ZCZC SPCSWOMCD ALL ACUS11 KWNS 131906 SPC MCD 131906 MOZ000-IAZ000-KSZ000-NEZ000-132130- Mesoscale Discussion 0239 NWS Storm Prediction Center Norman OK 0206 PM CDT Fri Apr 13 2018 Areas affected...Eastern Kansas...Northwest Missouri...Far Southeast Nebraska...Southern Iowa Concerning...Severe potential...Watch likely Valid 131906Z - 132130Z Probability of Watch Issuance...80 percent SUMMARY...A severe threat is likely to develop across northeast Kansas, northwest Missouri and southern Iowa over the next couple of hours. Large hail and wind damage will be the initial threat but a tornado threat is expected to eventually develop. Weather watch issuance will likely be needed across the region this afternoon. DISCUSSION...The latest surface analysis shows a 991 mb low over far southeast Nebraska with a cold front extending south-southwestward from the low into northeast and central Kansas. A dryline begins near the front in eastern Kansas and extends southward into northern Oklahoma. Thunderstorms are developing along the dryline in southeast Kansas with other cells initiating to the north of the low in the Omaha area. This convection is expected to increase in coverage as the cap weakens over the next hour or so. The storms should reach northwest Missouri and southwest Iowa by mid afternoon. Ahead of the storms, a corridor of low-level moisture is analyzed from far southeast Kansas northward into far northwest Missouri where surface dewpoints are in the lower to mid 60s F. The RAP is showing MLCAPE values from eastern Kansas into far southwest Iowa in the 2000 to 2500 J/kg range. In addition, forecast soundings steadily increase deep-layer shear along the instability corridor through late this afternoon. 0-6 km shear should reach the 40 to 50 kt range which will be favorable for supercell development. The instability, shear and steep mid-level lapse rates will be support large hail formation with the stronger updrafts. Damaging wind gusts will also be likely as storm organize. As deep-layer shear and low-level shear increase later this afternoon, a tornado threat will also likely develop. ..Broyles/Hart.. 04/13/2018 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...DMX...EAX...OAX...TOP...ICT... LAT...LON 37869651 38009477 39089392 40369332 41209342 41469430 41549544 41159619 40559642 39759647 38359705 37869651 NNNN