Mesoscale Discussion 1215 NWS Storm Prediction Center Norman OK 0645 PM CDT Sat Jun 20 2026 Areas affected...eastern Nebraska and north-central into northeast Kansas Concerning...Severe potential...Watch possible Valid 202345Z - 210145Z Probability of Watch Issuance...40 percent SUMMARY...Thunderstorms continue this evening across eastern Nebraska. These storms will pose the potential for gusty strong-to-severe winds and hail. The area is being monitored for a possible watch. DISCUSSION...Clusters of elevated thunderstorms continue to develop this afternoon across portions of eastern Nebraska as southwesterly moist warm-air advection in the 850-700 millibar layer continues into the region. Strongly veering-with-height wind profiles have resulted in effective-layer shear around 50 knots across the region, which has yielded thunderstorm organization, with overall storm motion to the southeast given the northwesterly mid-to-upper-level flow. Thermodynamically, the continued convection across eastern Nebraska is reinforcing a northwest-to-southeast surface boundary, which is effectively serving as a instability gradient. To the southwest of this boundary, MUCAPE between 2500-3000 J/kg exists, with MUCAPE quickly dropping off to less than 500 J/kg to the northeast. Two main areas to monitor have emerged over the past hour. The first is across southeast Nebraska where an elevated supercell has produced hail around 1" per a local storm report from WFO Omaha. This storm should continue to move east-southeast toward the greater Kansas City Metro. A secondary area is to the northwest, where several thunderstorms have organized into an elevated linear MCS that has produced reports of 60-70 mph wind gusts. This MCS will continue to track southeast. The region will be monitored for signs that the severe potential is evolving from largely independent, isolated occurrences to a more organized, sustained threat. If this evolution occurs, a watch may be necessary. ..Marsh/Smith.. 06/20/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EAX...OAX...TOP...GID...LBF... LAT...LON 40899948 42039861 40089475 39299487 39329604 40899948 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
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