Subj : DAY2SVR: ENHANCED RISK KS To : All From : Dumas Walker Date : Sat May 18 2024 09:06 am ACUS02 KWNS 180552 SWODY2 SPC AC 180550 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1250 AM CDT Sat May 18 2024 Valid 191200Z - 201200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF WESTERN AND CENTRAL KANSAS... ....SUMMARY... Severe thunderstorms are most likely across parts of Kansas Sunday afternoon and evening. Significant damaging gusts, large to very large hail, and a few tornadoes all appear possible. ....NE/KS/OK... A weak upper shortwave impulse over NE Sunday morning will quickly lift northeast. Some convection may be ongoing across NE/KS during the morning, but is forecast to quickly weaken/shift east. This early activity may suppress severe potential across northeast NE during the afternoon as airmass recovery is uncertain. By afternoon, another upper shortwave trough is forecast to eject from the southern/central Rockies into KS, and then the Lower MO Valley by Monday morning. This secondary shortwave trough will be the focus for the primary severe risk during the afternoon/evening. A surface dryline is forecast to extend southward from near the NE/KS/CO border into western KS and then near the OK/TX border. To the east of the dryline, dewpoints into the low/mid 60s are expected across OK into central/eastern KS (somewhat lower across northern KS and southern NE). Very steep midlevel lapse rates (greater than 8 C/km) will be in place. Capping will suppress convection until mid/late afternoon, when large-scale ascent increases amid strong heating and continued warm/moist advection. High-based storms along the dryline will initially pose a risk of large hail and damaging gusts. Forecast guidance (including HREF and CAMs) show a strong signal for upscale growth into an intense bow is possible across KS. Upscale growth is possible via consolidating outflow and an increasing low-level jet during the late afternoon/early evening. Significant gusts will be possible if this scenario evolves as expected. Large to very hail and a few tornadoes also will be possible. Hail greater than 2 inches in diameter will be possible early in convective evolution, but eastward extent of this risk is uncertain and dependent on storm mode. Severe potential southward along the dryline into western OK is more uncertain and conditional. If a storm can develop and be maintained, all severe hazards would be possible, particularly very large hail and damaging gusts. ....SD vicinity... Southerly low-level flow will transport mid/upper 50s F dewpoints northward into northern NE/SD and southern ND. A cold front is forecast to develop eastward during the late Sunday afternoon into Sunday night. Steep midlevel lapse rates will be in place, but an EML will likely limit a greater severe risk. Nevertheless, MUCAPE to around 1500 J/kg will support elevated convection ahead of the cold front. Isolated hail will be the main risk. However, if an organized line of storms can develop, some gusty winds also are possible. ....Lower MO Valley toward the Mid-MS Valley... Convection from NE/KS may dissipate over the area during the morning. However, a warm front is expected to slowly lift northward through the day, allowing from some airmass recovery and destabilization. Convection may redevelop near this boundary during the afternoon. This activity may produce marginally severe hail and gusty winds. ....FL... An upper trough from the Mid-Atlantic to the northern Gulf will shift east over the Atlantic on Sunday. A belt of enhanced west/southwesterly flow (30-40 kt at 700 mb) will overspread the FL peninsula ahead of the trough. Mid to upper 60s F surface dewpoints and strong heating will contribute to MLCAPE values around 1500-2500 J/kg. Steep low-level lapse rates will support isolated strong gusts in water-loaded downdrafts. Elongated/straight forecast hodographs and modest midlevel lapse rates (6.5-7 C/km) suggest isolated large hail also is possible. Effective shear around 30 kt suggests organized updrafts may be somewhat transient. If confidence increases regarding coverage of organized severe convection, higher probabilities may be needed in subsequent outlooks. ...Leitman.. 05/18/2024 $$ --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (21:1/175) .