Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Mar 13 2024 05:45:03 ACUS01 KWNS 130544 SWODY1 SPC AC 130543 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1243 AM CDT Wed Mar 13 2024 Valid 131200Z - 141200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY... ....SUMMARY... Severe thunderstorms, associated with large to very large hail, wind damage and a few tornadoes, are expected today across parts of the central Plains and lower Missouri Valley. Isolated severe storms may occur across parts of the southern Plains. ....Central Plains/Lower Missouri Valley... An upper-level low will move into the Intermountain West today, as a 70 to 90 knot mid-level jet rounds the base of the system. In response, a surface low will deepen across far southwest Kansas and the Oklahoma Panhandle. To the east of the surface low, strong moisture advection will occur. By afternoon, surface dewpoints are expected to reach the mid to upper 50s F over eastern Kansas and much of Missouri, where an east-to-west corridor of moderate instability is forecast to develop. A dryline will likely setup further west over south-central Kansas. Scattered convective initiation appears likely along and near the instability axis by late afternoon, with storm coverage expanding markedly during the early evening. Multiple clusters of organized thunderstorms will likely develop over parts of the central Plains and lower Missouri Valley. In response to the approaching mid-level jet, an area of very steep mid-level lapse rates is forecast to spread northeastward into the central Plains during the afternoon. RAP forecast soundings near the instability axis by 00Z/Thursday have MLCAPE in the 2000 to 2500 J/kg range with 700-500 mb lapse rates around 8 C/km. This thermodynamic environment, along with 40 knots of 0-6 km shear will be favorable for supercells with large hail. Hailstones of greater than 2 inches in diameter will be possible with the more dominant and intense supercells. In addition, 0-3 km storm-relative helicity is forecast to be near 300 m2/s2 suggesting that a tornado threat will also likely develop. The greatest tornado threat is expected in the early evening as the low-level jet strengthens. Wind damage will also be possible. ....Southern Plains... Strong moisture advection will take place today across the southern Plains, as surface dewpoints increase into the 60s F across north Texas and eastern Oklahoma. A dryline will develop along the western edge of this moist airmass during the afternoon. RAP forecast soundings near the moist axis increase MLCAPE to around 2000 J/kg by afternoon, but have a capping inversion over most of the southern Plains. This should keep convective initiation very isolated. RAP forecast soundings by late afternoon to the east of the dryline have 0-6 km shear in the 50 to 60 knot range. The deep-layer shear and instability will easily support supercell development with any updraft that can grow upscale as the cap becomes weaker in the late afternoon. If an organized cell can develop and persist, isolated large hail, strong gusts and a marginal tornado threat would be possible. However, this threat is expected to be highly conditional. ...Broyles/Thornton.. 03/13/2024 $$ = = = 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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .