BBS: TELESC.NET.BR Assunto: DAY2SVR: Nws Storm Prediction Center Norman Ok De: COD Weather Processor Data: Sat, 23 May 2026 17:27:26 +0000 ----------------------------------------------------------- ACUS02 KWNS 231727 SWODY2 SPC AC 231725 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sat May 23 2026 Valid 241200Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM WESTERN KS INTO CENTRAL/EASTERN NE...SOUTHEAST SD...SOUTHWEST MN...NORTHWEST IA... ...SUMMARY... Strong to locally severe storms are possible from parts of the central Plains into the Upper Midwest, mainly Sunday afternoon and evening. Isolated large to very large hail and localized severe gusts will be possible. ...Central Plains into the Upper Midwest... A mid/upper-level shortwave trough initially over the Upper Midwest will move over the Great Lakes region on Sunday. Broad southerly flow between a surface ridge near the mid MS Valley and a lee trough over the High Plains will result in some moisture return into parts of the central Plains and Upper Midwest, though the magnitude of this moisture return remains somewhat uncertain. Steep midlevel lapse rates and relatively cool midlevel temperatures atop the returning moisture will result in moderate to locally strong destabilization by late afternoon. Broad midlevel height rises are expected across the region, in the wake of the departing shortwave trough. However, guidance suggests that one or more weak midlevel vorticity maxima may aid in at least isolated diurnal thunderstorm development near a weak surface trough/dryline from central NE into southeast SD/southwest MN. Deep-layer flow will remain generally modest, but veering wind profiles and 30-40 kt of effective shear will conditionally support supercells, if surface-based development can be sustained. Large to very large hail and localized severe gusts could accompany any supercell development during the afternoon and evening. A Level 2/Slight Risk upgrade was considered for parts of the region, but due to uncertainties regarding low-level moisture and storm coverage, have opted to maintain a Level 1/Marginal Risk, with a conditional area highlighting very large hail potential, should any sustained supercells develop. ...Southeast/southern Appalachians... Scattered thunderstorm development is again expected across the region, within a moist and uncapped environment. A belt of 20-30 kt midlevel flow to the east of the mid/upper trough across TX will provide modest deep-layer shear, but weak midlevel lapse rates will tend to limit updraft intensity. Locally damaging wind cannot be ruled out with convection across the region, but the organized-severe threat currently appears too limited and nebulous to include probabilities at this time. If a robust MCV emerges from extensive convection near the Gulf Coast, then somewhat more organized severe potential could evolve through the day. ...LA Gulf Coast/Lower MS Valley vicinity... Widespread convection is expected to persist from D1/Saturday into D2/Sunday across parts of the LA Gulf Coast and lower MS Valley, as the nearly stationary mid/upper trough over TX interacts with rich moisture. Generally weak flow and lapse rates are currently expected to limit the organized-severe threat. Any more organized potential for a brief tornado or locally damaging wind would likely be contingent on MCV development, but this scenario remains highly uncertain at this time. ...Lower OH Valley/Allegheny Plateau... Scattered thunderstorms will be possible across parts of the Ohio Valley and Allegheny Plateau during the afternoon, in association with the mid/upper trough moving across the Great Lakes region. Modest midlevel flow will overspread the region and isolated strong storms will be possible, but weak lapse rates and modest buoyancy are expected to limit severe potential. ..Dean.. 05/23/2026 $$ = = = 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: Capitol City Online (1:2320/107) ----------------------------------------------------------- [Voltar]