ZCZC SPCSWOMCD ALL ACUS11 KWNS 211915 SPC MCD 211915 MOZ000-ARZ000-OKZ000-KSZ000-212115- Mesoscale Discussion 0874 NWS Storm Prediction Center Norman OK 0215 PM CDT Tue May 21 2024 Areas affected...Eastern KS...Western MO...Northeast OK...Far Northwest AR Concerning...Severe potential...Watch likely Valid 211915Z - 212115Z Probability of Watch Issuance...80 percent SUMMARY...Severe thunderstorm development is anticipated this afternoon from eastern Kansas into western Missouri, northeast Oklahoma, and far northwest Arkansas. All severe hazards are possible and a watch will likely be needed soon. DISCUSSION...Visible satellite imagery shows increasingly agitated cumulus ahead of a surface trough extending arcing southeastward into northeast KS and then back southwestward from east-central KS through north-central OK. The airmass preceding this boundary is characterized by temperatures in the mid to upper 80s, dewpoints in the upper 60s/low 70s, and strong buoyancy. Recent mesoanalysis estimates MLCAPE around 2500 J/kg is currently in place, with the 18Z TOP sounding sampling 3100 J/kg. This same sounding revealed that much of the convective inhibition has been eroded, although the warm-layer between 800-700 mb could still result in updrafts struggling to mature. The general expectation is that additional heating should help diminish the effect of that warm layer even more, with both increasing large-scale ascent and convergence along the boundary providing the lift needed for convective initiation. This initiation will likely begin in the northeast KS/Kansas City vicinity before expanding southward/southwestward over time. Deep-layer shear is strong enough to support organized updrafts/supercells, with all severe hazards possible. Given the strong buoyancy, most prominent hazard appears to be large to very large hail. Strong downdrafts appear possible as well. Low-level flow is a bit weaker in this region that areas farther south, resulting in a modest weakness in the hodograph, which could act to inhibit tornadogenesis. However, given the likely organized character to the storms, there is still some tornado potential with any discrete storm. A watch will likely be needed soon to address these hazards. ..Mosier/Guyer.. 05/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF...EAX...TSA...TOP...ICT... LAT...LON 39999502 40479441 40339322 38629301 36579381 35999517 36259658 37979582 39999502 NNNN