ZCZC SPCSWOMCD ALL ACUS11 KWNS 122023 SPC MCD 122023 MOZ000-NEZ000-KSZ000-IAZ000-SDZ000-122230- Mesoscale Discussion 0775 NWS Storm Prediction Center Norman OK 0323 PM CDT Fri May 12 2023 Areas affected...Northeast Nebraska to northeast Kansas Concerning...Tornado Watch 215... Valid 122023Z - 122230Z The severe weather threat for Tornado Watch 215 continues. SUMMARY...The severe threat across WW 215 will continue for the next several hours. The tornado threat will likely be maximized in the near-term across northeast Nebraska, while the severe threat is expected to increase across eastern Nebraska to northeast Kansas over the next couple of hours as storms mature. DISCUSSION...Over the past 1-2 hours, regional reflectivity/velocity imagery has shown several organized splitting supercells developing along and ahead of a northward migrating dryline. Splitting supercells have been observed within the arcing band of convection, with the right moving cells exhibiting strong mesocyclones capable of producing tornadoes (with a few tornadoes already reported). This is likely due to enhanced low-level SRH along a subtle confluence axis noted in recent surface observations. The storms associated with recent tornado reports appear to be residing along this boundary as they move to the northwest. This will maintain the tornado threat for the next hour or so. Beyond this time frame, increasing storm interactions casts some uncertainty into the longevity of any one cell. Further the southeast across eastern NE into far northeast KS, cell development is noted along the dryline where richer boundary-layer moisture is supporting MLCAPE values in excess of 1500-3000 J/kg. Additionally, VWP observations from KOAX, supported by recent 19 UTC soundings from OAX and TOP, suggest low-level SRH is on the order of 100-150 m2/s2, which should support an increasing tornado threat over the next couple of hours as cells mature, but prior to gradual upscale growth this evening. An additional watch may be needed in the near-term for parts of northeast KS to address this concern. ..Moore.. 05/12/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EAX...FSD...OAX...TOP...GID...LBF... LAT...LON 41009818 41499940 41690014 41920067 42340072 42810024 42979928 42739761 42149664 41329612 40349557 39689548 39449625 39409667 40359731 41009818 NNNN