Subj : DAY1 Enhanced Risk Cen US To : All From : Dumas Walker Date : Wed Oct 30 2024 08:04 am ACUS01 KWNS 301251 SWODY1 SPC AC 301250 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0750 AM CDT Wed Oct 30 2024 Valid 301300Z - 311200Z ....THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS EASTERN KANSAS...NORTHEAST OKLAHOMA...AND NORTHWEST MISSOURI... ....SUMMARY... Severe thunderstorms capable of producing large hail, damaging wind gusts, and a few tornadoes, are expected today into tonight across the middle Missouri Valley and central/southern Plains, including parts of eastern Kansas and Oklahoma into Missouri. ....Lower Missouri Valley/South-Central Plains... A relatively active severe-weather day is expected regionally, especially late this afternoon into evening, including some southern Plains areas in which there hasn't been severe-weather potential in over a month. The lead portion of an upper-level trough centered over the central/southern Rockies this morning will eject northeastward over the central Plains toward broader parts of the Upper Midwest and Corn Belt. A surface wave will evolve across the eastern Texas Panhandle/northwest Oklahoma vicinity. From this low, an east/southeastward-moving cold front will extend across Kansas into Iowa/Minnesota and eventually Wisconsin/western Missouri by this evening, with this front overtaking a dryline across the southern High Plains. Some severe-weather potential may increase as early as late morning into midday near the cold front across central Kansas into southeast Nebraska and Iowa, with a likely increase in surface-rooted convection and greater severe potential by mid/late afternoon as the front approaches east-central/northeast Kansas and northwest Missouri/southern Iowa. Pre-convective MLCAPE values should reach 500-1250 J/kg within this corridor, with very strong deep-layer southwesterly winds supporting 40-50 kt effective shear and fast east-northeastward storm motions, which will largely parallel the front and its east-southeastward motion. Some severe hail will be possible during the day, but damaging winds and some tornado potential will be more prevalent into late afternoon and evening as a QLCS evolves with embedded bowing segments and potential mesovortices. Farther south, in closer proximity to the surface wave, somewhat more discrete thunderstorm development is expected across south-central/east-central Kansas including the I-35/135 corridors and north-central Oklahoma, with prospects for even more isolated initial supercellular development by around sunset southward into central/southern Oklahoma and North Texas. Surface temperatures in the upper 70s F, combined with mid 60s F dewpoints, will contribute to 1500-2000 J/kg MLCAPE by peak heating. Storms that develop/mature in this environment will likely be supercells in the presence of 45+ effective shear, highlighted by a dramatic strengthening (50-65 kt) of 2-3 km AGL (surface-700 mb) southwesterly winds toward/after sunset. Storm mergers will result in squall line development over time, with a longer duration of more discrete development with southward extent across Oklahoma. A few tornadoes are plausible regionally, and a strong tornado or two could occur, particularly within a couple of hours of sunset. The severe threat should transition to more of a damaging wind threat as the squall line matures, although line-embedded QLCS tornadoes will remain possible this evening, and possibly overnight. ....Southeast Texas... There is some potential that a few stronger/potentially rotating storms could materialize today across the region within a very moist and confluent low-level flow regime. This would be as low-level lapse rates diurnally steepen coincident with a moderate degree of low-level hodograph length and curvature. Modest-strength winds above 2km AGL should limit the sustainability and intensity for any showers/thunderstorms that may exhibit rotating characteristics, and the overall severe potential should remain limited. ...Guyer/Leitman.. 10/30/2024 $$ --- SBBSecho 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (21:1/175) .