition northeastward toward the southern High Plains by tonight. A southwest/northeast-oriented cold front will continue to advance southeastward across Oklahoma and southern portions of Missouri/Illinois. Beneath a mid-level cap (reference 12z observed soundings), low-level moistening continues to steadily occur within the warm sector with upper 60s/near 70F surface dewpoints increasingly prevalent across central/east Texas toward the ArkLaTex. Warm-sector cloud cover remains semi-prevalent at late morning, but visible satellite imagery does reflect a gradual scattering of stratus across central/east Texas. Given warm-sector capping and forcing for ascent initially focused near and on the cool side of the boundary, scattered to eventually numerous thunderstorms are expected to develop by around mid-afternoon initially across Oklahoma near the front. Any development that can mature along/ahead of the front through late afternoon/early evening, without getting undercut by it, may pose a more consequential large hail risk, along with the potential for damaging wind gusts and possibly some tornado risk. Such wind/tornado potential may be modestly higher across far eastern Oklahoma into western Arkansas/far southwest Missouri if a weak surface wave materializes along the front. Overall, forecast soundings suggest favorable deep-layer shear for supercells, with intense mid-level winds contributing to effective-shear magnitudes in the 55-70 kt range. With 60s F dewpoints pervasive in the moist sector, peak/preconvective MLCAPE around 1500 J/kg should be common from the Ozarks southwestward, diminishing below 1000 J/kg toward southern Indiana and locally reaching 2000 J/kg in parts of southwestern Oklahoma and northwest Texas. Farther southwest, a more isolated/conditional deep convective potential will exist over northwest Texas near the front/dryline intersection. Any persistent thunderstorms will develop in a greater instability/shear parameter space will have the potential to become supercells and offer significant/2+ inch diameter hailstones. As the front(s) overtake the dryline later this evening and overnight, the combined lift may overcome EML-related CINH enough to backbuild the convection into parts of west-central and perhaps southwest Texas. At least isolated thunderstorms (which also may become supercellular and offer substantial hail) are possible as far south as the Rio Grande. $$ = = = 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) .