Subj : DAY1SVR: Day 1 Convective Outlook To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Aug 05 2025 12:45:32 ACUS01 KWNS 051244 SWODY1 SPC AC 051242 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ....THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ....SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ....Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ...Mosier/Bentley.. 08/05/2025 $$ = = = 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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .