Subj : DAY2SVR: Nws Storm Prediction Center Norman Ok To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jun 27 2023 06:02:58 ACUS02 KWNS 270602 SWODY2 SPC AC 270601 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0101 AM CDT Tue Jun 27 2023 Valid 281200Z - 291200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHEAST AND UPPER MISSISSIPPI VALLEY... ....SUMMARY... An isolated wind-damage threat is expected on Wednesday morning across parts of the central Gulf Coast states. Isolated large hail and wind damage may occur in the upper Mississippi Valley. Marginally severe wind gusts and hail will also be possible in parts of the central and northern High Plains. ....Central Gulf Coast States... A linear MCS is forecast to be ongoing at the start of the period on Wednesday in far eastern Arkansas. The MCS, or remnant convection associated with the MCS, is expected to continue after daybreak. There is some uncertainty concerning the exact track of the MCS. At this time, the models suggest that the convective system will track south-southeastward across northern and central Mississippi. Isolated severe wind gusts will be possible ahead of this line segment. There is also some potential for afternoon severe storms as convection redevelops along the instability axis. ....Upper Mississippi Valley... An anticyclone will remain in place across the south-central U.S. on Wednesday. To the north of the anticyclone, a subtle shortwave trough is forecast to move eastward into the upper Mississippi Valley. At the surface, a cold front is forecast to move southeastward across the northern Plains, as a surface low moves across Minnesota. An axis of maximized low-level moisture with surface dewpoints in the mid 60s F, is expected to be in place ahead of the low from eastern Minnesota southward into east-central Iowa. In response, moderate instability is forecast to be in place by late morning. Convective initiation appears likely along the northern edge of the stronger instability in central and eastern Minnesota during the afternoon. Thunderstorms should develop southward across southeastern Minnesota during the late afternoon and early evening, with isolated storms possible across parts of Iowa. NAM forecast soundings at 00Z/Thursday south of Minneapolis have MLCAPE near 3000 J/kg, 0-6km shear of 40 to 45 knots and 700-500 mb lapse rates near 8.0 C/km. This will support supercells with a potential for large hail and wind damage. An isolated tornado threat may also develop as a 30 to 40 knot low-level jet strengthens during the early evening. The main uncertainty with this event is convective coverage. At this time, the high-resolution models are forecasting enough convection on Thursday for the addition of a small slight risk. ....Central High Plains... An anticyclone will be present across the south-central U.S. on Wednesday, as southwest mid-level flow remains from the Four Corners region into the central Rockies. At the surface, backed upslope flow will likely help maintain an axis of maximized low-level moisture across the central High Plains. As surface temperatures warm during the day, scattered thunderstorms are expected to form in the higher terrain of eastern Wyoming. This convection will likely spread eastward into southwestern South Dakota and western Nebraska. Isolated damaging wind gusts and hail will be possible as instability peaks in the late afternoon. ...Broyles.. 06/27/2023 $$ = = = 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) .