Mesoscale Discussion 1347 NWS Storm Prediction Center Norman OK 0515 PM CDT Thu Jun 20 2024 Areas affected...Portions of northeast Colorado into the Nebraska Panhandle Concerning...Severe Thunderstorm Watch 439... Valid 202215Z - 202345Z The severe weather threat for Severe Thunderstorm Watch 439 continues. SUMMARY...While large hail and a tornado or two will remain possible, particularly within more favorable mesoscale corridors, the primary hazard over the next few hours will likely be severe gusts associated with a developing MCS in the Nebraska Panhandle. DISCUSSION...A supercell in eastern Wyoming, which was responsible for a few 4.5 in. hail reports, has grown upscale into a linear segment in the western Nebraska. This has occurred as the activity moved into a very well-mixed boundary layer. Given this trend, potential for severe gusts will likely increase with time. This complex recently produced a 61 kt gust at Scottsbluff, NE. Large hail will also remain possible, though very-large hail will be conditional on a supercell mode. Some tornado risk will also remain with the remnant supercell circulation/bookend vortex as well as with any storm favorably interacting with the warm front in northern Nebraska. As a cold pool circulation matures in the Nebraska Panhandle, an increasing low-level jet should promote storm maintenance into the evening farther east. Farther south into the Foothills, storms will likely remain more disorganized due to weaker shear. However, large hail and perhaps a weak tornado (due to ambient low-level vorticity stretched by updrafts) may still occur. ..Wendt.. 06/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...BOU...CYS... LAT...LON 40260515 41310442 41780406 42350381 42820258 42660202 41710215 40470323 40130420 40090491 40260515