Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Mar 23 2023 05:55:48 ACUS01 KWNS 230555 SWODY1 SPC AC 230554 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1254 AM CDT Thu Mar 23 2023 Valid 231200Z - 241200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE EDWARDS PLATEAU TO THE RED RIVER AND INTO THE NORTHERN OZARKS... ....SUMMARY... Thunderstorms capable of hail, some very large, are possible Thursday afternoon through Friday morning across parts of the southern Great Plains. ....Synopsis... A shortwave trough, seen on morning water-vapor imagery across southern California will traverse the Southwest this morning and move to the TX/OK Panhandle by 06Z Friday. In advance of this shortwave trough, a surface low will develop across far West Texas and deepen gradually through the day. A cold front which extends from central Kansas to the southern tip of Lake Michigan this morning will move slowly south through the day, and eventually will stall early Friday morning as low-level flow strengthens in response to the developing surface low. ....Southern Plains... The eastward-advancing mid-level trough will lead to weak mass response across the southern Plains as early as midday Thursday. This will result in backing/strengthening 850mb flow and associated isentropic ascent. Thunderstorm activity is expected near or slightly to the cool side of the frontal boundary across Oklahoma during the early afternoon period. Moderate instability, steep mid-level lapse rates, and long/straight hodographs will support supercells capable of large to very large hail. The majority of convection-permitting guidance indicates thunderstorm activity will be anafrontal and thus elevated. This is the most likely solution since the front should be the primary initiating source, and the mean wind will remain parallel to the frontal orientation. Any storms along or ahead of this front would pose a brief tornado threat. Additional storms are expected after 04Z as weak DCVA ahead of the approaching mid-level shortwave trough overspreads the warm sector. Storms will be possible along the entire dryline from the Rio Grande to southwest Oklahoma. However, this shortwave trough will be dampening as it moves east, and therefore, its influence is unknown. At least isolated supercell coverage is expected in the 03Z to 09Z period across central Texas into southern Oklahoma. Large hail will be the primary threat with this activity. Despite the strengthening low-level jet, increasing inhibition and weak flow between 1-2 km will be a limiting factor to the tornado threat, although it cannot be ruled out. ....The Ozarks into southern Illinois/Indiana... Early morning thunderstorms across Missouri and Illinois will continue east across Indiana and Ohio by mid-day Thursday, but should remain sub-severe due to limited instability with eastward extent. Elevated thunderstorms which develop in Oklahoma early Thursday afternoon will continue northeast on the cool side of the front through the afternoon and evening, with additional development expected as the low-level jet strengthens further. A southward-moving cold front and storm motion parallel to the surface front should lead to mostly anafrontal/elevated convection. However, on the mesoscale, any storms which remain latched to the front could pose a threat for a tornado. ...Bentley.. 03/23/2023 $$ = = = 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) .